Our region's extreme run

[RodneyS]

On 5/20/2018 at 9:30 PM, GramaxRefugee said:

I guess I should have just listed that AFD, so here it is (sorry)

It has been an unusually wet pattern over the last week. For DCA
(Reagan National), there has been at least 1/4" of rain each of
the last 7 days. This is the longest streak on record. The previous
longest was 5 days in 2011, 2009, 1975, 1950, 1942, and 1937.
Precipitation records date back to 1871

I have just discovered that the above statement is not true for 0.4", as only 2011, 1975, and 1937 also had 5-day streaks of at least 0.4 inches.  However, I would have thought that the statement would have more logically read:  "It has been an unusually wet pattern over the last week. For DCA (Reagan National), there has been at least 0.4" of rain each of the last 7 days. This is the longest streak on record. The previous longest was 5 days in 2011, 1975, and 1937. Precipitation records date back to 1871."

[GramaxRefugee]

14 hours ago, RodneyS said:

You can view the May 2018 daily precipitation totals at DCA here under "Preliminary Monthly Climate Data" (Column 7 "WTR")-- https://w2.weather.gov/climate/index.php?wfo=lwx

Well heck. Now that I look at that link, it would be 8 straight days if they lowered their standard to 0.15".

I'd consider the 0.4 to be a substantial number. Perhaps the 0.15 just spreads out the various records too far, making "records" everywhere.

This isn't a particular record I've looked closely at before.  So, I'm sort of stumbling through the high weeds.

[RodneyS]

13 minutes ago, GramaxRefugee said:

Well heck. Now that I look at that link, it would be 8 straight days if they lowered their standard to 0.15".

I'd consider the 0.4 to be a substantial number. Perhaps the 0.15 just spreads out the various records too far, making "records" everywhere.

This isn't a particular record I've looked closely at before.  So, I'm sort of stumbling through the high weeds.

You're on to something.  May 12-19, 2018 was indeed the first time in DC weather history that eight straight days each recorded at least 0.15" of precipitation.  The previous record for that amount or more was seven straight days, set in July 1938 and equaled in July 1941; see http://xmacis.rcc-acis.org/#.  Click on that link, then select "Single Station" and click on "Consecutive Days."  For "Criteria" select "Precipitation" then type in (more or equal to) "0.15."  Then select the "Washington Area" station and click "Go."  

As I just posted to an article on the Washington Post's Capital Weather Gang:  

"Rainy to be sure, but to put things in perspective, DC's record single-day rainfall is 6.39 inches, on August 23, 1933. More recently, DCA recorded 9.08 inches during the five-day period September 22-26, 1975."

[RodneyS]

On 5/31/2017 at 9:07 PM, RodneyS said:

May 2017 had the distinction of being the first month in exactly one year to be: (a) below the 1981-2010 DCA temperature normal, finishing with an average of 65.5 vs. the May normal of 66.0; and (b) above the 1981-2010 DCA precipitation normal, finishing with 5.55 inches (assuming no more this evening) vs. the May normal of 3.99 inches.  January-May 2017 monthly average temperature is 53.3, placing it second all-time in DC behind January-May 2012, which averaged 54.3.

And May 2018 has the distinction of being an exceptionally warm, and yet still rainy, month in DC.  Average temperature of 72.4 degrees at DCA places it third on the all-time DC list behind only 2015 (73.2) and 1991 (73.0).  Further, the warm-up from April 2018 was 17.5 degrees, second only to April-May 1911 (18.8 degrees).  And yet precipitation was 8.73 inches, which is 6th on the all-time DC May list (May 1953 is # 1, at 10.69 inches). 

[PrinceFrederickWx]

I didn't even realize BWI got 5th hottest May... wow.

[RodneyS]

While DCA could not match BWI's record-breaking July 2018 precipitation, the 9.73 inches recorded there was 4th on the all-time DC July list, and the most since the record 11.06 inches in July 1945.  Also, the May-July 2018 total of 23.67 inches at DCA was third on the all-time list for those three calendar months, and the most in 129 years.  Only May-July 1889, at 23.83 inches, and May-July 1886, at 27.98 inches, had more precipitation in those three months.

[RodneyS]

On 8/1/2018 at 9:30 AM, RodneyS said:

While DCA could not match BWI's record-breaking July 2018 precipitation, the 9.73 inches recorded there was 4th on the all-time DC July list, and the most since the record 11.06 inches in July 1945.  Also, the May-July 2018 total of 23.67 inches at DCA was third on the all-time list for those three calendar months, and the most in 129 years.  Only May-July 1889, at 23.83 inches, and May-July 1886, at 27.98 inches, had more precipitation in those three months.

August 2018 continued the rainy trend at DCA, at 5.19 inches.  That brings the May-August 2018 precipitation total there to 28.86 inches, tied with May-August 1878 for second on the all-time DC list, behind only May-August 1886, at 30.41 inches.

