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Area forecast discussion...updated
National Weather Service Baltimore Maryland/Washington District of Columbia
907 PM EDT Sat Oct 19 2019

the remnants of Nestor will move from southern Georgia Saturday
evening across the Carolinas Sunday, pushing offshore of the
Outer Banks by Sunday evening. A cold front will approach from
the Ohio Valley Monday, then cross the region Tuesday. High
pressure will follow for Wednesday through Friday before another
cold front approaches by Saturday.


Near term /through Sunday/...
00z iad sounding came in very dry below 400 mb this evening and
will take many hours to saturate before rain can reach the
surface. Regional radars show some light echoes across southern
Augusta and Nelson, but obs still show large dewpoint
depressions in excess of 10f degrees. Have lowered pops through
06z tonight and kept them in the chance category. Rain becomes
likely after 06z in the south and after 09z across northeast Maryland.

Previous afd...

Periods of rain will continue to spread across the area from
southwest to northeast Sunday morning, with the heaviest rainfall
expected to fall over southern/eastern Virginia and southern Maryland. The rain
will come to an end around midday or early afternoon on Sunday as
the core remnants of Nestor track off the Outer Banks. Have favored
the higher side of guidance in terms of qpf, painting 0.50-0.75"
along and south of the district, with a half inch or less further
north and west. Up to an inch to an inch and a half will be possible
across portions of central VA, the Northern Neck, and across
southern Maryland. With plentiful cloud cover and elevated rain chances,
temperatures won't budge much from the upper 50s to near 60 degrees
Sunday afternoon.


Short term /Sunday night through Monday night/...

Clouds try to break Sunday night as a drier northerly wind prevails
in the wake of Nestor, which could result in patchy fog across the
area. Lows will bottom out in the 40s to near 50 degrees. High
pressure builds over the area Monday and Monday evening, before
shifting offshore, promoting near normal temperatures and dry
conditions. A cold front will near the Ohio Valley Monday night,
increase shower chances by early Tuesday morning. For now, will
advertise chance pops into the predawn hours Tuesday mainly west of
the Blue Ridge. Lows Monday night will be mild in the 50s.


Long term /Tuesday through Saturday/...
a strong cold front will push across the region Tuesday, bringing
rain showers nearly everywhere. High temperatures should be in the
middle to upper 60s during the day.

There will be a chance for lingering showers Tuesday evening, prior
to a ridge of high pressure building into the region overnight
Tuesday through Wednesday night. Slightly cooler and drier air will
accompany the high. Tuesday night's low temperatures should bottom
out in the upper 40s. Wednesday's high temperatures will be lower to
middle 60s.

The high moves east to and off the East Coast Thursday and Thursday
night. A return flow around the west side of the high will bring
slightly more humid and warmer conditions into the region Thursday
and Thursday night. Highs Thursday could reach the lower 70s with
lows near 50.

On Friday into Friday night, the deterministic models are in
generally good agreement with another cold front approaching from
the northwest. A chance for rain showers late Friday into Friday
night appears to be the flavor. Highs Friday middle to upper 60s
with a possible influence from cloud cover.


Aviation /01z Sunday through Thursday/...
VFR conditions at the terminals through the first half of the night
under a light southerly flow. The remnants of Nestor will near
the Carolinas Sunday morning, bringing periods of rain and low
cigs to the terminals through midday Sunday. MVFR/IFR conditions
forecast during this time frame. Rain exits east of the
terminals Sunday afternoon, however low cigs will persist into
Sunday evening. Drier northerly winds will allow for improving
conditions Sunday night, with patchy fog possible. High pressure
will build over the terminals Monday and Monday evening with
VFR conditions expected. A cold front will approach from the
west late Monday night, bringing the chance for showers to
iad/mrb/cho by daybreak Tuesday, with sub VFR conditions

MVFR conditions Tuesday into Tuesday evening due to rain showers at
the terminals. Winds southeast 5 to 10 knots with higher gusts,
shifting westerly around 10 knots Tuesday night. VFR conditions
Wednesday and Wednesday night. Winds west 5 to 10 knots with higher
gusts Wednesday afternoon, becoming southwest around 5 knots
Wednesday night.


Small Craft Advisory conditions expected to develop over the waters late tonight as
the remnants of Nestor nears the Carolinas and the gradient
increases. Winds will remain near Small Craft Advisory through the day on Sunday,
perhaps nearing gale conditions across the southern Bay and tidal
Potomac waters Sunday afternoon and early evening. Winds will
finally abate late Sunday night into Monday morning as high pressure
builds over the waters through Monday night, with sub Small Craft Advisory conditions

Small craft advisories possible Tuesday night into Wednesday morning
with frontal passage and building high pressure from the west. Winds
southeast 10 to 15 knots Tuesday, shifting west 10 to 15 knots gusts
up to 20 knots Tuesday night into Wednesday morning. Winds mainly
west around 10 knots later Wednesday into Wednesday night.


Tides/coastal flooding...
main only action stages are expected over the next couple of
days. Anomalies remain between half to a foot above normal.


Lwx watches/warnings/advisories...
District of Columbia...none.
Marine...Small Craft Advisory from 10 am to 10 PM EDT Sunday for anz531-
Small Craft Advisory from 1 PM to 6 PM EDT Sunday for anz530-
Small Craft Advisory from 7 am Sunday to midnight EDT Sunday
night for anz532-533-541-542.
Small Craft Advisory from 4 am Sunday to 6 am EDT Monday for
Small Craft Advisory from 10 am to 4 PM EDT Sunday for anz536.


near term...lfr
short term...bkf

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