Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Baltimore Maryland/Washington District of Columbia
938 am EST Friday Nov 28 2014

Synopsis...
high pressure will build in from the west today...then will move
off the coast on Saturday. A warm front is expected to lift to the
north Saturday night. A cold front will then follow on Monday.

&&

Near term /through tonight/...
the upper-level trough is moving off to our east while high
pressure approaches from the Ohio Valley. A few flurries and snow
showers are still occurring due to the cold advection from the
northwest flow. However...any accumulating snow will likely be
confined to locations along and west of the Allegheny Front where
an upslope component to the low-level flow will add to the
coverage of snow showers. Have extended the Winter Weather
Advisory until 1 PM this afternoon for these areas.

Any show showers will quickly end this afternoon as high pressure
builds in from the west. However...it will remain quite chilly
with maximum temperatures ranging from the 20s across the mountains...to the middle 30s
near the Maryland/PA border...to the low 40s in southern Maryland. High pressure
will move overhead tonight leading to dry and calm conditions.
Forecast min temperatures with be in the 20s.

&&

Short term /Saturday through Sunday/...
shortwave in west/northwest middle-level flow looks to stay far enough north to
keep precipitation up in PA Saturday morning. Srefs supports this idea and
thus have a dry forecast. 00z GFS tries to spread a little quantitative precipitation forecast south
of the Mason Dixon line /it would be in the form of snow/ so bears
watching but feel that quantitative precipitation forecast is just a tad too far south from the GFS.

With surface high offshore...warm advection continues through the
weekend. Warm front looks to lift to the north Saturday night or
early Sunday morning. In the wake of its passage maxima likely are
able to rise into the middle to upper 50s for much of the County Warning Area.
Southeast portions of the County Warning Area should see some sunshine but clouds
are likely to be stubborn across the northwest County Warning Area and there will
also be a chance of rain showers.

&&

Long term /Sunday night through Thursday/...
above normal temperatures continue on Monday...likely a few degrees
higher over Sunday/S maxima. There will be a cold front approaching
in the morning...moving through in the afternoon and evening.
Moisture is not impressive...nevertheless there will be low probability of precipitation in
the forecast for rain showers most especially out west toward the
Potomac Highlands.

Front winds up in the Carolinas on Tuesday as high pressure builds
in from the north. Colder air moves in for Tuesday. Front may also
be quick to return north as a warm front Tuesday night into
Wednesday bringing a chance of precipitation again.

&&

Aviation /15z Friday through Tuesday/...
VFR conditions are expected today and tonight. Northwest flow will
continue today. Northwest winds will gust around 20 knots through this
afternoon. High pressure moves overhead tonight and winds will
become southerly by Sat morning.

High pressure builds in for Friday then moves offshore for the
weekend. No significant weather is expected. A cold front will move
through later Monday.

&&

Marine...
northwest flow will continue on the waters through this afternoon.
A Small Craft Advisory remains in effect for all of the waters
today. High pressure moves overhead tonight and winds will become
SW-S by Sat morning

Southerly winds may get close to Small Craft Advisory criteria up the Chesapeake Bay
later Saturday afternoon but confidence too low to issue Small Craft Advisory at this time.
Seems more likely Saturday evening into the night. Cold front moves
through late Monday...possibly a northerly surge may promote Small Craft Advisory
conditions Monday night.

&&

Lwx watches/warnings/advisories...
District of Columbia...none.
Maryland...Winter Weather Advisory until 1 PM EST this afternoon for
mdz501.
Virginia...Winter Weather Advisory until 1 PM EST this afternoon for
vaz503.
WV...Winter Weather Advisory until 1 PM EST this afternoon for
wvz501-503-505.
Marine...Small Craft Advisory until 6 PM EST this evening for
anz530>543.

&&

$$
Synopsis...bpp/has
near term...bjl/has
short term...bpp
long term...bpp
aviation...bjl/bpp/has
marine...bjl/bpp/has

National Weather Service Glossary of Abbreviations