Historic Pacific Northwest Heatwave of 2021

[Typhoon Tip]

On 6/29/2021 at 10:40 AM, donsutherland1 said:

I agree. The nonlinear impacts can be consequential, yet they are difficult to identify. So far, the extremes have been greater than what one might assume from a linear relationship between warming and related extremes. This early experience should encourage society to be cautious about letting things move toward a 2C or 3C warming.

If one recalls, the March 2012 heat produced some 5 sigma deviations. Now, part of the country has just witnessed what such extremes look like in the summer. 

We/you're presently discussing physical impacts .. but the conversation reminds me:

Special climate reports have elucidated a phenomenon globally:  heat has demonstrated a tendency to over-perform beyond leading indicators, seemingly "synergistically"  - it can be shown in the data, specific heat waves have very tall spikes the are disproportionately high, and very brief, in the y coordinate over the frame of reference which is much more modestly above normal.

I think there is some blurred metaphoric ( ..perhaps physical analogy if mathematically can be shown - ) to rogue wave phenomenon in a fluid mechanics.  The waves in present context deal with electromagnetism/ and thermodynamic waves, as opposed to fluid mechanics - but ...

All the environmental components that ultimately plays their forcing role in the emergence of the Pac NW heat, come into "constructive interference" - this "encourages" those variables that were undesignated in the physical system to then take on momentum in favor.  When this happens, the total entropy of motion and thermodynamics in a system is reduced, and the system's construction thus exceeds expectation.  In this case, heat.

 

 

 

[lookingnorth]

4 hours ago, TimB84 said:

But isn’t Chelan County in Washington? Even so, 119 would still be a state record.

I didn't even see that the second half of the list was for places in Washington.

[TimB]

5 minutes ago, lookingnorth said:

I didn't even see that the second half of the list was for places in Washington.

It was a long list of ridiculously hot temperatures, we’ll forgive you.

[donsutherland1]

1 hour ago, bdgwx said:

So the old Canadian record was 113F (45.0C) in 1937 and the new record is 121F (49.6C) in 2021. 

Let's say the recurrence interval on the 113F is 50 years and the mean annual Tmax is say 102F with a standard deviation of 5.4F for an annualized z-score of 2.0 (1-in-50 years). Using the mean of 102 +/- 5.4F (1-sigma) the annualized z-score on the 121F would be 3.5 (1-in-5,000 years).

Obviously that was just a back-of-the-envelope estimation without any hard data. I have no idea how far off that 102 +/- 5.4F figure is; could be a lot. If someone can supply the annual Canadian Tmax values we can compute the real mean and standard deviation and then just plug all of that into a z-score calculator and get the real recurrence interval for the 121F. My bet...the real recurrence interval from rigorous statistical analysis will be at least several hundred years and probably over a thousand and maybe even approaching the 5000 year figure I guesstimated above.

Here are the annual maximums at Lytton (RCS), BC:

2006 42.1
2007 40.8
2008 40.4
2009 40.6
2010 38.3
2011 35.5
2012 40.3
2013 40.5
2014 41.1
2015 40.2
2016 38.5
2017 40.1
2018 41.4
2019 37.7
2020 41.4
2021 49.6

[bdgwx]

32 minutes ago, donsutherland1 said:

Here are the annual maximums at Lytton (RCS), BC:

2006 42.1
2007 40.8
2008 40.4
2009 40.6
2010 38.3
2011 35.5
2012 40.3
2013 40.5
2014 41.1
2015 40.2
2016 38.5
2017 40.1
2018 41.4
2019 37.7
2020 41.4
2021 49.6

Perfect. Thanks.

Excluding 2021 the mean was 104F (40C) with a standard deviation of 3.0F (1.7C). The z-score for 121F (49.6C) is thus 5.6 implying a recurrence interval of 1-in-10,000,000 years.

Including 2021 the mean is 105F (40.5C) with a standard deviation of 5.1F (2.8C). The z-score for 121F (49.6C) is thus 3.1 implying a recurrence interval of  1-in-1200 years.

Clearly this was an astonishingly rare event in statistical terms.

 

[LibertyBell]

On 6/29/2021 at 9:28 AM, donsutherland1 said:

I don’t think so. I’m concerned that the will for concrete action is weakening in Washington. No matter how it is spun, the bipartisan infrastructure bill’s being decoupled with climate change-related legislation is a major step backward. While it has a few modest climate items, it is not a credible downpayment toward net zero emissions by 2030. The youth demonstrating outside the White House yesterday have legitimate reason for concern. Absent credible legislation, U.S. COP26 commitments will be hollow. Promises not backed by concrete substance are wishes.

I dont like some of these department picks either, Vilsack being one of them.  The older generation is holding on for dear life.
 

[LibertyBell]

1 hour ago, bdgwx said:

So the old Canadian record was 113F (45.0C) in 1937 and the new record is 121F (49.6C) in 2021. 

Let's say the recurrence interval on the 113F is 50 years and the mean annual Tmax is say 102F with a standard deviation of 5.4F for an annualized z-score of 2.0 (1-in-50 years). Using the mean of 102 +/- 5.4F (1-sigma) the annualized z-score on the 121F would be 3.5 (1-in-5,000 years).

Obviously that was just a back-of-the-envelope estimation without any hard data. I have no idea how far off that 102 +/- 5.4F figure is; could be a lot. If someone can supply the annual Canadian Tmax values we can compute the real mean and standard deviation and then just plug all of that into a z-score calculator and get the real recurrence interval for the 121F. My bet...the real recurrence interval from rigorous statistical analysis will be at least several hundred years and probably over a thousand and maybe even approaching the 5000 year figure I guesstimated above.

wtf....is that the furthest north a 50C (rounding up) or 120+ temp has ever occurred anywhere on the planet?

 

[LibertyBell]

18 hours ago, TimB84 said:

Pendleton and Hermiston, Oregon are both up to 117. This discussion about 117 vs. 119 could be moot soon.

odds are 50/50 that both OR and WA reach or exceed 120 F within the next decade

 

[LibertyBell]

11 hours ago, Roger Smith said:

Part three of the NYC "hot week" study analyzing the top averages on a year by year basis. As with the highs where I reported in more detail, consecutive values for 3-4 days (representing 9-10 days elapsed time) may be quite similar. This list ranks the years by top daily values only. Then it compares the sample of years to those identified as hottest daytime and warmest overnight. 

In the table below, entry "a" refers to the rank of the same year in average 7d maximum and minimum temps, and entry "b" refers to the day shift (if any) between the seven day intervals involved (for mean and max only). A positive number in "b" means that the mean temp max occurred that number of days later than the avg max, and a negative means that it occurred earlier. Zero means that it was the same seven day interval. Where either statistic was on more than one day, the best fit is used but an asterisk will be added. As an example of how to read the table, 1993 (avg 87.43) has the highest seven day mean and also the third highest ranked average maximum and tied 11th warmest minimum (a). The two intervals were concurrent (with reference to the first part of the study, that interval is identified as July 7-13). If b had been entered as "1" then the reference would be to 8-14 July for the mean temperature. If a year failed to make top 48 in mean max or mean min, that entry would read blank or --- . The first example of that is 1991 (t12) which did not register a top 48 7-day average min and the value of 73.57 was a degree lower than 48th ranked values. 

Two cases are noted (1980, 1999) where the highest average minimum was in a different heat wave than the highest average max. It probably happens more frequently in average and cooler than average summers.

Even when the mean max and the mean daily align, the mean minimum peak may be displaced. This is why 2010 came in with a slightly lower mean than 1980 even though its ranks were both slightly better. The relevant ranked mean minimum was displaced one day later. 

