Phoenix Experiences its Hottest June on Record

[donsutherland1]

8 hours ago, GaWx said:

Don,

 Impressive, indeed!
 How much would you guess has the increased UHI been a factor? Metro LV now ~3 million, which is nearly double 2005 pop. It’s 10 x pop of 50 yrs ago.

https://www.macrotrends.net/global-metrics/cities/23043/las-vegas/population

Probably, around half given trends at some rural sites. Unfortunately, there are no nearby USCRN sites. Growing urbanization has played an important role in driving the warming in Las Vegas and Reno, on top of background warming from climate change.

[bdgwx]

It looks like Las Vegas is on track to have it's hottest month on record. If the official NWS forecast verifies and assuming I added everything up correctly they will end with an average of 99.2 F which would beat 2023's record of 97.3 F.

Personal note...My family is wrapping up a vacation in the region. We started in California's central valley and drove into parts of Nevada, Arizona, and Utah and are flying back to St. Louis from Las Vegas. It has been brutally hot the whole time almost everywhere except for the slight reprieve while in the mountains. Death Valley was particularly insidious. Atypical of the region it was actually modestly humid so the heat index matched the temperature when we drove through. We were confused as we approached from Lone Pine, CA seeing runners. After a bit of research we realized we were unintentionally spectating the 2024 Badwater Ultramarathon where 100 of the word's toughest superhumans race from Badwater Basin (lowest point in CONUS) to Mt Whitney (highest point in CONUS) and is considered the world's hardest foot race. I tip my cap to those who participated in that race,

 

[gallopinggertie]

It has been hot in the Pacific Northwest, too. Here in Portland, Oregon, July has averaged 75.2 degrees so far which is 5.4 degrees above normal. There were three straight days of 100-plus highs earlier this month.

Portland and Seattle both have Csb climates, aka warm-summer Mediterranean. But Portland’s current hottest average month, July, is only a couple degrees from crossing the 72-degree threshold that would push it to Csa, aka hot-summer Mediterranean. 

At this rate, Portland will probably be Csa in a couple decades, and Seattle might follow around 2070 or something. 

Though it’s hard to imagine, many climate models forecast huge shifts in these climate zones. In 2100 Chicago may be Cfa (“humid subtropical”, though it would still have chilly winters, just much less cold than now), and warm-summer continental climates (Dfb) will likely displace subarctic climates throughout much of Canada. 

[donsutherland1]

16 hours ago, gallopinggertie said:

It has been hot in the Pacific Northwest, too. Here in Portland, Oregon, July has averaged 75.2 degrees so far which is 5.4 degrees above normal. There were three straight days of 100-plus highs earlier this month.

Portland and Seattle both have Csb climates, aka warm-summer Mediterranean. But Portland’s current hottest average month, July, is only a couple degrees from crossing the 72-degree threshold that would push it to Csa, aka hot-summer Mediterranean. 

At this rate, Portland will probably be Csa in a couple decades, and Seattle might follow around 2070 or something. 

Though it’s hard to imagine, many climate models forecast huge shifts in these climate zones. In 2100 Chicago may be Cfa (“humid subtropical”, though it would still have chilly winters, just much less cold than now), and warm-summer continental climates (Dfb) will likely displace subarctic climates throughout much of Canada. 

Portland is also seeing a noticeable increase in 90-degree days.

[TheClimateChanger]

On 7/26/2024 at 9:17 PM, gallopinggertie said:

It has been hot in the Pacific Northwest, too. Here in Portland, Oregon, July has averaged 75.2 degrees so far which is 5.4 degrees above normal. There were three straight days of 100-plus highs earlier this month.

Portland and Seattle both have Csb climates, aka warm-summer Mediterranean. But Portland’s current hottest average month, July, is only a couple degrees from crossing the 72-degree threshold that would push it to Csa, aka hot-summer Mediterranean. 

At this rate, Portland will probably be Csa in a couple decades, and Seattle might follow around 2070 or something. 

Though it’s hard to imagine, many climate models forecast huge shifts in these climate zones. In 2100 Chicago may be Cfa (“humid subtropical”, though it would still have chilly winters, just much less cold than now), and warm-summer continental climates (Dfb) will likely displace subarctic climates throughout much of Canada. 

