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Posted at 10:27 AM ET, 01/03/2013

Washington, D.C. in longest recorded drought without 2 inch or greater snow event


January 26, 2011 — Snow falls in Northwest D.C. 5 inches was officially recorded at National Airport. The region has not received at least 2 inches of snow since that storm. (Ian Livingston)
Though Christmas week was a wintry one for some of Washington, D.C.’s north and west suburbs, the city failed to record any significant snowfall. Through today, only 0.2 inches of snow has officially fallen this winter.

It’s been almost two years since Washington’s last “real” snow event - the so-called “Commutageddon” storm of January 26, 2011 - when 5 inches blanketed the city. Yes, we’ve seen a *little* snow since then, but nothing proving more than a nuisance, if that.

We now have a running stretch of 708 days without a 2 inch or greater snowfall, the longest span on record dating back to the late 1800s.

Let’s start with how rare it is to get a winter without a two inch snowfall event.


2 inch snowfall events by season at Washington, D.C. (Ian Livingston)
Only six winters since official snow records (1888-89) began have seen no 2 inch or greater snowfall events. Five of those winters have come since the 1970s — most recently last winter. On the other extreme, we’ve seen two seasons with eight such events (1891-92 and 1904-05).

D.C.’s most recent season with a high number of 2 inch or greater snowfall events was the very snowy one of 1995-96. It featured six snow events of this size. The other abundantly snowy and record-breaking seasons of 2002-03 and 2009-10 both had five such events.

A linear trend suggests D.C. had about an average of four 2 inch snowfall events early in the historical period. That has trended downward to just over two now. Looking at only the period of National Airport (mid-1940s through now), the linear trend falls from a high of just over three per winter to a current of around two and a half per season.

To put the current 708 day streak without a 2 inch storm into some perspective, I looked at the stretch between 2 inch snowfall events (not counting the days these “bookend” events began or ended) for the 10 seasons prior to our current streak.


Time between the final 2 inch snow event of the season prior and the first of the season noted, as recorded at DCA. (Ian Livingston)

Our average number of days with no 2 inch or greater snows was 331 days, or roughly 11 months.

The longest stretch in that 10-season period was 451 days. This happened between the December 5, 2007 “coincidence” snowstorm, that dropped 2.6 inches of snow, and the one which hit the area March 1-2, 2009 dropping around half a foot.

Previous record stretches with snow droughts of this sort have ranged from 661-699 days.

The former top spot, running 699 days, was bookended by storms of this nature on February 4-5, 1975 (4.2 inches) and January 5, 1977 (2.3 inches). During that snow drought, eight events dropped 3.9 inches of snow.

This current snow drought, which began January 27, 2011 has seen eight events dropping a total of 3.5 inches of snow. If you really want to feel the snow drought, consider that 4 inches of snow fell from 8 p.m. through 11 p.m. on February 5, 2010.

D.C.’s largest snowfall during this current streak of futility occurred in early 2012, when 1.1 inches fell surrounding midnight January 20-21, 2012.


In addition to these top five streaks, one ending 12/18/1919 ran 614 days. *As of and including January 3, 2013. Each day forward thru the one prior to the next 2” snowfall will count toward this total. (Ian Livingston)

Overall, the event average for this nearly two-year stretch is only about 0.4 inches. Barely more than a dusting, as any snow loving resident will attest to.

Though this historical analysis focuses on National Airport, where debates often rage about its accuracy for the region as a whole, the lowlands throughout the D.C. area are in a similar snow drought.

Dulles Airport has not received a 2 inch snowfall during this time either. There have been three events of just over 1 inch there, out of 12 events total — dropping 7.4 inches of snow — following the January 26, 2011 storm.

BWI received a 2 inch or greater snowstorm a month after (February 22, 2011) the last in D.C. and at Dulles in . This was a small system that featured rain changing to snow across the area. BWI managed to get into one of the strongest snow bands, and picked up 2.5 inches

Given the records at D.C., the stretch of 681 days without a 2 inch or greater event at BWI is also quite likely a record or imminently headed there.

Snow lovers might take some relief knowing D.C.’s December average snowfall of just 2.3 inches suggests it’s not necessarily the month to be looking for such events. With over 80 percent of our average snow still to come, there’s at least a good shot we’ll be tracking a potential 2 inch or greater event moving ahead.

Hat tip to MN Transplant on AmericanWx.com for pointing out the recent stretch as a record.

By  |  10:27 AM ET, 01/03/2013

Categories:  Local Climate, Capital Weather Gang, Latest

 
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