 

Rank ____ Avg ____ Year ____ a _______ b ________ Rank ___ Avg _____ Year ____ a ______ b

_01 _____ 87.43 ___ 1993 ___ 3, t11 ___ 0 _________ 26 ____ 84.43 ___ 1911 ___25, t29 __0

_02 _____ 87.36 ___ 1977 ___ 1, t20 ___ 0 _________ 27 ____ 84.14 ___ 1917 ___t31, t29__0

_03 _____ 87.14 ___ 1953 ___ 2, t16 ___ 0* ________t28 ____ 84.07 ___ 1885 __ t39, t16 __4

_04 _____ 87.07 ___ 1896 ___t13, 2 ___ 0 _________ t28 ____ 84.07 ___ 1898 __ -----, t13 __0 ^^

_05 _____ 86.86 ___ 2013 ___ 23, 1 ___ 1 __________t30 ____ 84.00 ___ 1892 __ t31, t29__ 1

_06 _____ 86.79 ___ 2011 ___ t7, 4 ___ 0* _________ t30 ____ 84.00 ___ 2016 __ ----, t11 __ 1^^

_07 _____ 86.64 ___ 1988 ___ t11, 3 __ 0 __________ 32 ____ 83.86 ___ 1949 __  t44, -----__ 0

_08 _____ 85.86 ___ 1944 ___ 5, t37___1 __________ t33____ 83.79 ___ 1876 __ t49, t25 __ 1

_09 _____ 85.71 ___ 1955 ___ 6, t29 __ 0 __________ t33 ____83.79 ___ 1961 __ t44, t29 __ 0

_10 _____ 85.57 ___ 2001 ___ t11, 24__0 __________t33 ____ 83.79 ___ 1984 __ t39, t42 __ 0

_11 _____ 85.50 ___ 1980 __ t20, t22^_ 0 __________t36 ____83.64 ___ 1982 __ t53, t29 __ 0

t12 _____ 85.43 ___ 1973 ___ t7, t37 __ 0 __________t36 ____83.64 ___ 2018 __ -----, t29 __ 0

t12 _____ 85.43 ___ 1981 ___24, t13 __ 0 __________ 38 ____ 83.57___ 1940 __ t26, ----- __ 0

t12 _____ 85.43 ___ 1991 ___ 4, ----- ___ 0 __________t39 ____ 83.50___ 1872 __ t31, ----- __ 0

_15 _____ 85.36 ___ 2010 __ t13, t16__ 0 __________ t39 ____83.50___ 2005 __ t44, t29 __ 1

_16 _____ 85.29 ___ 2002 __ t22, t20 __0 __________t41 ____ 83.43___ 1937 __ 28, ----- ___ 0

_17 _____ 85.21^___1999 __ ----- 6 ____ 0 __________t41 ____ 83.43 ___ 1972 __ -----, t27 ___--1  

_18 _____ 85.14 ___ 1948 __ t15, t29 _ 0 __________t43 ____ 83.36 ___ 1905 __ -----, t8 ____ --5

t19 _____ 84.93 ___ 1901 ___10, t46 __0 __________t43 ____ 83.36 ___ 1908 __ ------, 5 ____ 0

t19 _____ 84.93 ___ 1983 __ t15, t42__ 0 __________t43 ____ 83.36 ___ 1936 __ t20, ----- ___ 0 

t19 _____ 84.93 ___ 1995 __ t29, 15 __ 0 __________ 46 ____ 83.21 ___ 1943 ___ t29, ---- ___ 0

t22 _____ 84.79 ___ 1952 __ t31, t16 _ 0 __________t47 ____ 83.07 ___ 1925 ___ t15, ---- ___ 0

t22 _____ 84.79^___ 1966 __ t7, ----- __ 1 __________t47 ____ 83.07___ 2008 ____t37, ---- ___ 1

_24 _____ 84.71 ___ 2006 __ t49, 7 ___0 __________ 49 ____ 82.86 ___ 1979 ____----, t22 ___--4

_25 _____ 84.50 ___ 1933 __ t15, ---- __0 __________ 50 ____ 82.71 ___ 1906 ____ ----, t8 ____ 0

___________ (min for 1933 74.0, about 0.5 below 48th) ____^^ 1898 mean max 91.14, all peaks Aug 31 to Sept 6 1898

______________ (min for 1923 in 31st also 74.0) ______________^^ 2016 was similar, max 91.14, mean peak Aug 11-17 2016

_________________________________________________________________________

* Highest mean for 1953 is same as second of two tied intervals for high max (that ending Sept 3). The value for Sept 2 is marginally lower.

* Highest mean for 2011 also same as second of two tied intervals for high max (that ending July 27). 

^ For the 1980 entry, the mean min for the heat wave with the average shown (July) was slightly lower than a second heat wave with a lower average max. For the heat wave noted, the mean min was 76.14 which ranks t22nd, but for a second heat wave in August which had a mean of 85.00 (Aug 5-11), the average min was 77.00 (also Aug 5-11) and the peak average max 93.57 (Aug 3-9) so the displacement for this one was 2 days, the ranks of the mean max and mean min were t29, 10. In 2002, the earlier noted portion had a mean of 84.79, slightly lower than the peak heat wave, and the minimum of 75.14 was likewise about a degree lower than the peak heat wave recorded. 

^ For the 1999 entry, the highest mean occurred in a separate non-qualifying (for mean max) heat wave 22-23 days before tied peaks for mean max later in the summer. The non-qualifying mean max for the overall mean shown was 93.00. This one combined with the 6th highest average minimum of 77.00. After three weeks of less prolific heat, a second heat wave set the qualifying 95.00 peak (t15th warmest) on two consecutive days (for seven day averages) but with that heat wave the corresponding mean min was 74.71 which ranks t45 with otherwise untied 1870 (about t47 for separate heat waves). So 1999 set the 15th warmest mean max and 6th warmest mean min, although three weeks apart, and had two ranking heat waves for mean temperature if that were the criteria for counting. 

^ For the 1966 entry, the highest min was slightly lower than 48th. A later portion of the extended heat wave as noted had a slightly lower value of mean minimum attached also. The mean for the second interval was 83.57 which was 1.22 below the main peak ten days earlier. This is not considered to be a separate heat wave but an extended portion of the qualifying case.

(notes about secondary peaks, in 1955 the earlier July sub-peak had a mean of 85.29 (zero days displacement relative to mean max) -- this would rank as 23rd highest heat wave mean temp and would combine equivalent t10 mean daytime max with equivalent t37 mean min (almost equal to the later main entry heat wave),  in 1953 the July heat wave (listed as 2b for mean max) had a mean of 83.50 displaced one day later than the mean max peak, and a mean minimum of 73.43 which would rank outside the top 48 by about one degree, while in 1988 the earlier July sub-peak had a mean of 82.79 five days after the mean max peak showing the longevity of that heat wave). This one would rank t27 for heat wave mean max, and its mean minimum finished well outside the top 48. 

The heat waves of 1905 to 1908 and also 1979 generally levelled off near 88-90F and had warmer ranked overnight lows in the 75-77 range, for unusually small diurnal ranges. This may indicate frequent sea breeze modification, or cloudiness.

the years you mentioned had some of the hottest summers on record (note the 11 yr cycle)..... 1944, 55, 66, 77, 88, 99, 2010.....

2021 is part of that 11 yr cycle

some other ones with extremely hot summers were 1980, 83, 91, 93

 

[LibertyBell]

On 6/29/2021 at 10:46 AM, A-L-E-K said:

we aren't even trying

at this point, the worse it gets the better.  You wont see real action until the world is basically burning down

 

[donsutherland1]

1 hour ago, LibertyBell said:

wtf....is that the furthest north a 50C (rounding up) or 120+ temp has ever occurred anywhere on the planet?

 

Yes. This is the highest temperature ever recorded at or above 50N.

[Vice-Regent]

1 hour ago, LibertyBell said:

odds are 50/50 that both OR and WA reach or exceed 120 F within the next decade

 

Actually not necessarily as onshore flow could dominate more consistently much like the climate of California. We are just in a bad spot right now with cooler oceans and high atmospheric forcing.

[psv88]

2 hours ago, LibertyBell said:

odds are 50/50 that both OR and WA reach or exceed 120 F within the next decade

 

No. This was a once in a thousand year + event. My gut tells me Portland will not exceed this temp in our lifetimes.

[Roger Smith]

Another factor to consider is the lack of contrail cloud this year. In Canada especially we have not returned to pre-COVID levels of airline activity and southern BC has a lot of contrail cloud normally, being under the main jet route from Vancouver to central and eastern Canada. It has been quite noticeable that our skies have been very clear in the past year (when clear weather is available from the synoptics of course). In previous years we would have had 10-20 per cent sky cover from contrail debris in some of these hot, sunny episodes. 

