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NOAA's Severe Weather Outlook for December 23 |
It would be an understatement to say that NOAA’s December
outlook for above average temperatures across the eastern United States has
come to fruition. Multiple record highs
have been set this month coupled with a lack of snowfall across the eastern two-thirds
of the United States. Many typically
snowy winter cities such as Buffalo and Rochester, NY only recently saw their
first measureable snows of the winter – considerably later than average.
El Nino has recently helped bring the western United
States some much needed rainfall and mountain snows. Meanwhile, many eastern cities – including
Washington, D.C., Baltimore and New York City – are in the midst of one of
their warmest Decembers on record. What’s
helped bring such unusual warmth this month has been the irregular position of
the jet stream. The jet stream – a river
of air in the atmosphere that helps steer guide storms and air masses – has
been uncharacteristically far north over the eastern United States. That’s allowed for the unseasonal warmth on
and off since Halloween – while much of the western U.S. has been cooler and
wetter than average.
Today, there is an area of low pressure in the central
United States that’s going to use this significant temperature gradient – between
colder than average in the western United States and upper Midwest to warmer
than average in the eastern U.S. – to produce a large swath of severe weather
from the Gulf Coast to the Ohio Valley.
Severe weather is rare in December, but not unprecedented.
Although residents of the Mid-Atlantic Region are in
their fourth consecutive warmer than average December – this month is poised to
be the warmest one yet. Through December
22, Washington, D.C. has been more than 8 degrees warmer than average. While warmer than average December weather will
disappoint those wishing for a snowy Christmas, there could be a shift in the
weather pattern to feature more winter-like or at least more seasonal
temperatures. Such was the case the last
two winters when December was warmer than average in the Washington, D.C. –
Baltimore corridor, but January, February and March were all colder than
average.
Washingtonians will be hard-pressed to see
temperatures below freezing the rest of the year. Not only have the last six weeks featured
above average temperatures during the day, but nighttime temperatures have also
been unusually balmy. Although it was 32
degrees once in November in the Nation’s Capital, the first below freezing
temperature didn’t occur downtown until December 19. NOAA’s January outlook calls for at least a
33% chance of above average temperatures to continue in the Mid-Atlantic Region.
Record Highs in
Jeopardy (Degrees Fahrenheit)
December 24:
Washington, D.C. (National Airport): 69 (1933)
Dulles Airport, Sterling, Virginia: 66 (1982)
Baltimore, Maryland (BWI Airport): 65
(1990)
December 25:
Washington, D.C. (National Airport): 72
(1964)
Dulles Airport, Sterling, Virginia: 71
(1982)
Baltimore, Maryland (BWI Airport): 72
(1964)
December 27:
Washington, D.C. (National Airport): 72 (1971)
Dulles Airport, Sterling, Virginia: 73 (1971)
Baltimore, MD (BWI Airport): 65 (1949)