Our region's extreme run

[RodneyS]

On 1/24/2019 at 2:16 PM, RodneyS said:

DCA just recorded its first 1-inch or more precipitation day of 2019, after a record-breaking 24 such days last year.  More remarkably, the amount of precipitation there since July 1, 2018 is now more than 44 inches.  The previous record for any July-March period was only 43.81 inches, set during July 1934-March 1935.  So, we have exceeded that total with more than two months still to go. 

Another DC precipitation record has just fallen.  The previous DC record precipitation from the second half of one year to the first half of the following year was 62.16 inches, set during July 1885 to June 1886.  With 0.62 inches already recorded at DCA tonight, the July 2018-June 2019 total there is 62.53 inches and counting. 

[PrinceFrederickWx]

BWI is currently tied for 10th hottest July (and 10th hottest month). That’s probably going to be an outright win for 10th (or possibly even a tie for 9th) after today.

Four of BWI’s top ten hottest July’s (and top ten hottest months) have occurred in this decade.

[PrinceFrederickWx]

September finished tied for 5th hottest and also 2nd driest at BWI. 

This is the decade of hot Septembers at BWI- 2018 is now tied for 11th hottest and 2016 is now ranked 16th hottest. It will be interesting to see how the 1991-2020 norms affect September, as there as only been one this decade with below average temps- 2013, which was still only -0.1.

@RodneyS or @MN Transplant how did DCA/IAD do?

[Winter Wizard]

6 hours ago, PrinceFrederickWx said:

September finished tied for 5th hottest and also 2nd driest at BWI. 

This is the decade of hot Septembers at BWI- 2018 is now tied for 11th hottest and 2016 is now ranked 16th hottest. It will be interesting to see how the 1991-2020 norms affect September, as there as only been one this decade with below average temps- 2013, which was still only -0.1.

@RodneyS or @MN Transplant how did DCA/IAD do?

DCA: +5.5 and 0.25", good for 2nd warmest and 3rd driest
IAD: +4.6 and 0.41", good for 3rd warmest and 2nd driest

[RodneyS]

1 hour ago, Winter Wizard said:

DCA: +5.5 and 0.25", good for 2nd warmest and 3rd driest
IAD: +4.6 and 0.41", good for 3rd warmest and 2nd driest

Minor correction for DCA:  According to the Capital Weather Gang, September 2019 was the 3rd warmest and 4th driest September in DC history; see https://www.washingtonpost.com/weather/2019/10/01/washington-just-posted-its-rd-warmest-th-driest-september-record

[yoda]

From today's AFD re September rainfall records:

Quote

Here are the rankings for driest Septembers on record.

Washington, DC area (Ronald Reagan Washington National Airport, DCA)
1. 0.11 inches (2005)
2. 0.14 inches (1884)
3. 0.20 inches (1967)
4. 0.25 inches (2019)
5. 0.32 inches (1977)
1981-2010 normal monthly rainfall for September: 3.72 inches

Note: Weather records for the Washington, DC area have been kept at
what is now Ronald Reagan Washington National Airport (DCA) since
1941. The official weather record consists of that data back to
1945, and additional precipitation records observed in downtown
Washington, DC extend the period of record back to 1871.

Baltimore MD area (Baltimore-Washington International Thurgood
Marshall Airport, BWI)
1. 0.09 inches (1884)
2. 0.16 inches (2019)
3. 0.21 inches (1967)
4. 0.32 inches (1906)
5. 0.35 inches (2007)
1981-2010 normal monthly rainfall for September: 4.03 inches

Note: Weather records for the Baltimore, MD area have been kept at
what is now Baltimore-Washington International Thurgood Marshall
Airport (BWI) since 1950. Additional precipitation records observed
in downtown Baltimore extend the period of record back to 1871.

Sterling/Dulles VA area (Washington Dulles International Airport,
IAD)
1. 0.15 inches (2005)
2. 0.41 inches (2019)
3. 0.62 inches (1967)
4. 0.78 inches (1978)
5. 0.93 inches (2014)
1981-2010 normal monthly rainfall for September: 3.92 inches

Note: Weather records for the Sterling/Dulles VA area have been kept
at what is now Washington Dulles International Airport (IAD) since
1960.

[RodneyS]

October 2, 2019 is in the record books for the hottest October maximum in DC, Baltimore, and Dulles.  The respective maximums today were 98, 98, and 96. The previous record for DC and Baltimore was set on October 5, 1941, with respective maximums of 96 and 97.  The previous record for Dulles was set October 9, 2007, at 94. 