One factor in this extreme heat is probably that the ground had warmed up considerably before the super heat arrived. We had a week near 35 C across the region in advance of this 42-48 C heat wave. The first two days normally would have been less extreme as the ground warmed up, but it already had done so. 

I am not so sure about thousand or million year return periods, this was a 599 dm high moving inland, it has happened before but not with quite this force of heating. Part of my doubt about return period is that we don't know how extreme this climate may have been in the past, for example, the Anasazi people had built a widespread agricultural civilization in the desert southwest in the 11th and 12th centuries and they suddenly vanished from the landscape around 1180 to 1200 A.D. -- why? Inter-tribal warfare is possibly the reason, but down there most cultural anthropologists seem to think the reason was extreme drought and heat forcing these people out of the region. Some of their ruined settlements show evidence of fires spreading rapidly.

This may unfortunately be something we could expect to see, warmed up by 2-3 deg of AGW perhaps. It has to be said that if the 1936 heat wave repeated this summer or any summer soon, we would hear a lot of comments such as "runaway global warming caused this" but unless there's some reason why 1936 should have been that hot, and 2021 should not, I can't see that as a proven theory, just a hypothesis. Anyone can make a hypothesis. 

[bluewave]

2 hours ago, Roger Smith said:

It has to be said that if the 1936 heat wave repeated this summer or any summer soon, we would hear a lot of comments such as "runaway global warming caused this" but unless there's some reason why 1936 should have been that hot, and 2021 should not, I can't see that as a proven theory, just a hypothesis. Anyone can make a hypothesis. 

 

The Dust Bowl was an early example of humans altering the Great Plains climate through land degradation. We had a big hand in the magnitude of the record heat. Now we are cooling the region through our farming practices.

https://www.nature.com/articles/s41467-020-16676-w

The severe drought of the 1930s Dust Bowl decade coincided with record-breaking summer heatwaves that contributed to the socio-economic and ecological disaster over North America’s Great Plains. It remains unresolved to what extent these exceptional heatwaves, hotter than in historically forced coupled climate model simulations, were forced by sea surface temperatures (SSTs) and exacerbated through human-induced deterioration of land cover. Here we show, using an atmospheric-only model, that anomalously warm North Atlantic SSTs enhance heatwave activity through an association with drier spring conditions resulting from weaker moisture transport. Model devegetation simulations, that represent the wide-spread exposure of bare soil in the 1930s, suggest human activity fueled stronger and more frequent heatwaves through greater evaporative drying in the warmer months. This study highlights the potential for the amplification of naturally occurring extreme events like droughts by vegetation feedbacks to create more extreme heatwaves in a warmer world.

 

https://www.sciencemag.org/news/2018/02/america-s-corn-belt-making-its-own-weather

The Great Plains of the central United States—the Corn Belt—is one of the most fertile regions on Earth, producing more than 10 billion bushels of corn each year. It’s also home to some mysterious weather: Whereas the rest of the world has warmed, the region’s summer temperatures have dropped as much as a full degree Celsius, and rainfall has increased up to 35%, the largest spike anywhere in the world. The culprit, according to a new study, isn’t greenhouse gas emissions or sea surface temperature—it’s the corn itself.

This is the first time anyone has examined regional climate change in the central United States by directly comparing the influence of greenhouse gas emissions to agriculture, says Nathan Mueller, an earth systems scientist at the University of California (UC), Irvine, who was not involved with this study. It’s important to understand how agricultural activity can have “surprisingly strong” impacts on climate change, he says.

[MN Transplant]

The Kamloops, BC temp from today (115) would have set the all-time Canadian record if Lytton (and others) hadn’t gone thermonuclear the past few days.

And Ft. Smith in the Northwest Territories has apparently set that province’s all-time record at 103.

[donsutherland1]

Weather summary
for British Columbia
issued by Environment Canada
at 6:32 p.m. PDT Wednesday 30 June 2021.

Discussion.

The following areas will have set a daily maximum temperature record 
on June 30, 2021: 

Blue River Area (Blue River CS) 
Preliminary new record of 40.3 
Old record of 35.0 set in 2008 
Records in this area have been kept since 1946 

Cache Creek Area (Ashcroft) 
Preliminary new record of 47.0 
Old record of 36.3 set in 2017 
Records in this area have been kept since 1944 

Clearwater Area (Clearwater Auto) 
Preliminary new record of 44.9 
Old record of 36.7 set in 1924 
Records in this area have been kept since 1913 

Clinton Area (Clinton RCS) 
Preliminary new record of 41.2 
Old record of 31.7 set in 2008 
Records in this area have been kept since 1974 

Cranbrook Area (Cranbrook A) 
Preliminary new record of 39.4 
Old record of 34.8 set in 2008 
Records in this area have been kept since 1901 

Creston Area (Creston Campbell Scientific) 
Preliminary new record of 41.3 
Old record of 35.0 set in 1924 
Records in this area have been kept since 1912 

Dawson Creek Area (Dawson Creek A) 
Preliminary new record of 34.9 
Old record of 27.4 set in 2008 
Records in this area have been kept since 1926 

Fort Nelson Area (Fort Nelson) 
Preliminary new record of 31.4 
Old record of 30.8 set in 1982 
Records in this area have been kept since 1937 

Fort St. John Area (Fort St. John A) 
Preliminary new record of 34.6 
Old record of 27.2 set in 1942 
Records in this area have been kept since 1910 

Golden Area (Golden Airport) 
Preliminary new record of 40.7 
Old record of 33.9 set in 1924 
Records in this area have been kept since 1902 

Kamloops Area (Kamloops A) 
Preliminary new record of 46.6 
Old record of 38.5 set in 2008 
Records in this area have been kept since 1890 

Kelowna Area (Kelowna UBCO) 
Preliminary new record of 44.4 
Old record of 37.3 set in 2008 
Records in this area have been kept since 1899 

Lillooet Area (Lillooet) 
Preliminary new record of 42.2 
Old record of 38.5 set in 1987 
Records in this area have been kept since 1917 

Mackenzie Area (Mackenzie Airport Auto) 
Preliminary new record of 35.2 
Old record of 29.7 set in 1982 
Records in this area have been kept since 1971 

Merritt Area (Merritt) 
Preliminary new record of 43.8 
Old record of 36.5 set in 2008 
Records in this area have been kept since 1918 

Nakusp Area (Nakusp CS) 
Preliminary new record of 40.4 
Old record of 33.0 set in 2006 
Records in this area have been kept since 1966 

Osoyoos Area (Osoyoos CS) 
Preliminary new record of 43.0 
Old record of 38.5 set in 2008 
Records in this area have been kept since 1954 

Penticton Area (Penticton A) 
Preliminary new record of 44.2 
Old record of 37.7 set in 1987 
Records in this area have been kept since 1907 

Prince George Area (Prince George Airport Auto) 
Preliminary new record of 34.3 
Old record of 33.9 set in 1942 
Records in this area have been kept since 1912 

Princeton Area (Princeton CS) 
Preliminary new record of 43.1 
Old record of 36.1 set in 1942 
Records in this area have been kept since 1893 

Puntzi Mountain Area (Puntzi Mountain (AUT)) 
Preliminary new record of 36.9 
Old record of 31.8 set in 2008 
Records in this area have been kept since 1959 

Quesnel Area (Quesnel Airport Auto) 
Preliminary new record of 35.4 
Old record of 35.0 set in 1942 
Records in this area have been kept since 1893 

Revelstoke Area (Revelstoke Airport Auto) 
Preliminary new record of 38.1 
Old record of 35.0 set in 1924 
Records in this area have been kept since 1898 

Salmon Arm Area (Salmon Arm CS) 
Preliminary new record of 42.9 
Old record of 38.3 set in 1924 
Records in this area have been kept since 1893 

Sparwood Area (Sparwood CS) 
Preliminary new record of 35.4 
Old record of 33.8 set in 2008 
Records in this area have been kept since 1969 

Summerland Area (Summerland CS) 
Preliminary new record of 44.7 
Old record of 37.0 set in 1987 
Records in this area have been kept since 1907 

Tatlayoko Lake Area (Tatlayoko Lake RCS) 
Preliminary new record of 34.7 
Old record of 31.3 set in 2008 
Records in this area have been kept since 1930 

Trail Area (Warfield RCS) 
Preliminary new record of 44.8 
Old record of 36.1 set in 1938 
Records in this area have been kept since 1928 

Vernon Area (Vernon Auto) 
Preliminary new record of 43.9 
Old record of 37.3 set in 2008 
Records in this area have been kept since 1900 

Williams Lake Area (Williams Lake A) 
Preliminary new record of 37.1 
Old record of 30.8 set in 1987 
Records in this area have been kept since 1960 

Yoho (National Park) Area (Yoho Park) 
Preliminary new record of 37.9 
Old record of 31.1 set in 1940 
Records in this area have been kept since 1923 

Note: the temperature records reported here have been derived from a 
selection of historical stations in each geographic area that were 
active during the period of record.

