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Posted at 02:20 PM ET, 12/01/2011

Nice, but dry November departs; 9th warmest on record


November 2011 will be remembered as a warm and dry month. But how dry and how warm, you ask? Well, for Reagan National Airport (DCA), November’s average temperature of 52.4F ranks as the 9th warmest on record dating back to 1871 (normal is 49.6F).

And it was the 51st driest of all those years with only 1.94” this entire month (normal is 3.17”).

Strangely, the decade with the most November top ten readings for warmth was the otherwise cold 1970s!

How did we spend most of our November, temperature-wise?


Temperatures by 10-degree segments during November (for lows an d highs) at Reagan National Airport (DCA)
I segmented out the days and a slight majority (43.3%) of our low temperatures was in the 40s. High temperatures had a more clear-cut winner where we spent over half of our days in the nice 60s. We can’t complain about that too much.

Remarkably, from November 20 to 29, highs were at least 60 degrees. A November ten day streak of 60+ has only happened two other times during second half of month: in 1931 and 1979 (which ranked 5th and 3rd warmest on record for the month)

Also, while the suburbs saw some frosty mornings, DCA has still not seen its first freezing temperatures (coldest for Nov 2011: 33F).

We didn’t have any record highs or lows at DCA, but we had just one over at Dulles. Our recent super-warm weather broke the high temperature record: last Sunday’s Nov 27 temperature of 70F exceeded 1976’s 68F. Those 1970s again!


Precipitation by day at Reagan National Airport (DCA)
Looking back at the precipitation side of things, our wettest weather occurred in the second half of the month. The first half was quite parched.

The big picture pattern themes were similar. We still have a La Niña in the Tropical Pacific (but weaker than last year). We still have a cold Pacific and warm Atlantic base state too. So perhaps we had the same conditions to give us a similar story to last year.

December 2011?

So far, December is looking quite tricky with plenty of weather variability in the weeks ahead. In the last two winters, we saw substantial warm ridging patterns in the North Atlantic by this point (a negative North Atlantic Oscillation), but we do not have that currently. Therefore, the odds of a warmer December are higher than the last two winters.

However, because we are in a weak La Nina winter, we could see a tremendous amount of weather variability over the coming weeks and the latest dynamic models certainly suggest it. The first seven days of December should average warmer-than-normal, while the second week could average near or slightly colder-than-normal.

I could see us getting some snow chances over the next two weeks as well, but the pattern is not ideal for major storms. I generally agree with Wes Junker’s thoughts posted earlier.

You can see the National Weather Service’s final December outlook (updated yesterday) for temperature (warm) and precipitation here: 30-day outlook

DCA Data (hat tip TerpWeather)

Average High: 61.5 (3.6 degrees warmer than average)
Average Low: 43.3 (2.2 degrees warmer than average)
Monthly Precip: 1.94” (64% of normal)
Warmest Day: 11/14 - 73 degrees
Coldest Day: 11/18 - 48 degrees
Warmest night: 11/15 - 57 degrees
Coldest night: 11/12 - 33 degrees
Wettest day: 11/22 - 0.55” of rain recorded

More information

The National Weather Service publishes nice monthly assessments usually within a week of the close of each month (should be available shortly):

You can click on your closest airport location here:

Reagan National (DCA)

Dulles Airport (IAD)

Baltimore-Washington (BWI)

Historical Washington, DC data provided by NOAA.

See also: Ian’s excellent rundown on November climatology.

By  |  02:20 PM ET, 12/01/2011

Categories:  Local Climate, Latest

 
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