[PrinceFrederickWx]

Tied for 11th hottest October at BWI.

[RodneyS]

On 2/28/2018 at 6:55 PM, RodneyS said:

February 2018 at DCA was not as warm as last year's record-setter of 47.7 degrees, but its 45.3 degree average was good enough for 3rd place all-time in DC, behind only last year and February 1976 (46.9).  The warm finish to the meteorological winter brought the 3-month average to 40.0 degrees, with a true 90-day average of 39.9.  Each average was 3.9 degrees below last year's respective averages, but still warm enough for the 29th all-time warmest meteorological winter in DC.

February 2020 averaged 43.8 degrees at DCA, with the meteorological winter there at 42.8 degrees, each 7th on the all-time DC list, although February 1984 also averaged 43.8.

[RodneyS]

On 3/20/2012 at 12:42 PM, RodneyS said:

 

Eight years ago today, I posted on this thread -- http://www.americanw...h-on-record-dca: "The final numbers for the 2011/12 astronomical and composite winters are 45.9 and 45.6 degrees, respectively. Thus, the record for the warmest astronomical winter was broken by 2.2 degrees and the record for the warmest composite winter was broken by 1.6 degrees. When the astronomical winter warm record was last broken (in 1989-90), it was only by 0.2 degrees, and when the composite winter warm record was last broken (in 2001-02), it was only by 0.9 degrees."  

This season, the astronomical winter (December 21-March 20, on average) averaged 45.5 at DCA , and so it fell only 0.4 degrees short of 2011/12.  And the composite winter (December 1-March 20, on average) averaged 44.6 at DCA, and so it fell 1.0 degree short of 2011/12.  Both averages are good enough for second warmest in DC history.

 

 

[RodneyS]

On 3/20/2020 at 9:52 PM, RodneyS said:

Eight years ago today, I posted on this thread -- http://www.americanw...h-on-record-dca: "The final numbers for the 2011/12 astronomical and composite winters are 45.9 and 45.6 degrees, respectively. Thus, the record for the warmest astronomical winter was broken by 2.2 degrees and the record for the warmest composite winter was broken by 1.6 degrees. When the astronomical winter warm record was last broken (in 1989-90), it was only by 0.2 degrees, and when the composite winter warm record was last broken (in 2001-02), it was only by 0.9 degrees."  

This season, the astronomical winter (December 21-March 20, on average) averaged 45.5 at DCA , and so it fell only 0.4 degrees short of 2011/12.  And the composite winter (December 1-March 20, on average) averaged 44.6 at DCA, and so it fell 1.0 degree short of 2011/12.  Both averages are good enough for second warmest in DC history.

March 2020 averaged 53.2 degrees at DCA, good enough for 5th on the all-time warmest March DC list, with March 2012 warmest at 56.8.  Further, 1Q 2020 averaged 46.5 at DCA, which was second on the all-time warmest 1Q DC list, with 2012 again warmest, at 47.3.  Moreover, for the 12 months ending March 31st, April 2019-March 2020 set the all-time record at 61.7 degrees, edging out April 2011-March 2012, which averaged 61.6.

 

 

 

[RodneyS]

I just posted this on the Capital Weather Gang webpage, in response to Ian Livingston's article at https://www.washingtonpost.com/weather/2020/04/28/pm-update-some-more-showers-tonight-much-warmer-wednesday

Today marked the 15th consecutive day at DCA without a 70+ degree reading.  The only other April 14-28 period where that happened in DC weather history was 1875.  However, as Ian notes, the current run appears over, as tomorrow is forecast to be at least 70.  In 1875, the run ended one day later, on April 30th, with a reading of 72.  Still, there is a big difference between these two Aprils.  April 1875 averaged only 48.0 degrees, the second coldest April in DC history, whereas this April has averaged 54.8 so far, only slightly below the 1871-2019 historical April average of 55.3.  By the way, 1874 was the coldest April in DC history, at 47.1, and the only April day that reached 70+ that year was the 15th, at 72 degrees.

[RodneyS]

On 4/28/2020 at 6:02 PM, RodneyS said:

I just posted this on the Capital Weather Gang webpage, in response to Ian Livingston's article at https://www.washingtonpost.com/weather/2020/04/28/pm-update-some-more-showers-tonight-much-warmer-wednesday

Today marked the 15th consecutive day at DCA without a 70+ degree reading.  The only other April 14-28 period where that happened in DC weather history was 1875.  However, as Ian notes, the current run appears over, as tomorrow is forecast to be at least 70.  In 1875, the run ended one day later, on April 30th, with a reading of 72.  Still, there is a big difference between these two Aprils.  April 1875 averaged only 48.0 degrees, the second coldest April in DC history, whereas this April has averaged 54.8 so far, only slightly below the 1871-2019 historical April average of 55.3.  By the way, 1874 was the coldest April in DC history, at 47.1, and the only April day that reached 70+ that year was the 15th, at 72 degrees.