Please note that this summary may contain preliminary or unofficial 
information and does not constitute a complete or final report.

End/PSPC

[Roger Smith]

This is no doubt the early stages but forest fires are growing in extent at a brisk rate, mostly in the Lytton and Kamloops areas so far. Human caused fires are more prevalent than lightning caused so far. One of these fires has moved into outskirts of Lytton and the town is under an evacuation order (it's a town of about 1,500 people). I never went out after the morning coffee run, but from the reports this is the hottest day here with the nearby station reporting 44 C around 4-5 pm. Going out now to catch the sunset and the inevitable drop below 35 C which is probably going to feel good. Our forecast as you probably know is for just a very slight temperature drop combined with an increasing risk of thunderstorms which in our case will blow in from the hills over northeast WA. It is not tinder dry around here despite a rather dry two month period, the winter was relatively moist and the ground moisture in the forests around here will last a few more weeks but eventually the fire hazard here will rise into the extreme category also. 

 

[donsutherland1]

22 minutes ago, Roger Smith said:

This is no doubt the early stages but forest fires are growing in extent at a brisk rate, mostly in the Lytton and Kamloops areas so far. Human caused fires are more prevalent than lightning caused so far. One of these fires has moved into outskirts of Lytton and the town is under an evacuation order (it's a town of about 1,500 people). I never went out after the morning coffee run, but from the reports this is the hottest day here with the nearby station reporting 44 C around 4-5 pm. Going out now to catch the sunset and the inevitable drop below 35 C which is probably going to feel good. Our forecast as you probably know is for just a very slight temperature drop combined with an increasing risk of thunderstorms which in our case will blow in from the hills over northeast WA. It is not tinder dry around here despite a rather dry two month period, the winter was relatively moist and the ground moisture in the forests around here will last a few more weeks but eventually the fire hazard here will rise into the extreme category also. 

 

I read that all of Lytton was ordered evacuated. The heat has inflicted a terrible toll on both sides of the border. Fires are now wreaking havoc at various locations.

[sojitodd]

I just saw some video from people evacuating Lytton and much of it appears to have been on fire-buildings could be seen burning. Widespread destruction reported with many structures burned up. Many people had to evacuate very quickly even having to leave pets behind. That town has literally been through hell- suffering Death Valley like temps and then much of it being engulfed by fire. Literal hell. 

https://www.cbc.ca/news/canada/british-columbia/bc-wildfires-june-30-2021-1.6085919

 

[LibertyBell]

12 hours ago, psv88 said:

No. This was a once in a thousand year + event. My gut tells me Portland will not exceed this temp in our lifetimes.

I'm wondering about this because of the recent bout of extreme heat we've seen that surpasses all previous records, especially at high latitudes.  Remember that Siberia had 6 months of extreme heat last year that was about +20F  above normal for an entire half year!  Thats mind boggling.

 

[LibertyBell]

1 hour ago, sojitodd said:

I just saw some video from people evacuating Lytton and much of it appears to have been on fire-buildings could be seen burning. Widespread destruction reported with many structures burned up. Many people had to evacuate very quickly even having to leave pets behind. That town has literally been through hell- suffering Death Valley like temps and then much of it being engulfed by fire. Literal hell. 

https://www.cbc.ca/news/canada/british-columbia/bc-wildfires-june-30-2021-1.6085919

 

How can that kind of extreme heat get so far north?

 

[LibertyBell]

1 hour ago, sojitodd said:

I just saw some video from people evacuating Lytton and much of it appears to have been on fire-buildings could be seen burning. Widespread destruction reported with many structures burned up. Many people had to evacuate very quickly even having to leave pets behind. That town has literally been through hell- suffering Death Valley like temps and then much of it being engulfed by fire. Literal hell. 

https://www.cbc.ca/news/canada/british-columbia/bc-wildfires-june-30-2021-1.6085919

 

Is it hot enough to actually get spontaneous combustion out there (hot enough for a fire to start without an outside trigger)?

 

[donsutherland1]

Weather summary
for Alberta
issued by Environment Canada
at 4:03 a.m. MDT Thursday 1 July 2021.

Discussion.

The following areas set a daily maximum temperature record on June 
30, 2021: 

Athabasca Area 
New record of 36.8 
Old record of 31.1 set in 1924 
Records in this area have been kept since 1900 

Banff Area 
New record of 37.4 
Old record of 31.2 set in 2008 
Records in this area have been kept since 1887 

Barrhead Area 
New record of 37.7 
Old record of 32.2 set in 1924 
Records in this area have been kept since 1912 

Beaverlodge Area 
New record of 37.1 
Old record of 31.7 set in 1924 
Records in this area have been kept since 1912 

Bow Island Area 
New record of 35.8 
Old record of 33.9 set in 2008 
Records in this area have been kept since 1961 

Bow Valley (Provincial Park) Area 
New record of 38.2 
Old record of 31.0 set in 2008 
Records in this area have been kept since 1928 

Breton Area 
New record of 35.6 
Old record of 30.4 set in 2003 
Records in this area have been kept since 1939 

Brooks Area 
New record of 37.0 
Old record of 35.6 set in 1944 
Records in this area have been kept since 1912 

Calgary Area 
New record of 35.9 
Old record of 33.3 set in 1892 
Records in this area have been kept since 1881 

Camrose Area 
New record of 35.2 
Old record of 31.9 set in 2003 
Records in this area have been kept since 1921 

Cardston Area 
New record of 34.4 
Old record of 32.2 set in 2008 
Records in this area have been kept since 1918 

Claresholm Area 
New record of 35.4 
Old record of 33.6 set in 2008 
Records in this area have been kept since 1951 

Cold Lake Area 
New record of 35.9 
Old record of 30.2 set in 2008 
Records in this area have been kept since 1952 

Coronation Area 
New record of 37.0 
Old record of 36.7 set in 1937 
Records in this area have been kept since 1912 

Edmonton Area 
New record of 37.0 
Old record of 31.7 set in 1896 
Records in this area have been kept since 1880 

Edmonton (int'l Aprt) Area 
New record of 33.7 
Old record of 29.7 set in 2003 
Records in this area have been kept since 1959 

Edson Area 
New record of 38.8 
Old record of 35.0 set in 1924 
Records in this area have been kept since 1916 

Elk Island (National Park) Area 
New record of 34.6 
Old record of 30.0 set in 2008 
Records in this area have been kept since 1966 

Fort Chipewyan Area 
New record of 39.3 
Old record of 31.6 set in 1979 
Records in this area have been kept since 1883 

Fort Mcmurray Area 
New record of 40.1 
Old record of 34.4 set in 1916 
Records in this area have been kept since 1908 

Grande Prairie Area 
New record of 38.5 
Old record of 28.9 set in 2008 
Records in this area have been kept since 1922 

Hendrickson Creek Area 
New record of 38.3 
Old record of 28.7 set in 2008 
Records in this area have been kept since 1995 

High Level Area 
New record of 33.4 
Old record of 30.7 set in 2013 
Records in this area have been kept since 1962 

High River Area 
New record of 35.4 
Old record of 32.0 set in 2008 
Records in this area have been kept since 1913 

Highvale Area 
New record of 36.9 
Old record of 29.5 set in 2008 
Records in this area have been kept since 1977 

