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Area forecast discussion 
National Weather Service Baltimore Maryland/Washington District of Columbia
151 PM EDT Thursday Aug 28 2014

Synopsis...
a cold front will continue to drift south from central Virginia into
the evening. High pressure will shift across the northern
middle-Atlantic tonight into Friday...anchoring off the coast into the
weekend. A warm front will lift north through the area late
Saturday. An active pattern is then expected Sunday through the
middle of next week.

&&

Near term /through Friday/...
as of 17z...weak Ana-cold front still extends from central Virginia to NC
and is drifting south. An associated cumulus field is across
Charlottesville and south. Expect north/northwest winds gusting up
to 18 miles per hour rest of this afternoon.

High pressure over the Great Lakes shifts east-southeast across the
northern middle-Atlantic tonight into Friday morning before heading to
Bermuda through the weekend. Northerly flow will become northeasterly Friday
morning and become onshore Friday night. Fog should be limited as
dry air settles in. Near normal temperatures through Saturday as a result
of the high pressure passage.

&&

Short term /Friday night through Sunday/...
this weekend high pressure heads out to sea Saturday with return
flow aided by low pressure over the Great Lakes. A warm front moves
through the County Warning Area late Saturday with low chance probability of precipitation west of I-95. Positive vorticity advection
ahead of the Great Lakes trough brings likely probability of precipitation Piedmont and west
(high chances east) for Sunday. Gulf moisture plume of 2 inch precipitable waters
and any lingering boundaries or training storms would cause flood
concerns. Increased quantitative precipitation forecast for now. Later shifts will need to
consider wording in the severe weather potential statement.

&&

Long term /Sunday night through Thursday/...
southerly flow will continue across the middle Atlantic as high
pressure stays anchored to the east. Flow aloft will become southwesterly as
the subtropical ridge moves off the southeast coast. Disturbances are
expected to move in the SW flow aloft resulting in the chance of
showers and thunderstorms Sunday night. A Lee trough will likely
set up as well leading to a mechanism to initiate convection. This
setup will continue through the start of the work week. A cold front
is prognosticated to move through the region Tuesday evening. Showers and
thunderstorms expected in the vicinity of the front. High pressure
and will move into the region Wednesday night and Thursday leading
to dry conditions and temperatures near normal.

&&

Aviation /18z Thursday through Tuesday/...
northwesterly/northerly flow gusting up to 18 knots will continue through the
afternoon. VFR into Saturday as high pressure over the Great Lakes
moves across the northern middle-Atlantic tonight and offshore Friday.
Onshore flow Friday night...becoming southerly Saturday night. Warm front
with chances for thunderstorms Saturday...then an upper level
disturbance Sunday with greater coverage and potentially heavy
thunderstorms. Daily chances for thunderstorms next week as the
hot/humid pattern continues.



&&

Marine...
gusty northwesterly/northerly flow rest of the afternoon. Gusts mainly 15-17kt with
some stray 18-19kt gusts possible. However...the pressure gradient
is slacking...so a Small Craft Advisory is not anticipated as of
this time.

Northerly flow tonight as high pressure pushes east across the northern
mid-Atlantic...then onshore tomorrow through Saturday as high
pressure remains offshore. Southerly return flow Saturday night after a
warm front. Scattered thunderstorms Sunday. Daily chances for
thunderstorms next week as the hot/humid pattern continues.

&&

Lwx watches/warnings/advisories...
District of Columbia...none.
Maryland...none.
Virginia...none.
WV...none.
Marine...none.

&&

$$
Synopsis...baj
near term...baj
short term...baj
long term...cem
aviation...baj
marine...baj

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