Looks like the border between warm summer and hot summer subtypes is actually 22C, which is 71.6F.

Looking at historical data, the "normal" July mean at PIT (Pittsburgh International) was 71.9F in the 1960s and in the 1980s climatology. The 1960s climatology was based, in part, on a smaller POR and comparative data to infill since records didn't begin until 1952. I believe the 1970s climatology had the mean at 72.3F. Technically hot summer continental (Dfa), albeit bordering on warm summer continental (Dfb). Today is solidly hot summer continental (Dfb). The more significant change coming soon - at least as far as the Koppen classification is concerned - will be the transition to humid subtropical climate (Cfa). Based on the data presented below, I would surmise that this transition will occur within the next 20-25 years (extrapolating from trends over recent decades).

Looking at data for the last 10 years, we can see the mean of the coldest month is 29.9F over that period. Above the traditional -3C criteria, but still below the 0C criteria typically used for North American climates.

60 miles to the south, we can see Morgantown, WV has averaged 32.3F in its coldest month over the past 30 years, making it fully Cfa by all metrics.

By contrast, the 30-year mean from 1956 to 1985 was 28.3F, so that's a 4F rise in just 40 years. Heck, even February was colder than recent Januarys back then. Interestingly, it that period, even Morgantown was only about 0.5C above the border for warm summer continental (Dfb).

 

 

[TheClimateChanger]

On 7/26/2024 at 9:17 PM, gallopinggertie said:

It has been hot in the Pacific Northwest, too. Here in Portland, Oregon, July has averaged 75.2 degrees so far which is 5.4 degrees above normal. There were three straight days of 100-plus highs earlier this month.

Portland and Seattle both have Csb climates, aka warm-summer Mediterranean. But Portland’s current hottest average month, July, is only a couple degrees from crossing the 72-degree threshold that would push it to Csa, aka hot-summer Mediterranean. 

At this rate, Portland will probably be Csa in a couple decades, and Seattle might follow around 2070 or something. 

Though it’s hard to imagine, many climate models forecast huge shifts in these climate zones. In 2100 Chicago may be Cfa (“humid subtropical”, though it would still have chilly winters, just much less cold than now), and warm-summer continental climates (Dfb) will likely displace subarctic climates throughout much of Canada. 

It's always surprising to me how much colder Chicago is than Cleveland in the wintertime. Being upwind versus downwind of the Great Lakes makes a huge difference.

1956-1985 at CLE (Dfb, bordering on Dfa):

Last 10 years below. Very solidly Dfa. The mean of the coldest month is 1.6F warmer than the mean of the coldest month at Morgantown, West Virginia, from 1956-1985. Looks to be on the same path as PIT. Likely Cfa by mid-century using 0C definition.

[donsutherland1]

Phoenix had its second hottest July and month on record. It tied the July and monthly records for most 100° highs, 80° lows, and 90° lows. For the first time, it experienced 31 100° high temperatures following a June with 30 100° high temperatures. Through July 31st, it had an ongoing streak of 51 consecutive 80° or above low temperatures (old record: 51 days, July 1-August 20, 2023). Its ongoing streak of 66 consecutive 100° highs ranked as the second longest on record. It ended July with a streak of 57 consecutive 105° or above highs (old record: 56 days, June 24-August 18, 2023).

Numerous Western cities saw their hottest July and month on record.

[gallopinggertie]

It’s official: Portland, Oregon saw their hottest July on record this year. Average temperature was 74.7, 4.5 degrees above average. The second hottest July was 74.1 degrees in 1985, so it was by a significant margin. August 2023 was the hottest month of all-time. Climate change is really setting in here…

ETA: Portland hasn’t really experienced rapid growth over the past few decades (compared to Las Vegas, say), so blaming this on urban heat island would be a stretch. 

[Typhoon Tip]

https://phys.org/news/2024-08-japan-hottest-july-began.html

[donsutherland1]

Phoenix’s record streak of 80-degree lows ended today.

[Bhs1975]

Phoenix’s record streak of 80-degree lows ended today.

And the highest 3 are in the last 13 years.


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[donsutherland1]

35 minutes ago, Bhs1975 said:

And the highest 3 are in the last 13 years.


.

Phoenix has been rewriting is record book, especially since 2020.