Jasper Area 
New record of 41.2 
Old record of 33.6 set in 2008 
Records in this area have been kept since 1916 

Lethbridge Area 
New record of 36.3 
Old record of 33.9 set in 2008 
Records in this area have been kept since 1902 

Lloydminster Area 
New record of 32.9 
Old record of 32.2 set in 1944 
Records in this area have been kept since 1904 

Medicine Hat Area 
New record of 38.1 
Old record of 36.7 set in 1885 
Records in this area have been kept since 1883 

Lac La Biche Area 
New record of 35.6 
Old record of 28.9 set in 2008 
Records in this area have been kept since 1944 

Lacombe Area 
New record of 34.9 
Old record of 31.7 set in 1924 
Records in this area have been kept since 1907 

Mildred Lake Area 
New record of 40.5 
Old record of 30.5 set in 1978 
Records in this area have been kept since 1965 

Milk River Area 
New record of 35.4 
Old record of 32.7 set in 2008 
Records in this area have been kept since 1994 

Nordegg Area 
New record of 37.2 
Old record of 28.3 set in 1924 
Records in this area have been kept since 1915 

Peace River Area 
New record of 38.7 
Old record of 36.1 set in 1924 
Records in this area have been kept since 1907 

Pincher Creek Area 
New record of 33.3 
Old record of 33.1 set in 2008 
Records in this area have been kept since 1893 

Red Deer Area 
New record of 34.8 
Old record of 30.6 set in 1944 
Records in this area have been kept since 1904 

Red Earth Creek Area 
New record of 40.1 
Old record of 30.0 set in 2013 
Records in this area have been kept since 1994 

Rocky Mountain House Area 
New record of 35.4 
Old record of 29.8 set in 2003 
Records in this area have been kept since 1915 

Slave Lake Area 
New record of 38.3 
Old record of 27.7 set in 1979 
Records in this area have been kept since 1922 

Stavely Area 
New record of 31.5 
Old record of 31.0 set in 1990 
Records in this area have been kept since 1914 

Stettler Area 
New record of 36.4 
Old record of 33.3 set in 1944 
Records in this area have been kept since 1918 

Stony Plain Area 
New record of 35.7 
Old record of 29.6 set in 2008 
Records in this area have been kept since 1966 

Strathmore Area 
New record of 34.9 
Old record of 31.7 set in 1939 
Records in this area have been kept since 1912 

Sundre Area 
New record of 35.2 
Old record of 30.7 set in 2003 
Records in this area have been kept since 1993 

Taber Area 
New record of 36.5 
Old record of 34.6 set in 2008 
Records in this area have been kept since 1947 

Three Hills Area 
New record of 34.6 
Old record of 34.4 set in 1944 
Records in this area have been kept since 1921 

Vegreville Area 
New record of 35.4 
Old record of 32.2 set in 1944 
Records in this area have been kept since 1918 

Wainwright Area 
New record of 36.3 
Old record of 34.0 set in 2003 
Records in this area have been kept since 1966 

Note: the temperature records reported here have been derived from a 
selection of historical stations in each geographic area that were 
active during the period of record.

Please note that this summary may contain preliminary or unofficial 
information and does not constitute a complete or final report.

End/PASPC

[donsutherland1]

Weather summary
for British Columbia
issued by Environment Canada
at 12:13 a.m. PDT Thursday 1 July 2021.

Discussion.

The historic heat wave continues to shatter records across the 
province. 

The following areas set a daily maximum temperature record on June 
30, 2021: 

Blue River Area (Blue River CS) 
New record of 40.3 
Old record of 35.0 set in 2008 
Records in this area have been kept since 1946 

Cache Creek Area (Ashcroft) 
New record of 47.0 
Old record of 36.3 set in 2017 
Records in this area have been kept since 1944 

Clearwater Area (Clearwater Auto) 
New record of 44.9 
Old record of 36.7 set in 1924 
Records in this area have been kept since 1913 

Clinton Area (Clinton RCS) 
New record of 41.2 
Old record of 31.7 set in 2008 
Records in this area have been kept since 1974 

Cranbrook Area (Cranbrook A) 
New record of 39.4 
Old record of 34.8 set in 2008 
Records in this area have been kept since 1901 

Creston Area (Creston Campbell Scientific) 
New record of 41.3 
Old record of 35.0 set in 1924 
Records in this area have been kept since 1912 

Dawson Creek Area (Dawson Creek A) 
New record of 34.9 
Old record of 27.4 set in 2008 
Records in this area have been kept since 1926 

Fort Nelson Area (Fort Nelson) 
New record of 31.4 
Old record of 30.8 set in 1982 
Records in this area have been kept since 1937 

Fort St. John Area (Fort St. John A) 
New record of 35.1 
Old record of 27.2 set in 1942 
Records in this area have been kept since 1910 

Golden Area (Golden Airport) 
New record of 40.7 
Old record of 33.9 set in 1924 
Records in this area have been kept since 1902 

Kamloops Area (Kamloops A) 
New record of 46.6 
Old record of 38.5 set in 2008 
Records in this area have been kept since 1890 

Kelowna Area (Kelowna UBCO) 
New record of 44.4 
Old record of 37.3 set in 2008 
Records in this area have been kept since 1899 

Lillooet Area (Lillooet) 
New record of 42.2 
Old record of 38.5 set in 1987 
Records in this area have been kept since 1917 

Mackenzie Area (Mackenzie Airport Auto) 
New record of 35.2 
Old record of 29.7 set in 1982 
Records in this area have been kept since 1971 

Merritt Area (Merritt) 
New record of 43.8 
Old record of 36.5 set in 2008 
Records in this area have been kept since 1918 

Nakusp Area (Nakusp CS) 
New record of 41.0 
Old record of 33.0 set in 2006 
Records in this area have been kept since 1966 

Nelson Area (Nelson CS) 
New record of 40.7 
Old record of 35.6 set in 1915 
Records in this area have been kept since 1904 

Osoyoos Area (Osoyoos CS) 
New record of 43.0 
Old record of 38.5 set in 2008 
Records in this area have been kept since 1954 

Penticton Area (Penticton A) 
New record of 44.2 
Old record of 37.7 set in 1987 
Records in this area have been kept since 1907 

Prince George Area (Prince George Airport Auto) 
New record of 34.3 
Old record of 33.9 set in 1942 
Records in this area have been kept since 1912 

Princeton Area (Princeton CS) 
New record of 43.1 
Old record of 36.1 set in 1942 
Records in this area have been kept since 1893 

Puntzi Mountain Area (Puntzi Mountain (AUT)) 
New record of 36.9 
Old record of 31.8 set in 2008 
Records in this area have been kept since 1959 

Quesnel Area (Quesnel Airport Auto) 
New record of 35.4 
Old record of 35.0 set in 1942 
Records in this area have been kept since 1893 

Revelstoke Area (Revelstoke Airport Auto) 
New record of 38.1 
Old record of 35.0 set in 1924 
Records in this area have been kept since 1898 

Salmon Arm Area (Salmon Arm CS) 
New record of 42.9 
Old record of 38.3 set in 1924 
Records in this area have been kept since 1893 

Sparwood Area (Sparwood CS) 
New record of 35.4 
Old record of 33.8 set in 2008 
Records in this area have been kept since 1969 

Summerland Area (Summerland CS) 
New record of 44.7 
Old record of 37.0 set in 1987 
Records in this area have been kept since 1907 

Tatlayoko Lake Area (Tatlayoko Lake RCS) 
New record of 34.7 
Old record of 31.3 set in 2008 
Records in this area have been kept since 1930 

Trail Area (Warfield RCS) 
New record of 44.8 
Old record of 36.1 set in 1938 
Records in this area have been kept since 1928 

Vernon Area (Vernon Auto) 
New record of 43.9 
Old record of 37.3 set in 2008 
Records in this area have been kept since 1900 

Williams Lake Area (Williams Lake A) 
New record of 37.1 
Old record of 30.8 set in 1987 
Records in this area have been kept since 1960 

Yoho (National Park) Area (Yoho Park) 
New record of 37.9 
Old record of 31.1 set in 1940 
Records in this area have been kept since 1923 

Note: the temperature records reported here have been derived from a 
selection of historical stations in each geographic area that were 
active during the period of record.