April 2020 at DCA averaged 55.3 degrees -- the same as the 1871-2019 historical average.  However, precipitation at 6.30 inches was double the DC April historical average of 3.15 inches.  In fact, it was the 7th rainiest April in DC history, with the rainiest being 9.13 inches in 1889.

[RodneyS]

On 4/28/2020 at 6:02 PM, RodneyS said:

I just posted this on the Capital Weather Gang webpage, in response to Ian Livingston's article at https://www.washingtonpost.com/weather/2020/04/28/pm-update-some-more-showers-tonight-much-warmer-wednesday

Today marked the 15th consecutive day at DCA without a 70+ degree reading.  The only other April 14-28 period where that happened in DC weather history was 1875.  However, as Ian notes, the current run appears over, as tomorrow is forecast to be at least 70.  In 1875, the run ended one day later, on April 30th, with a reading of 72.  Still, there is a big difference between these two Aprils.  April 1875 averaged only 48.0 degrees, the second coldest April in DC history, whereas this April has averaged 54.8 so far, only slightly below the 1871-2019 historical April average of 55.3.  By the way, 1874 was the coldest April in DC history, at 47.1, and the only April day that reached 70+ that year was the 15th, at 72 degrees.

 In response to a comment on the Capital Weather Gang webpage arguing that we had a normal Spring, I posted this reply at https://www.washingtonpost.com/weather/2020/05/13/warm-weather-arrive-abruptly-east-this-week-may-just-be-tease-some: I wouldn't exactly call this Spring normal, particularly for the last 30 days.  The maximum temperature at DCA during April 14-May 13 averaged 63.6 degrees, the 6th coldest all-time in DC for that period and the coldest since 1882, which averaged 62.2.  The coldest all-time was 1875, which averaged 60.8; and the warmest was 1985, which averaged 79.0.

[wxdude64]

1917 must have been a doozy! I (and all the CO-Ops within 30 miles) are running -8.5 to -10 for the month to date and the stations that have been around a while have 1917 one to 2.5 degrees colder!! Crazy.

[RodneyS]

13 hours ago, wxdude64 said:

1917 must have been a doozy! I (and all the CO-Ops within 30 miles) are running -8.5 to -10 for the month to date and the stations that have been around a while have 1917 one to 2.5 degrees colder!! Crazy.

Based on the metric I was using, 1917 wasn't quite as cold as this year in DC, with an average maximum temperature of 63.8 during April 14-May 13.  However, May 1917 maximums averaged only 68.8, 4th coldest of all time. And the overall average May 1917 temperature was only 59.6, just 0.4 degrees above the all-time coldest DC May, which was 1907.

[wxdude64]

13 hours ago, RodneyS said:

Based on the metric I was using, 1917 wasn't quite as cold as this year in DC, with an average maximum temperature of 63.8 during April 14-May 13.  However, May 1917 maximums averaged only 68.8, 4th coldest of all time. And the overall average May 1917 temperature was only 59.6, just 0.4 degrees above the all-time coldest DC May, which was 1907.

Must have been colder back here, all the stations that old or older have 1917 WAY below anything else. Several stations go back into 1890's.

[wxdude64]

So...Roanoke finally had a below 90 high today (89 lol), so that stops the streak at 29 consecutive 90 or above days. That is the new record, breaking 1966's 22 days in a row by a good bit.

[RodneyS]

On 7/30/2020 at 7:40 PM, wxdude64 said:

So...Roanoke finally had a below 90 high today (89 lol), so that stops the streak at 29 consecutive 90 or above days. That is the new record, breaking 1966's 22 days in a row by a good bit.

DCA recorded 28 90-degree-plus days this month, breaking the DC record of 25 set in July 2011.  However, the longest streak at 20 days fell one-day short of the 1980 and 1988 record streaks of 21 days.  Also, the July 2020 average temperature of 83.9 at DCA fell short of the July 2011 record average monthly temperature of 84.8, as well as the July 2012 average of 84.0.

[PrinceFrederickWx]

BWI tied for 3rd hottest November (along with 1985 and 1946) at 52.4 degrees. Only 1948 and 1931 were hotter at 53.0 and 54.7 degrees, respectively.

