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Area forecast discussion 
National Weather Service Baltimore Maryland/Washington District of Columbia
354 am EDT Wednesday Oct 7 2015


High pressure will build into the middle-Atlantic region today. A
cold front will cross the area Friday...slowly pushing south
through the area Saturday morning. High pressure is expected to
return to the region Saturday afternoon through Monday. A cold
front may move into the Middle Atlantic States Tuesday.


Near term /today/...

As of 07z...surface high pressure is over the eastern half of the
Continental U.S....centered at 1024mb over northern Maryland...under a broad upper trough
stretching along the Canada/US border east from Minnesota. Another upper
trough is off the southeastern coast...trailing the remnant low that was
over the southeastern states this past week. Just some wispy cirrus over
much of the area with some middle-level clouds over northwestern fourth of the
County Warning Area. Fog is limited for now despite the calm and dewpoint now in the
50s. Cloud cover is expected to increase rest of the night should
limit fog development.

Today...weak shortwave trough embedded in the broad upper trough
crosses the area from the west. Middle-level clouds persist over the
area into the late afternoon before clearing from the north.
Isolated showers possible (and featured in the past few hrrr runs)
in vicinity of August County. Tranquil or light north breeze...maximum temperatures
similar to yesterday...middle to upper 70s (80f possible for sunniest


Short term /tonight through Thursday/...

Partly cloudy with continued calm. Min temperatures low to middle 50s.
Thursday...another shortwave trough approaches from the west
during the day. Isolated showers possible again over southwestern zones.
Maximum temperatures generally middle 70s.


Long term /Thursday night through Tuesday/...

Cold fnt is expeceted to be developing over Ohio Thursday night...reaching the
aplchns Friday during middle/late afternoon Friday...then the Eastern Shore Friday evening.
It looks lake the fnt will be lagging over the area Sat. High pressure
should build back into the middle Atlantic Sat night and sun.

Temperatures Friday should warm to the mu70s.

In terms of sensible weather...the weather/probability of precipitation we have been forecasting look good -
likely in the far west Friday afternoon/chance in the east. Guidance sdng profiles are
still indicating that skinny cape can be expeceted. Hodographs are not
impressive. Prvs shift added low chance of thunder to the grids east of
the mountains Friday afternoon/evening which seems plausible. Storm Prediction Center has placed much
of the County Warning Area in a marginal risk for severe...which is line west/ what the
sref severe product is showing. But given skinny cape/weak shear this
will not be mentioned in the severe weather potential statement.

Skies will be slow to clear Sat...and have extend the chance of rain shower into
midday Sat west/ the slow moving fnt.

Sunday looks to be the better weather day of the weekend. M sunny skies west/
highs u60s/a70. Monday also looking good west/ highs in the lm70s.


Aviation /07z Wednesday through Sunday/...

Calm rest of the night with increasing middle-level clouds limiting
fog. Isolated showers in vicinity of kcho this afternoon from a weak upper
disturbance. Elsewhere VFR ceilings and light northerly flow. Calm again
tonight with continued VFR.

In the extend...clouds will be on the increases Thursday night ahead of an aprchg cold
fnt. Sub VFR conds will be possible Friday afternoon/night as the fnt aprchs...
bringing the cwc of rain shower/isolated thunderstorm. Conds will be slow to
improve...and it may not be until Sat afternoon that



Light northerly flow then through tonight...shifting Ely Thursday but
remaining light.

Biggest concern in the extend will be the cold fnt aprchg the waters Friday
evening. Small Craft Advisory level winds will be possible on srly winds ahead of the fnt....and
then behind the fnt during 1st half of Sat. Isolated thunderstorms will be possible
Friday evening which may have the potential to produce smw-level winds.

No probs expeceted Sat night through Monday.


Tides/coastal flooding...

Positive tidal anomalies continue to slowly decrease through
tonight. Morning/afternoon high tide is lesser...but will approach
minor levels for Calvert/Anne Arundel and DC/Alexandria. As of now
only confidence in minor for St Marys at Straits Point. Minor
coastal flooding possible again tonight for the preferred high
tide...but would need to overcome the decreasing anomalies.


Lwx watches/warnings/advisories...
District of Columbia...coastal Flood Advisory until 7 am EDT this morning for dcz001.
Maryland...coastal Flood Advisory until 7 am EDT this morning for mdz014-
Coastal Flood Advisory until 5 am EDT early this morning for
Coastal Flood Advisory until 2 PM EDT this afternoon for
Virginia...coastal Flood Advisory until 7 am EDT this morning for vaz054.
Marine...coastal Flood Advisory until 7 am EDT this morning for anz535.
Coastal Flood Advisory until 5 am EDT early this morning for



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