Please note that this summary may contain preliminary or unofficial 
information and does not constitute a complete or final report.

End/PSPC

[donsutherland1]

Unprecedented North American Heatwave Scorches the Pacific Northwest

Words cannot describe this historic event.--Environment Canada, British Columbia forecast office

During late June 2021, extreme heat of unprecedented and seemingly unimaginable proportions singed the Pacific Northwest. In many parts of British Columbia, Oregon, and Washington, temperatures rose to the highest levels on record, sometimes by enormous margins. Even coastal locations found no relief from the sun's furnace-like heat. This extraordinary weather event was very likely the most severe outbreak of heat in North America since weather records were compiled.

The event was triggered by a quasi-resonant amplification of a Rossby wave (Mann et al., 2017) that led to the formation of a monster heat dome. In response, a super-intense heat event developed.

Table 1: 500 mb Geopotential Height Anomalies and Surface Temperature Anomalies (June 26-28, 2021)

This heatwave easily qualified as an Extreme Heat Event (EHE) in both Portland and Seattle. It is also the first common EHE for Portland and Seattle during June. At least 3 days saw the maximum , temperature exceed the 97.5th percentile (Portland: 98° or above; Seattle: 91° or above), and all high temperatures exceeded the 81st percentile (Portland: 87° or above; Seattle: 82° or above) in June-August high temperatures for the 1971-2000 base period (Clarke, et al.,2014). A disproportionate share of each city's EHEs has occurred 2000 or later. During 2018, Seattle had its first year with two such events.

Table 2: Portland’s and Seattle’s High Temperatures and Standardized Anomalies during the Peak of the June 2021 Heatwave

Table 3: Portland’s Average Summer Temperatures (30-Year Moving Average)

Table 4: Seattle’s Average Summer Temperatures (30-Year Moving Average)

Human-induced climate change has increased the frequency, magnitude, and duration of extreme heat events in the United States and worldwide. Climate change has increased the frequency, magnitude, and duration of extreme heat events in the United States and worldwide.

The rise in temperatures is increasing the statistical frequency and actual occurrences of notable heat (90° and 100° days in Portland and 90° days in Seattle). Seattle's 108° peak temperature was a 4.36 sigma departure from the 1951-80 summer average maximum temperature but a 4.16 sigma departure from the 1991-20 summer average maximum temperature. That means such an event, while rare, was now nearly 2.5 times as likely as it was during the earlier period. For Portland, the 116° peak temperature was a 4.37 sigma departure from the 1951-80 summer average maximum temperature, but a 4.05 sigma departure from the 1991-20 summer average maximum temperature. That means such an event, while rare, was now 4 times as likely as it was during the 1951-80 period.

Table 5: Statistical Probability of Select High Temperature Thresholds for June 26-28

Table 6: Actual Frequency of Select High Temperature Thresholds for June 26-28

Table 7: Annual Number of 90° Days

Table 8: Portland’s Record High Maximum Temperatures

Table 9: Portland’s Record High Minimum Temperatures

Table 10: Seattle’s Record High Maximum Temperatures

Table 11: Seattle’s Record High Minimum Temperatures

Table 12: Portland’s Extreme Heat Events:

Table 13: Seattle’s Extreme Heat Events:

Select Additional Heatwave Records:

Portland:

Highest maximum temperature: 116°, June 28, 2021 (old record prior to heatwave: 107°, July 30, 1965; August 8, 1981; and, August 10, 1981)

Highest mean temperature: 94.5°, June 28, 2021 (old record prior to heatwave: 90.0°, July 28, 2009

Highest minimum temperature: 75°, June 28, 2021 (old record prior to heatwave: 74°, July 17, 1941 and July 28, 2009

Highest 2-day average maximum temperature: 114.0°, June 27-28, 2021 (old record prior to heatwave: 106.0°, August 8-9, 1981; August 9-10, 1981; and, July 28-29, 2009)

Highest 2-day average minimum temperature: 74.0°, June 27-28, 2021 (old record prior to heatwave: 72.5°, July 28-29, 2009)

Highest 2-day average mean temperature: 94.0°, June 27-28, 2021 (old record prior to heatwave: 89.2°, July 28-29, 2009)

Highest 3-day average maximum temperature: 112.0°, June 26-28, 2021 (old record prior to heatwave: 106.3°, August 8-10, 1981)

Highest 3-day average minimum temperature: 72.7°, June 26-28, 2021 (old record prior to heatwave: 71.0°, July 27-29, 2009)

Highest 3-day average mean temperature: 92.3°, June 26-28, 2021 (old record prior to heatwave: 88.0°, July 27-29, 2009)

Highest 4-day average maximum temperature: 107.8°, June 25-28, 2021 (old record prior to heatwave: 105.5°, August 7-10, 1981)

Highest 4-day average minimum temperature: 70.8°, June 25-28, 2021 (old record prior to heatwave: 70.0°, July 27-30, 2009)

Highest 4-day average mean temperature: 89.3°, June 25-28, 2021 (old record prior to heatwave: 86.4°, July 27-30, 2009)

Highest 5-day average maximum temperature: 104.8°, June 25-29, 2021 (old record prior to heatwave: 104.2°, August 6-10, 1981)

Highest 5-day average minimum temperature: 69.2°, June 25-29, 2021 (old record prior to heatwave: 68.4°, July 27-31, 2009)

Highest 5-day average mean temperature: 87.0°, June 25-29, 2021 (old record prior to heatwave: 84.7°, July 27-31, 2009)

Most consecutive days 105° or above: 3, June 26-28, 2021 (tied record set during August 8-10, 1981)

Most consecutive days 110° or above: 3, June 26-28, 2021 (no prior record)

Most consecutive low temperatures 70° or above: 3, June 26-28, 2021 (old record: 2, July 16-17, 1941; July 27-28, 1998; and, July 28-29, 2009)

Seattle:

Highest maximum temperature: 108°, June 28, 2021 (old record prior to heatwave: 103°, July 29, 2009)

Highest minimum temperature: 73°, June 27, 2021 (old record prior to heatwave: 71°, July 29, 2009

Highest mean temperature: 88.5°, June 27, 2021 (old record prior to heatwave: 87.0°, July 29, 2009

Highest 2-day average maximum temperature: 106.0°, June 27-28, 2021 (old record prior to heatwave: 100.0°, July 28-29, 2009)

Highest 2-day average minimum temperature: 71.0°, June 26-27, 2021 (old record prior to heatwave: 70.0°, July 28-29, 2009)

Highest 2-day average mean temperature: 87.8°, June 27-28, 2021 (old record prior to heatwave: 85.0°, July 28-29, 2009)

Highest 3-day average maximum temperature: 104.7°, June 26-28, 2021 (old record prior to heatwave: 98.7°, July 28-30, 2009)

Highest 3-day average minimum temperature: 69.3°, June 26-28, 2021 (old record prior to heatwave: 68.3°, July 27-29, 2009)

Highest 3-day average mean temperature: 87.0°, June 26-28, 2021 (old record prior to heatwave: 83.2°, July 27-29, 2009)

Highest 4-day average maximum temperature: 100.2°, June 25-28, 2021 (old record prior to heatwave: 97.5°, July 27-30, 2009)

Highest 4-day average minimum temperature: 68.0°, June 25-28, 2021 (old record prior to heatwave: 66.8°, July 27-30, 2009)

Highest 4-day average mean temperature: 84.1°, June 25-28, 2021 (old record prior to heatwave: 82.1°, July 26-29, 2009)

Highest 5-day average maximum temperature: 97.2°, June 25-29, 2021 (old record prior to heatwave: 95.8°, July 26-30, 2009)

Highest 5-day average minimum temperature: 66.8°, June 25-29, 2021 (old record prior to heatwave: 66.0°, August 7-11, 1981)

Highest 5-day average mean temperature: 82.0°, June 25-29, 2021 (old record prior to heatwave: 80.7°, July 26-30, 2009)

Most consecutive high temperatures of 95° or above: 3, June 26-28, 2021 (tied record set during August 10-12, 1977 and tied on July 21-23, 2006 and July 28-30, 2009)

Most consecutive days 100° or above: 3, June 26-28, 2021 (old record: 1, July 20, 1994 and July 29, 2009

Most Extreme Records

Hoquiam, WA: 103° (old all-time record prior to heatwave: August 10, 1981 and August 19, 2016)

During the 1991-2020 climate period, Hoquiam's average summer (June-August) high temperature was 66.6° with a standard deviation of 5.882°. The 103° temperature marked a 6.196 sigma departure from the normal summer high temperature.

