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Area forecast discussion...updated 
National Weather Service Baltimore Maryland/Washington District of Columbia
917 PM EST Sat Nov 28 2015

a slow moving cold front will move through the area overnight and
move into the Carolinas Sunday and Monday. High pressure builds
over New England Monday then moves offshore Tuesday. Another cold
front will pass through the area Wednesday. High pressure is
expected to move into the area for the end of the week.


Near term /through Sunday/...
front is currently moving through the north central Maryland counties
where winds have shifted to a northerly direction. Overnight...
we'll see front continue to push south with rounds of light rain
affecting the area. Ensemble guidance shows definite rain with
amounts between 0.10 and o.25 inches affecting most if not all of
the forecast area.

Front pushes into northern NC Sunday morning with light rain persisting
around the Charlottesville area. Clouds will hold over much of the
forecast area xcpt over northeastern Maryland where some breaks appear
likely. However...this will be short lived as jet cirrus
overspread the area again tomorrow night.


Short term /Sunday night through 6 PM Sunday/...
at the surface...the cold front will cross the region from north to
south this evening and winds will become northerly but light. Cold air advection
will slowly move into the region as high pressure builds in from the
north. Forecast min temperatures will range from the low to middle 40s in the
north and to the low to middle 50s. Cloudy conditions will slowly
improve from north to south Sunday as dry air moves in aloft.
Temperatures will not move much Sunday with high temperatures in the middle to
upper 40s.


Long term /Sunday night through Saturday/...
boundary is not going to be able to make it very far to the
high pressure over southern Quebec will be tracking to the east...not to the S.
It is hard to pinpoint the exact location where clouds will
transition from overcast to pc...clouds may show clearing across northern Maryland...or in
southern PA. Probability of precipitation will remain relegated to the southern 1/3 of the forecast area.
Where there are precipitation chances temperatures will remain warm euf that the p-type
would be a cold rain - u30s/a40.

Models implying somewhat of a cad situation setting up for Monday as
the high to the north moves offshore and a wedge of high pressure develops on
the east side of the aplchns. Oftentimes middle Atlantic will remain cloudy and dry
in this pattern. During first half of the day will have low probability of precipitation in the
S...W/ some increases during the afternoon. Highs in the u40s/a50.

As the high moves away Monday night/Tuesday this will allow the fnt to move
back north as a warm fnt. Probability of precipitation will continue to increases to the likely Cat for
Monday night and Tuesday. Temperatures continue to remain above freezing Monday night...and m50s

Warm front should be north of County Warning Area by 00z Wednesday...with
weak southerly return flow across the area...which will increase low-
/mid-level moisture and hold temperatures nearly steady in the M/u40s
overnight. Most guidance continues to indicate periods of showery
activity continuing through frontal passage. Current forecast has
front near I-95 corridor Wednesday morning...and east of our area by
Wednesday evening. Some guidance is hinting at upslope precipitation
in the far west late Wednesday into Thursday morning...and with
temperatures rapidly falling below freezing...there could be a few
snow showers.

Cooler and drier air will filter in behind the front for the
remainder of the week as high pressure builds into the area from the


Aviation /02z Sunday through Thursday/...
MVFR conditions expected overnight through 15z sun in light rain.
Pushed back the onset of MVFR conditions to after 06z as onset of
lower ceilings and visibilities have been slow to occur. MVFR conditions will
last longer at kcho and may persist all of Sun night.

Near overcast conds at all taf sites Sun night and Monday...possibly in the
MVFR range...and then continued degradation Monday night and Tuesday as a
warm fnt pushes back into the middle Atlantic.

Sub-VFR conditions will likely continue Tuesday night into
Wednesday morning and remain until frontal passage during the day

VFR conditions expected the remainder of the workweek.


a cold front will slowly cross the waters tonight and winds will
become nearly. A surge of higher winds will move down the Main
Channel of the Chesapeake Bay Sun night into Monday. At this
time...gusts should stay below 18kts but will need to be

Gusts to Small Craft Advisory levels possible during Monday on the ches Bay.

Small Craft Advisory conditions possible in the cold air advection in the wake of frontal passage
Wednesday afternoon/evening. Strongest surge likely occurs
Thursday...with greatest chance for Small Craft Advisory then. Winds should drop below
Small Craft Advisory by late Thursday as high pressure builds overhead.


Lwx watches/warnings/advisories...
District of Columbia...none.


near term...lfr
short term...lfr
long term...abw

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