[RodneyS]

1 hour ago, PrinceFrederickWx said:

BWI tied for 3rd hottest November (along with 1985 and 1946) at 52.4 degrees. Only 1948 and 1931 were hotter at 53.0 and 54.7 degrees, respectively.

And DCA tied for the 4th hottest November (along with 1985) at 54.3 degrees. 2001 is # 1, at 54.8, and 1975 and 1979 are tied for 2nd at 54.4. 

[WxUSAF]

Going to extend this record another 300+ days and therefore beat the previous record by 700+ days.

 

[MN Transplant]

54 minutes ago, WxUSAF said:

Going to extend this record another 300+ days and therefore beat the previous record by 700+ days.

 

Going to need to update those gardening maps.  Maybe we can grow some tropical fruit.

[RodneyS]

9 minutes ago, MN Transplant said:

Going to need to update those gardening maps.  Maybe we can grow some tropical fruit.

In yesterday's Capital Weather Gang article,  Ian was touting this morning as the day DCA and IAD would reach their 2020-21 seasonal winter minimums.  That happened at IAD, with a morning low of 16, but failed to happen at DCA, where the seasonal minimum remains 23, which occurred on December 26th.  If these minimums hold for the remainder of the winter, they would break the seasonal high minimum records established a year ago. For DCA, that is 22, and for IAD, 15.   

[wxdude64]

36 minutes ago, RodneyS said:

In yesterday's Capital Weather Gang article,  Ian was touting this morning as the day DCA and IAD would reach their 2020-21 seasonal winter minimums.  That happened at IAD, with a morning low of 16, but failed to happen at DCA, where the seasonal minimum remains 23, which occurred on December 26th.  If these minimums hold for the remainder of the winter, they would break the seasonal high minimum records established a year ago. For DCA, that is 22, and for IAD, 15.   

Crazy the way DCA holds heat.... Course one day in early March they'll get a 19 to screw up going for 1000.

[RodneyS]

6 hours ago, wxdude64 said:

Crazy the way DCA holds heat.... Course one day in early March they'll get a 19 to screw up going for 1000.

DCA is the champion of high minimums year-round.  However, it's interesting to note that both DCA and IAD have added four degrees in the last decade to their respective high winter minimums.  Coming into 2012, DCA's record high winter minimum was 18 degrees and IAD's was 11.  Now, DCA's is 22 and IAD's is 15, with each quite possibly breaking those records by another degree this season.   

[RodneyS]

On 2/21/2021 at 2:38 PM, RodneyS said:

DCA is the champion of high minimums year-round.  However, it's interesting to note that both DCA and IAD have added four degrees in the last decade to their respective high winter minimums.  Coming into 2012, DCA's record high winter minimum was 18 degrees and IAD's was 11.  Now, DCA's is 22 and IAD's is 15, with each quite possibly breaking those records by another degree this season.   

I think it's now fair to say that both DCA and IAD have broken their high winter minimum temperature records set just last winter.  DCA's record high winter minimum temperature is now 23 degrees, and IAD's is now 16.  However, I discovered that way back in the winter of 1952-53, and more recently in the winter of 2001-02, the DCA minimum was 19.  So, that 19-degree record DCA (and DC, back to 1872) high winter minimum stood until last winter, when it was broken by three degrees. This winter, that record high minimum was broken by another degree, as was also true at IAD. 

[RodneyS]

Today has an interesting distinction, with a high of 59 at DCA, which was recorded at 12:33 AM.  Officially, that is the second lowest DC maximum ever for May 29th, with May 29, 1893 being the record-holder at 58 degrees.  However, that record is likely the result of the temperature not being observed when the day dawned, because the official DC temperature range for May 28, 1893 is 60-69 degrees. If that is correct, which I think is likely, May 29th, 1893 had to begin with a temperature of at least 60 degrees.  So today's high of 59 is likely the new unofficial record-holder for lowest DC maximum on May 29th. 

[PrinceFrederickWx]

I didn't realize August was 6th hottest at BWI.

[RodneyS]

On 12/30/2015 at 11:55 AM, Ian said:

This month yo

 

December 2021 at DCA could not match December 2015's average of 51.2 degrees, but it was the second warmest December in DC history at 47.6 degrees -- 3.6 degrees cooler, but 2.0 degree warmer than the December record holders prior to 2015, which were December 1889 and 1984 (45.6).  That also makes December 2021 the fourth warmest meteorological winter month in DC history, behind only December 2015, January 1950 (48.0), and February 2017 (47.7).