Quillayute, WA: 110° (old all-time record prior to heatwave: 99°, August 9, 1981)

During the 1991-2020 climate period, Quillayute's average summer (June-August) high temperature was 66.9° with a standard deviation of 6.968°. The 110° temperature marked a 6.183 sigma departure from the normal summer high temperature.

Select Record High Temperatures:

June 25, 2021:
Bellingham, WA: 86° (old record: 84°, 2017)
Ephrata, WA: 100° (tied record set in 1992)
Fort Nelson, BC: 90°/32.4°C (old record: 89°/31.7°C, 1955)
Lillooet, BC: 101°/38.6°C (old record: 99°/37.0°C, 2017)
Lytton, BC: 103°/39.2°C (old record: 101°/38.2°C, 2006)
Victoria, BC: 93°/34.1°C (old record: 86°/30.2°C, 2006) ***New June Record***

June 26, 2021:
Aurora, OR: 106° (old record: 101°, 2006) ***New June Record***
Bellingham, WA: 95° (old record: 83°, 2015) ***New June Record***
Dallesport, WA: 110° (old record: 103°, 2017) ***Tied June Record***
Ephrata, WA: 103° (old record: 102°, 2006)
Eugene, OR: 103° (old record: 99°, 2015) ***New June Record***
Hillsboro, OR: 106° (old record: 102°, 2006) ***New June Record***
Hermiston, OR: 108° (old record: 106°, 1925)
Hoquiam, WA: 87° (old record: 84°, 2000 and 2006)
Kamloops, BC: 105°/40.7°C (old record: 101°/38.4°C, 2006) ***New June Record***
Lillooet, BC: 110°/43.1°C (old record: 98°/36.6°C, 2002) ***New All-Time Record***
Lytton, BC: 111°/43.8°C (old record: 104°/39.9°C, 2006) ***New All-Time Record; New Canadian June Record***
McMinnville: 104° (old record: 103°, 2006)
Olympia: 102° (old record: 93°, 2006) ***New June Record; 1st 100° Temperature in June***
Omak, WA: 104° (old record: 102°, 1926 and 2015)
Pasco, WA: 110° (old record: 105°, 1925 and 2015)
Pendleton, OR: 104° (tied record set in 1925 and tied in 2015)
Portland: 108° (old record: 102°, 2006) ***New All-Time Record***
Redding, CA: 114° (old record: 113°, 2006)
Redmond, OR: 101° (tied record set in 1968 and tied in 2015)
Roseburg, OR: 105° (old record: 102°, 2006) ***New June Record***
Salem, OR: 105° (old record: 103°, 2006) ***Tied June Record***
Seattle: 102° (old record: 90°, 2006) ***New June Record***
Troutdale: 109° (old record: 102°, 2006) ***New All-Time Record***
Vancouver: 90°/32.3°C (old record: 86°/30.2°C, 2002) ***New June Record***
Vancouver, WA: 108° (old record: 101°, 2006) ***New June Record; Tied All-Time Record***
Victoria, BC: 96°/35.8°C (old record: 85°/29.6°C, 2002) ***New June Record***
Yakima, WA: 104° (tied record set in 2015)

June 27, 2021:
Astoria, OR: 101° (old record: 89°, 2000) ***New June Record; Tied All-Time Record***
Aurora, OR: 112° (old record: 92°, 2003) ***New All-Time Record***
Bellingham, WA: 95° (old record: 87°, 2015) ***Tied June Record***
Dallesport, WA: 115° (old record: 105°, 2006) ***New June Record; Tied All-Time Record***
Ephrata, WA: 109° (old record: 107°, 2015)
Eugene, OR: 111° (old record: 98°, 2015) ***New All-Time Record***
Fort Nelson, BC: 98°/36.5°C (old record: 87°/30.4°C, 2015) ***New June Record***
Hermiston, OR: 114° (old record: 111°, 2015) ***New All-Time Record***
Hillsboro, OR: 109° (old record: 96°, 2000) ***New All-Time Record***
Hoquiam, WA: 103° (old record: 88°, 2000) ***New All-Time Record***
Kamloops, BC: 111°/44.0°C (old record: 99°/37.1°C, 2006) ***New All-Time Record***
Lewiston, ID: 107° (tied record set in 2015)
Lillooet, BC: 113°/44.8°C (old record: 104°/39.8°C, 2015) ***New All-Time Record***
Lytton (RCS), BC: 116°/46.6°C (old record: 104°/40.2°C, 2015) ***New All-Time Record; New National Record for Canada***
McMinnville, OR: 111° (old record: 98°, 2000) ***New All-Time Record***
Medford, OR: 113° (old record: 104°, 2015) ***New June Record***
Olympia: 105° (93°, 2015) ***New All-Time Record***
Omak, WA: 109° (old record: 107°, 2015)
Pasco, WA: 115° (old record: 111°, 2015) ***New All-Time Record***
Pendleton, OR: 112° (old record: 109°, 2015) ***New June Record***
Portland: 112° (old record: 98°, 2000) ***New All-Time Record***
Quillayute, WA: 90° (old record: 86°, 1995 and 2000)
Redmond, OR: 108° (old record: 100°, 2015) ***New June Record; Tied All-Time Record***
Roseburg, OR: 114° (old record: 101°, 2015) ***New All-Time Record***
Salem, OR: 113° (old record: 99°) ***New All-Time Record***
Seattle: 104° (old record: 92°, 2015) ***New All-Time Record***
Spokane: 102° (tied record set in 2015)
Troutdale, OR: 112° (old record: 99°, 2000) ***New All-Time Record***
Vancouver: 88°/31.1°C (old record: 79°/26.1°C, 1937)
Vancouver, WA: 112° (old record: 97°, 2000) ***New All-Time Record***
Victoria: 100°/37.7°C (old record: 85°/29.5°C, 1995) ***New All-Time Record***
Walla Walla, WA: 110° (old record: 109°, 2015)
Yakima, WA: 109° (old record: 108°, 2015) ***New June Record***

June 28, 2021:
Aurora, OR: 114° (old record: 102°, 2008) ***New All-Time Record***
Bellingham, WA: 99° (old record: 84°, 1995) ***New All-Time Record***
Dallesport, WA: 118° (old record: 104°, 1937 and 1948) ***New All-Time Record***
Ephrata: 113° (old record: 110°, 2015) ***New June Record***
Fort Nelson, BC: 94°/34.6°C (old record: 86°/30.2°C, 1982)
Hermiston, OR: 114° (old record: 107°, 2015) ***Tied All-Time Record***
Hillsboro, OR: 114° (old record: 101°, 2008) ***New All-Time Record***
Hoquian, WA: 95° (old record: 86°, 2008)
Kamloops, BC: 114°/45.8°C (old record: 100°/37.7°C, 2008) ***New All-Time Record***
Lewiston, ID: 112° (old record: 111°, 2015) ***New June Record***
Lillooet, BC: 114°/45.6°C (old record: 103°/39.3°C, 2015)
Lytton (RCS), BC: 118°/47.9°C (old record: 103°/39.6°C, 2008)***New All-Time Record; New National Record for Canada***
McMinnville, OR: 114° (old record: 100°, 2003) ***New All-Time Record***
Medford, OR: 115° (old record: 103°, 2003 and 2008) ***Tied All-Time Record***
Olympia, WA: 110° (old record: 92°, 1978, 2003 and 2008) ***New All-Time Record***
Omak, WA: 112° (old record: 110°, 2015) ***New June Record***
Pasco, WA: 114° (old record: 111°, 2015)
Pendleton: 113° (old record: 109°, 2015) ***New June Record***
Portland: 116° (old record: 100°, 2008) ***New All-Time Record***
Quillayute, WA: 110° (old record: 92°, 1995) ***New All-Time Record***
Redmond, OR: 110° (old record: 97°, 2008) ***New All-Time Record***
Salem, OR: 117° (old record: 101°, 2008) ***New All-Time Record***
Seattle: 108° (old record: 91°, 1995 and 2008) ***New All-Time Record***
Spokane: 105° (tied record set in 2015) ***Tied June Record***
Troutdale, OR: 116° (old record: 99°, 2003) ***New All-Time Record***
Vancouver: 89°/31.7°C (old record: 87°/30.5°C, 1995)
Vancouver, WA: 115° (old record: 101°, 2008) ***New All-Time Record***
Victoria, BC: 103°/39.4°C (old record: 89°/31.7°C, 1995) ***New All-Time Record***
Walla Walla, WA: 113° (tied record set in 2015) ***Tied June Record***
Yakima, WA: 109° (old record: 108°, 2015) ***Tied June Record***

