Weather Quiz

Prior to last month and this month, when was the last time Washingtonians experienced a December and January that were both at least two degrees warmer than average?

A.  December 1997 – January 1998

B.  December 2001 – January 2002

C.  December 2006 – January 2007

D.  December 2012 – January 2013

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Answer to Weather Quiz question from January 16.

True.  This January is on track to be DC’s warmest since 2006.

Winter is Here. Now What?

It’s with some irony that parts of the DC Metro Region had light snow this morning as January comes to a close.  That’s because this winter has had little snow to this point, with an official total of only 1.4” at National Airport.  Through January 29, this month’s average temperature of 42.4 degrees is 6.4 degrees warmer than average in Washington, D.C.  That would make this January the warmest in DC since 2006 (43.1 degrees). 

Contributing to making this month so warm is an impressive record streak of 18 consecutive days when temperatures remained above freezing.  High temperatures reached the 50s on eight different days this month, while temperatures fell below freezing on only six occasions.  The high temperature of 72 degrees on January 12 was DC’s warmest day since mid-November. 

On the opposite end of the spectrum was the brief round of very cold weather early this month.  From January 6 – 8, high temperatures in the Nation’s Capital remained in the 20s for the coldest January stretch since 2014.  Had it not been for this period of unusual cold, this month would have ranked higher on the list of warmest Januarys in the Nation’s Capital.  Still, given the current average monthly temperature of 42.4 degrees, January 2017 will rank as the twelve warmest on record according to National Weather Service data. 

Some perceive this month as being rather dreary since measurable precipitation occurred on 13 days with another seven days seeing a trace of precipitation.  None of it was especially heavy, with the wettest day being January 3 when 0.86” fell at National Airport.  The monthly total of 2.75” is very close to the monthly average of 2.81”.

Conditions at Dulles Airport have been similar with an average monthly temperature of 39.8 degrees through January 29.  This could be Dulles’ warmest January in more than a decade.  Dulles Airport saw a record high of 70 degrees on January 12, in addition to five days that either tied or set new record high-low temperatures.  Having such warm overnight temperatures were a key contributor to making this month so much warmer than average.  This morning’s light snow helped bring Dulles Airport’s monthly snowfall total to 1” compared to January’s average of 7.3”.

The combination of a significantly warmer than average January, following the sixth consecutive warmer than average December in Washington, D.C., puts the 2016-2017 winter season in a strong position to finish warmer than average.  Meteorological winter is the three-month period of December, January and February.  NOAA’s temperature outlook for February calls for a cooler than average start to the month and near average temperatures for the entire month in this part of the country.

Ranking This January

NOAA's Temperature Outlook for early February

Since January 1, Washington, D.C. has been 6.6 degrees warmer than average.  This January is well-positioned to finish significantly warmer than average for the first time since 2013.  That’s despite having the coldest three-day January stretch since 2014 earlier this month.

Area residents remember that the last few winters have featured more snow than the average annual 15.4” in the Nation’s Capital.  However, only six days this month were below freezing in Washington, D.C.  According to the Capital Climate blog, Washingtonians have had 11 days this month where temperatures didn’t fall below 40 degrees – the third highest total on record.  Today has also set a new record with 17 consecutive January days above freezing in Washington, D.C.

Although no record highs have were set downtown this month, two record high-low temperatures were set at National Airport.  The warmest temperature this month in Washington, D.C. was 72 degrees on January 12.  With such mild weather for the bulk of the month, there has been only 0.4” of snow in the Nation’s Capital.  That total would be January’s smallest since 2006 when only a trace was observed (too little to measure).  Washingtonians average 5.6” of snow in January, but saw 18.8” of snow last January.  Meanwhile, 13 of the last 20 Januarys have featured below average snowfall in the Nation’s Capital.

Snow lovers shouldn’t fret, though, since February and early March can sometimes feature significant amounts of snow in the Mid-Atlantic Region.  In 2003, Washingtonians experienced a storm over President’s Day weekend that brought 16.4” of snow downtown with much higher totals west and north of the city.  March 2014 was the snowiest March in the Nation’s Capital since 1960 when 12.7” was observed at National Airport.

The statistics at Dulles Airport have been similar to National Airport as January temperatures were seven degrees warmer than average through January 26.  One record high temperature was set at Dulles this month, along with three record high-low temperatures that were either tied or broken.  Dulles Airport had only 0.7” of snow this month or roughly 10% of their January average.  While this winter has seen little snow and cold weather, NOAA expects some colder than average weather over the next two weeks.  And appreciable snow can still occur well into the month of March as Washingtonians have seen in recent years.

January Severe Weather is Rare and Deadly

NOAA's Severe Weather Outlook (1-22-17)

The atmospheric ingredients required for severe weather are most common during the spring and summer months.  Although isolated cases of severe weather aren’t uncommon in January, the large-scale contrast between differing air masses that facilitate large severe weather outbreaks are rare.  NOAA dates indicates that the month of January averages 35 tornadoes – the third fewest of any month.  That’s what makes the current severe weather outbreak across the southeastern U.S. both historic and tragic.

2017:  More than 500 reports of severe weather, including more than six dozen tornadoes, have occurred across the southeastern U.S. during the last four days (January 19 – 22).  Unfortunately, some of these tornadoes caused fatalities and that underscores the importance of staying informed.  Some at-risk communities don’t have a tornado siren, so a good investment for your family would be a NOAA weather radio that can alert you to looming danger – day or night.  Nationally, 44 tornadoes have already occurred this month, which is more than double the 18 that occurred in January 2016.  There have also been 18 tornado-related fatalities so far this month – more than the 17 than occurred in the United States during all of last year.

2013: Another severe weather outbreak occurred on January 29-30, 2013.  There was a combined total of more than 800 severe weather reports – including wind gusts over 58 mph, hail 1” in diameter or greater, and tornadoes.  Unlike the severe weather outbreak of the last few days, this severe weather occurred primarily across the Tennessee Valley and Mid-Atlantic Region.

2008: Another rare January severe weather outbreak happened on January 7 – 11, 2008 and featured over 300 severe weather reports.  Roughly a third were tornadoes.  This round of severe weather caused five fatalities during the five-day period.  This severe weather struck from the Midwest to the East Coast.  The scope of this severe weather was unusual since the Midwest is usually in the deep freeze in January.

2006: Of the nearly 200 severe reports that occurred on January 2, 2006, from Illinois to Florida, 18 of them were tornadoes.  The severe weather on this day was impressive for the amount of geography it covered from the Great Lakes region to the Gulf Coast.