[RodneyS]

On 9/1/2018 at 10:56 AM, RodneyS said:

August 2018 continued the rainy trend at DCA, at 5.19 inches.  That brings the May-August 2018 precipitation total there to 28.86 inches, tied with May-August 1878 for second on the all-time DC list, behind only May-August 1886, at 30.41 inches.

Breaking news -- literally.  With 2.76 inches of precipitation already recorded at DCA today and 3.57 so far for September 2018, the previous May-September DC record total of 32.26 inches set in 1934 has now been exceeded, at 32.43 inches.  Let's see how high we go by September 30th. 

[RodneyS]

On 9/7/2018 at 10:16 PM, RodneyS said:

Breaking news -- literally.  With 2.76 inches of precipitation already recorded at DCA today and 3.57 so far for September 2018, the previous May-September DC record total of 32.26 inches set in 1934 has now been exceeded, at 32.43 inches.  Let's see how high we go by September 30th. 

We are now up to 7.54 inches of precipitation at DCA in September 2018. That means that the previous April-September DC record of 39.91 inches established in 1889 has fallen.  The April-September 2018 total at DCA now stands at 39.99 inches, and the May-September 2018 total there is now 36.40 inches. 

[RodneyS]

On 9/23/2017 at 9:51 PM, RodneyS said:

The 2017 astronomical summer here was considerably cooler, despite the warm finish.  IAD averaged 73.5 degrees, down 4.5; and DCA averaged 77.6 degrees, down 3.5.  The IAD composite summer averaged 73.4 degrees, down 3.7; and DCA averaged 77.43 degrees, down 2.74.

I don't have IAD figures at the moment, but DCA's 2018 astronomical summer (June 21-September 23) was interesting, as the average was 79.6 degrees, good enough for 5th highest all-time on the DC list (1980 was highest at 81.7).  However, the 2018 DCA average astronomical summer maximum of 87.1 was only 26th on the all-time list, whereas the average minimum of 72.20 was 3rd, behind only 2016 (72.54) and 1980 (72.53).

[MN Transplant]

On 9/23/2018 at 9:37 PM, RodneyS said:

I don't have IAD figures at the moment, but DCA's 2018 astronomical summer (June 21-September 23) was interesting, as the average was 79.6 degrees, good enough for 5th highest all-time on the DC list (1980 was highest at 81.7).  However, the 2018 DCA average astronomical summer maximum of 87.1 was only 26th on the all-time list, whereas the average minimum of 72.20 was 3rd, behind only 2016 (72.54) and 1980 (72.53).

Rain and humidity will do that.  

[RodneyS]

 

On 9/22/2018 at 2:51 PM, RodneyS said:

We are now up to 7.54 inches of precipitation at DCA in September 2018. That means that the previous April-September DC record of 39.91 inches established in 1889 has fallen.  The April-September 2018 total at DCA now stands at 39.99 inches, and the May-September 2018 total there is now 36.40 inches. 

September 2018 precipitation at DCA was 9.73 inches, good enough for 5th on the all-time DC list.  January-September 2018 precipitation at DCA was 49.83 inches, third on the all-time list, behind only 1886 (50.65) and 1889 (50.63).

[PrinceFrederickWx]

At BWI, September finished tied for 10th hottest and 6th for rainfall.

[WxUSAF]

Wettest year on record for BWI after yesterday’s storm. Over 63” now with a month and a half left in the year.

[PrinceFrederickWx]

1 hour ago, WxUSAF said:

Wettest year on record for BWI after yesterday’s storm. Over 63” now with a month and a half left in the year.

Awesome! Where does DCA stand currently?

Paging @RodneyS and @donsutherland1 on this too if they know.

[donsutherland1]

11 minutes ago, PrinceFrederickWx said:

Awesome! Where does DCA stand currently?

Paging @RodneyS and @donsutherland1 on this too if they know.

4th with 58.58" precipitation. That record is within reach. The record is 61.33", which was established in 1889.

[Bob Chill]

And to think... there was a heated drought debate last winter.

[MN Transplant]

4 hours ago, Bob Chill said:

And to think... there was a heated drought debate last winter.

I'm still pissed at that early July torch/dry spell.

[PrinceFrederickWx]

48 minutes ago, MN Transplant said:

I'm still pissed at that early July torch/dry spell.

It’s so weird how the wettest year of my lifetime also contained one of the longest stretches of consecutive days with no precipitation IMBY.

[RodneyS]

On 11/16/2018 at 10:00 AM, donsutherland1 said:

4th with 58.58" precipitation. That record is within reach. The record is 61.33", which was established in 1889.

Not only within reach, but based on historical DC precipitation averages for November 18-December 31, we would receive another 4.28 inches through year's end, bringing the total to 62.86 inches.  Further, AccuWeather currently is projecting an additional 4.39 inches in DC through year's end. Cautionary note: While, as Don says, 1889 was the all-time wettest in DC history, oddly enough December 1889 was the driest DC December ever, at only 0.19 inches.  