June 29, 2021:
Boise: 105° (tied record set in 2008)
Dallesport, WA: 107° (tied record set in 2008)
Ephrata, WA: 116° (old record: 103°, 2008) ***New All-Time Record***
Fort Nelson, BC: 97° (old record: 92°/33.5°C, 2015)
Hermiston, OR: 118° (old record: 102°, 2015) ***New All-Time Record***
Kamloops, BC: 117°/47.3°C (old record: 102°/39.1°C, 2008) ***New All-Time Record***
Lewiston, ID: 115° (old record: 108°, 1939) ***New June Record***
Lillooet, BC: 116°/46.8°C (old record: 103°/39.2°C, 2008) ***New All-Time Record***
Lytton (RCS), BC: 121°/49.6°C (old record: 104°/40.0°C, 2008) ***New All-Time Record; New National Record for Canada***
Omak, WA: 117° (old record: 101°, 1926 and 2008) ***New All-Time Record***
Pasco, WA: 113° (old record: 105°, 2008)
Pendleton, OR: 117° (old record: 102°, 1904 and 2008) ***New June Record***
Portland: 93°
Redmond, OR: 112° (old record: 100°, 2008) ***New All-Time Record***
Spokane: 109° (old record: 98°, 1939) ***New All-Time Record***
Vancouver: 90°/32.4°C (old record: 83°/28.6°C, 1995)
Walla Walla, WA: 116° (old record: 105°, 2008) ***New All-Time Record***
Yakima, WA: 113° (old record: 103°, 1948) ***New All-Time Record***

June 30, 2021:
Ephrata, WA: 108° (old record: 102°, 1987 and 2008)
Fort Nelson, BC: 89°/31.4°C (old record: 87°/30.8°C, 1982)
Fort Smith, NT: 104°/39.9°C (old record: 89°/31.7°, 1955) ***All-Time Record***
Hermiston, OR: 109° (old record: 105°, 2008)
Kamloops, BC: 116°/46.6°C (old record: 101°/38.5°, 2008)
Lewiston, ID: 113° (old record: 108°, 1924)
Lillooet, BC: 108°/42.2°C (old record: 99°/37.1°C, 2008)
Omak, WA: 114° (Old record: 107°, 1924)
Pasco, WA: 113° (old record: 104°, 2008)
Spokane: 104° (old record: 99°, 1924)
Walla Walla, WA: 108° (old record: 104°, 1987)
Yakima, WA: 108° (old record: 102°, 2008)

Most impressive of all, the extreme heatwave set new national high temperature records in Canada on three consecutive days at Lytton, a small village located in the Fraser River Valley in British Columbia.

Lytton's "Off the Charts" Heat:

Source: Dr. Robert Rohde, BerkeleyEarth (https://twitter.com/RARohde/status/1410157638109872134)

Enormous tragedy also followed closely on the heels of the historic heat in Lytton. An extremely dangerous and fast-moving wildfire swept into the small village on June 30th forcing a mass evacuation. The Vancouver Sun reported that the fire resulted in a "'catastrophic' destruction of homes, businesses and vehicles."

 

[skierinvermont]

On 6/30/2021 at 1:56 PM, psv88 said:

No. This was a once in a thousand year + event. My gut tells me Portland will not exceed this temp in our lifetimes.

This was a 1 in a 200,000 year event at Portland on a 1950-1981 century baseline if Don's numbers are right (z=4.37). On a 1991-2000 baseline it was a 1 in 50,000 year event. It's likely a 1 in 15,000 year event on a current baseline. By the time I die (~2080 life exp) I'd expect it to be roughly a 1 in 50 year event, with temperatures slightly below these values occurring every few years.

I'd agree it's very unlikely to recur in the next 10 years. I'd say 50/50 Portland exceeds in my lifetime. Don correct me if I have misunderstood your sigma values.

[Roger Smith]

Actually words CAN describe this heat wave, I just can't post them here. 

Just got in from a stroll around town, it's almost as hot again but quite a gusty south wind with radar echoes about 100 miles southwest near Grand Coulee WA, probably heading west of my location later this afternoon. Somewhat apprehensive about living in the middle of unbroken forest in every direction, there's no commercial logging except on a very restricted basis near the border, and the forest extends about 50 miles across the border before it thins out to a chaparral style mix of grasslands, scorched tree stumps and valleys full of cottonwood. There are landscapes like that closer to our Okanagan valley also. 

For people not that familiar with our geography, if you know the layout of inland WA, the Cascades extend a short distance into BC then a range moves west to join the Coast Ranges which are much higher here than in the Olympic Peninsula. Then you have various river valleys and plateaux between those mountains and the Okanagan valley which is quite wide and contains a long freshwater lake almost a hundred miles long and a few miles wide. Kelowna BC is about halfway up this lake on both sides, mostly east; Vernon is at the north end and there's a secondary chain of lakes ending up in the south end of that city; Penticton is on the south end of the lake. Further south, there are two more smaller lakes and the weather station at Osoyoos. This is semi-desert country with a lot of commercial vineyards and fruit orchards. 

Kamloops is in a fairly similar setting further north in the Thompson valley. That river drains most of east-central BC and joins the Fraser near Ashcroft (north of Lytton and Lillooet). To the east of Kamloops is Shuswap Lake and Salmon Arm. From there south to the U.S. border is a secondary mountain range, the Monashees with peaks in the 8 to 10 k range, not as high or alpine as the Selkirks or Rockies which are parallel ranges further east. Between the Monashees and the Selkirks, the Columbia River has been dammed near Castlegar to form the Arrow Lakes. the weather station at Nakusp is on the north Arrow Lake and gets slight modification as you'll see from its max and records in the past. Between the Selkirks and another similar range, the Purcells, Kootenay Lake is situated and it's a natural feature of the Kootenay (Kootenai on your side) River. That river rises in southeast BC, flows south into Montana, northwest back into BC from Idaho, and joins the Columbia at Castlegar. All of these regions I have mentioned east of the Okanagan are forested and more temperate than semi-arid but near the U.S. border there are patches of open ranching country that is semi-arid (around Grand Forks and Trail). 

So when people ask, how can it get so hot that far north, really it's the same landscape as you would see in eastern WA, and our elevations are sometimes a bit lower than analogous locations there. Once it gets superheated over inland Pac NW our climate blends in and merges with that climate. This past situation was a bit unusual in that the heat dome did not just have a leisurely connection to the desert southwest like most of our heat waves (and they top out around 38 C as the records being broken will illustrate). This one was separated by a trough near Boise ID to Salt Lake City UT, so that a bit of a relatively cool pocket formed over parts of e NV and central UT into CO and nw NM, ne AZ. This is a fairly unusual midsummer setup although I have seen variations on it before. One of our trips south in Aug 2014 went from heat and sunshine here into cloud and heavy showers in NV and UT, by the time we got to Bryce Canyon it was only 20 C and wet for a day. 

Looking into the posting of pictures, the limits here are so small even my cheap camera shots are too big to download and I seem to have lost the programs I used to have available to resize pictures. 

[bdgwx]

 

[skierinvermont]

As bad as the air gets with the CA OR ID fires... my fear is it will only get worse when WA and BC really start burning 20 or 30 years from now. At a certain point the trees up there which are adapted for cooler weather are just going to die enmasse.