Some Cold Weather Facts for the Nation's Capital

 

Last time temperatures were in the single digits in the Nation's Capital was on January 7, 2018 when it was 8° at National Airport.

Last time high temperatures on Christmas Day remained below freezing in Washington, D.C. was in 2000 (28°).  By comparison D.C. Area residents had a high temperature of 68° on December 25, 2021, that tied with 1932 for fourth warmest Christmas.

D.C.'s coldest Christmas Day occurred in 1983 with a daily high/low temperature of 14°/3°.

D.C.’s average high and low temperatures on Christmas Day are 47°/33°.  Since 1884, Washington, D.C. has had measurable snowfall on Christmas Day only nine times or roughly every 15 years.  The last time was on December 25, 2002, with 0.2”.  However, the last time Washingtonians had snow on the ground on Christmas Day was in 2009.  That’s because the Nation’s Capital had its largest December snowfall on record the week before.

A total of 16.4” was measured at National Airport on December 18-19, 2009.  Although more than half had melted by Christmas, 7” remained on the ground, creating D.C.’s last official white Christmas.

Weather Quiz

 

Photo Credit: Robin Beal

When was the last time high temperatures in the Nation’s Capital remained below freezing on Christmas Day ?

A.  2017

B.  2009

C.  2000

D.  1989

D.C.’s Remarkable 2022 Weather

 

The Nation’s Capital had a memorable weather year in 2022 that will finish warmer and wetter than average.  That’s despite an unusually cold January and October, in addition to four consecutive drier than average months through November.  Several other significant weather occurrences took place in Washington, D.C.

January 2022 finished as D.C.’s snowiest January (and overall month) since 2016.  This past January featured several snow events that produced a monthly total of 12.3” (roughly triple D.C.’s January snowfall average of 4.9”).  Despite the snowy January, the 2021-2022 winter season still finished with below average snowfall.  January also finished as D.C.’s coldest since 2014.  D.C.’s coldest temperature of the year occurred on January 22 (16°).

March was a warmer than average month in the Nation’s Capital and finished with a monthly temperature 2.8° above average.  It was followed by a cooler and wetter than average April.  When the Wells Fargo Championship golf event took place in Potomac, Maryland in early May the weather did not cooperate.  It was unseasonably cool with highs in the 50s on May 7 and 8 and measurable rainfall on five of the first seven days of the month.

Not only did a record high of 99° occur on June 17, but that was D.C.’s hottest June temperature in nearly a decade since June 29, 2012 (104°).  It would prove to be D.C.’s hottest temperature of the entire summer.  Ironically, this record heat was followed by a record-tying low temperature of 48° at Dulles Airport on June 20 and a record low of 51° at BWI Airport. 

July 2022 turned out to be D.C.’s rainiest month of the year with 7.61” (3.28” above average).  More than half of that occurred on July 9 (4.05”), which was D.C’s fifth wettest July day on record.  More rain fell in the Nation’s Capital on July 9 than in any of the following four months.  August through November were each drier than average and that produced a rainfall deficit of 3.63” in Washington, D.C.  That isn’t a large enough deficit, however, to prevent the Nation’s Capital from finishing with another wetter than average year.  Even if no more rain were to occur this month, D.C. would finish 2022 with 42.06” of annual rainfall.  According to NOAA, Washington, D.C. averages 41.82” of rain in a calendar year. 

Severe Weather: A Rarity in December

 

December 2021 Severe Weather  (Source: NOAA)

Severe weather in December is relatively rare in the United States.  The month of December averages the fewest number of tornadoes of any month with 24, according to NOAA’s National Center for Environmental Information.  Despite this fact, there have been several deadly December severe weather outbreaks in recent years.  “Severe weather” is defined as a thunderstorm that contains any of the following: wind gusts of at least 58 mph, hail 1”/+ in diameter, or a tornado.

2021: A year has passed since December’s deadliest tornado outbreak on record in the United States.  A total of 66 tornadoes touched down on December 10-11, 2021, from Arkansas to Ohio.  This was an especially deadly outbreak since most of the tornadoes occurred at night, including an EF-4 tornado that devastated the town of Dawson Springs, Kentucky.  The state of Kentucky had 80 tornado-related fatalities.  According to NOAA, there were two EF-4 tornadoes and another six EF-3 tornadoes.  Tornado intensity is ranked on the Enhanced Fujita Scale from minimal EF-0 tornadoes with winds of up to 85 mph to an EF-5 with winds over 200 mph.

Several factors contributed to this tornado outbreak.  There was record warmth in the southern Plains states and Tennessee Valley.  That was followed by a powerful area of low pressure which helped create the "lift" in the unstable atmosphere that allowed for the intense, supercell thunderstorms to develop.  A "supercell" thunderstorm is a large, long-lasting thunderstorm that rotates.  A "derecho" brought another 513 severe weather reports across the Upper Midwest on December 15.

2020: A two-day severe weather outbreak on December 23-24 covered a large geographic area with confirmed tornadoes from southeastern Texas to southern Virginia.  Aside from the unusually wide area impacted by this outbreak, several of the tornadoes were quite damaging.  It’s also unusual for the state of Virginia to see tornadic thunderstorms in December.  Fortunately, no fatalities were reported.

2019: Another severe weather outbreak that spanned two days, December 16-17, saw confirmed tornadoes from Louisiana to Georgia.  A total of three fatalities were reported along with several injuries.  Hail 1” – 2” in diameter was also reported in several locations across the Deep South on December 16.    

2018: Over three dozen tornadoes developed and caused extensive damage across the state of Illinois on December 1.  According to the U.S. Storm Prediction Center, the strongest tornado was an EF-3 tornado with winds of 155 mph in Christian County, IL.  Fortunately, there weren’t any reported fatalities during this rare December tornado outbreak.  Based on NOAA data, this was the largest December tornado outbreak in Illinois state history.