Area Forecast Discussion
Issued by NWS Sterling, VA

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FXUS61 KLWX 161425

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
1025 AM EDT Sun Oct 16 2016

High pressure off the New Jersey coast will shift southward
today and remain to our south through midweek. A cold front may
approach the Mid-Atlantic region late Thursday into Friday.


Quiet weather continues over the Mid-Atlantic courtesy of high
pressure centered off the New Jersey coast. While there was some
early morning low clouds and some patchy dense fog in spots...most
areas are beginning to quickly mix out. For the remainder of
today...while most places will see plenty of sunshine, some
passing mid-level clouds are possible across the northern half of
the area. Highs will be in the lower to mid 70s.


High pressure will be migrating to the south through Tuesday
while 500-surface heights will be rising. 80+ temps do occur in
mid October but it is getting more difficult to achieve. But this
should be done both Monday and Tuesday. With lows in the 50s
tonight and upper 50s/low 60s MOnday night frost/freeze won`t even
have to be considered.


The end of the week and into the weekend will feature a relatively
complex weather pattern. Main players will be a strong but decaying
upper ridge, two upper level shortwaves embedded within a larger
scale trough, and a possible offshore low pressure center. While
some differences still exist with respect to each model`s handling,
there has been a notable trend towards a more progressive and less
impactful solution.

Wednesday should be quite warm and similar to Tuesday with near-
record warmth with highs in the 80s area-wide. A boundary will
approach from the northwest during the day, with models differing on
extent of southeastward progression. At this point will favor ECMWF
depiction, keeping it mainly north of the region. By Thursday,
boundary lifts back northward as a warm front ahead of initial
shortwave energy/surface frontal system moving eastward out of the
Ohio Valley. Thus Thursday likely to be on the warm side again.

Frontal system looks to cross the region in the Thursday
night/Friday time period, with the highest chances of rain showers.
With trend towards greater progression, GFS/ECMWF models now delay
any phasing of initial and trailing shortwaves with possible low
near the coast until they`re far enough north/east to avoid
significant impacts on the region. Thus some drying shown on
Saturday with cooler northwest flow developing. However with
complexity of pattern, will need to monitor for trends.


VFR today through Tuesday outside of the possibility of light
overnight fog at IAD/CHO/MRB.

Mainly VFR expected for Tuesday night through Thursday. May be some
patchy fog/br at night/early morning, mainly MRB/CHO.


Winds expected to remain below SCA values through Monday.

With surface high positioned to the south with warm late-summer-like
air mass, may see development of nocturnal low level jet which could
bring SCA conditions to some of the waters Tuesday night and again
Wednesday night.


Water levels will remain elevated into the beginning of the week due
to full moon/perigean tides. Our more sensitive sites are currently
forecast to reach action stage on several occasions, with minor
flooding possible at DC/Southwest Waterfront.


Unseasonably warm weather more typical of late August is
expected Tuesday and Wednesday. Below is a list of record warm
temperatures for those days (October 18th and 19th).

Washington DC Area (Ronald Reagan National Airport, DCA)
October 18th Record Daily High: 85 (set in 1938 and 1881)
October 18th Record Daily Warm Low: 68 (set in 1947 and 1928)
October 19th Record Daily High: 88 (set in 1938)
October 19th Record Daily Warm Low: 65 (set in 1905)
(Temperature records in the Washington DC area date back to 1872)

Baltimore MD Area (Baltimore-Washington International Thurgood
Marshall Airport, BWI)
October 18th Record Daily High: 82 (set in 1945, 1928 and 1908)
October 18th Record Daily Warm Low: 69 degrees (set in 1928)
October 19th Record Daily High: 82 (set in 1947 and 1908)
October 19th Record Daily Warm Low: 67 (set in 1905)
(Temperature records in the Baltimore MD area date back to 1872)

Washington Dulles International Airport VA (IAD)
October 18th Record Daily High: 82 (set in 2007 and 1963)
October 18th Record Daily Warm Low: 60 (set in 1968)
October 19th Record Daily High: 83 (set in 1991 and 1963)
October 19th Record Daily Warm Low: 60 (set in 2011)
(Temperature records in the Dulles VA area date back to 1962)




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