[donsutherland1]

45 minutes ago, RodneyS said:

Not only within reach, but based on historical DC precipitation averages for November 18-December 31, we would receive another 4.28 inches through year's end, bringing the total to 62.86 inches.  Further, AccuWeather currently is projecting an additional 4.39 inches in DC through year's end. Cautionary note: While, as Don says, 1889 was the all-time wettest in DC history, oddly enough December 1889 was the driest DC December ever, at only 0.19 inches.  

I expect DC to set a new record. I would be quite surprised if it didn’t.

[midatlanticweather]

Little memory 

 

[RodneyS]

On 11/16/2018 at 10:00 AM, donsutherland1 said:

4th with 58.58" precipitation. That record is within reach. The record is 61.33", which was established in 1889.

With today's 1.42 inches at DCA, the yearly total now stands at an even 60 inches -- still 4th all-time in DC, but now a strong likelihood to break the record.  Even assuming no more precipitation in November, DCA would need only 1.34 inches in December to do so.  In the previous 147 Decembers in official DC precipitation history, only 17 times has precipitation been less than that.  Moreover, should DCA record only 0.08 inches more this month, that would break the all-time DC November record of 7.18 inches, set in 1877.

[donsutherland1]

9 minutes ago, RodneyS said:

With today's 1.42 inches at DCA, the yearly total now stands at an even 60 inches -- still 4th all-time in DC, but now a strong likelihood to break the record.  Even assuming no more precipitation in November, DCA would need only 1.34 inches in December to do so.  In the previous 147 Decembers in official DC precipitation history, only 17 times has precipitation been less than that.  Moreover, should DCA record only 0.08 inches more this month, that would break the all-time DC November record of 7.18 inches, set in 1877.

I believe there's a pretty good chance that both the November and annual precipitation records will be broken.

[RodneyS]

On 11/24/2018 at 8:35 PM, donsutherland1 said:

I believe there's a pretty good chance that both the November and annual precipitation records will be broken.

Not sure whether we're done for the day, but DCA already has recorded 0.44 inches of precipitation, bringing the November total to a DC record 7.55 inches.  So, one record down, one to go -- DCA needs just 0.9 inches between now and the end of the year to break the annual record.  Every December except nine in DC weather history has seen at least that much. 

[donsutherland1]

25 minutes ago, RodneyS said:

Not sure whether we're done for the day, but DCA already has recorded 0.44 inches of precipitation, bringing the November total to a DC record 7.55 inches.  So, one record down, one to go -- DCA needs just 0.9 inches between now and the end of the year to break the annual record.  Every December except nine in DC weather history has seen at least that much. 

Even as most or all of the precipitation today is done, I expect Washington to easily surpass its existing annual precipitation record.

[AfewUniversesBelowNormal]

On 11/17/2018 at 12:04 PM, Bob Chill said:

And to think... there was a heated drought debate last winter.

In 2003 was the wettest year and 2002 was the last drought.. 

[RodneyS]

On 11/26/2018 at 1:18 PM, RodneyS said:

Not sure whether we're done for the day, but DCA already has recorded 0.44 inches of precipitation, bringing the November total to a DC record 7.55 inches.  So, one record down, one to go -- DCA needs just 0.9 inches between now and the end of the year to break the annual record.  Every December except nine in DC weather history has seen at least that much. 

November 2018 precipitation at DCA appears to be finalized at 7.57 inches, leaving the annual total of 60.46 inches there just 0.87 inches shy of the 1877 DC annual record.  As 138 of 147 previous Decembers in the official precipitation history of DC have exceeded 0.87 inches, the odds of breaking the record are about 94%.  Also, the second half of 2018 (July-December) DCA precipitation total of 35.28 inches has already broken the second half record of 33.55 inches set in 1878.

Additionally, November 2018 average temperature at DCA appears finalized at 46.5 degrees, which is 3.1 degrees below the 1981-2010 normal, and the lowest average November temperature there since 1997. 

[PrinceFrederickWx]

I think DCA needs another 0.56" to break the record now, right? Looks like they had 0.32" Dec 1-2. I'm getting slightly concerned that we're gonna find a way to fail at this now lol

@RodneyS

[RodneyS]

On 12/6/2018 at 12:11 PM, PrinceFrederickWx said:

I think DCA needs another 0.56" to break the record now, right? Looks like they had 0.32" Dec 1-2. I'm getting slightly concerned that we're gonna find a way to fail at this now lol

@RodneyS

That's right -- not a done deal yet, especially with the big southern snowstorm staying to the south of DC.  For what it's worth, AccuWeather is currently projecting 1.23 inches at DCA through month's end.  However, only 0.28 inches is projected there through December 19th, and long-range precipitation forecasts are not exactly sure things.