How Does November Compare?

Today marks the end of November as well as the end of meteorological fall (the three month period that began September 1).  This fall has seen the continuation of the very warm and dry weather that dominated much of July and August in the Mid-Atlantic Region.  That has caused the rainfall deficit to balloon during the fall months.

Despite hot and dry months in July and August, Washington, D.C.’s annual rainfall deficit on September 1 was only 1.47”.  However, since September 1, the rainfall deficit at National Airport has ballooned to 6.40” as of November 29.  The latest Drought Monitor Index shows moderate drought conditions across much of the region.  Through November 28, only 0.26” of rain fell the entire month at National Airport.  According to the Capital Climate blog, that tied for the driest November 1 – 28 on record in Washington, D.C.  In fact, the Nation’s Capital was poised to break the 1981 record (0.29”) for driest November until yesterday. 

Some much needed rainfall occurred yesterday, with more in the forecast throughout the day today that will prevent Washingtonians from breaking the 1981 record.  Nevertheless, DC’s combined rainfall through November 29 of 3.78” for the fall season (September 1 – November 30) has positioned 2016 to be the driest fall since 2001.  As dry as it’s been this fall in the Mid-Atlantic Region, the conditions could have been worse for agricultural interests had they occurred during the spring or summer months.

Temperatures this month have been warmer than average with a monthly average temperature of 52.3 degrees at National Airport (combining daily high and low temperatures) through November 29.  November’s average temperature in Washington, D.C. is 49.6 degrees and is based on National Weather Service data from 1980-2010.  The warmest temperature in Washington, D.C. this month was 83 degrees on November 3, which set a new daily record high.  The coldest temperature to occur in the city this month was 32 degrees on November 23, while the more rural Dulles Airport’s coldest November temperature was 20 degrees (also on November 23).

NOAA’s outlook for December calls for a near average temperatures and precipitation in the Mid-Atlantic Region.  Unlike a year ago when a major El Nino contributed to a warm and wet December, an episode of La Nina has developed.  While La Nina also impacts global weather patterns, the current La Nina isn’t very strong.  My colleagues and I on the WUSA9 weather team will continue to keep you posted on the latest weather forecasts. 

Driest Observed Novembers in Washington, D.C. (measured at National Airport)

1.  0.29” (1981)
2.  0.37” (1965)
3.  0.53” (1917)
4.  0.55” (2001, 1922)
6.  0.60” (2012, 1908)
8.  0.76” (1936)
9.  0.79” (1890)
10.  0.80” (1903)