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fxus61 kakq 171031 

Area forecast discussion
National Weather Service Wakefield Virginia
631 am EDT Thu Oct 17 2019

a gusty northwest wind Thursday in the wake of a cold front
passage. High pressure builds into the area for the end of the
week resulting in cool and dry weather. A disturbance in the
Gulf may bring showers to the area late in the weekend.


Near term /through tonight/...
as of 400 am EDT Thursday...

Cold front cleared the area last evening, and skies have cleared
out across the region. Strengthening low across the northeast
and high pressure building in behind the front is resulting in a
tight pressure gradient across the area. West/northwest winds are gusting
20-30mph near the coast in Maryland and Virginia and 15-20mph further inland.
Cooler air continues to filter in, low temps this morning will be in
the lower 40s generally west of I-95 and mid to upper 40s across the
eastern half of the forecast area. Strongest winds will be this
afternoon into the early evening hours, generally 20-30mph gusts
however some gusts around 45mph are expected across the Maryland
Eastern Shore (and into Accomack co va) where a Wind Advisory
has been issued for today.


Short term /Friday through Saturday night/...
as of 400 am EDT Thursday...

The pressure gradient will relax late Thursday into Friday
morning, and winds should subside to 5-10mph by 12z Friday. High
pressure centered over the Ohio Valley will remain in control
for Friday and Saturday. Temps will remain cool with high temps
in the 60s, and low temps ranging from the upper 30s to mid 40s
along the coast. A few locations across the western portions of
the area may drop into the mid 30s Saturday morning. Winds will
be nearly calm and with clear skies expected, would not be
surprised to see some reports of frost Saturday morning.


Long term /Sunday through Wednesday/...
as of 400 am EDT Thursday...

Our next chance for rain will likely come from a disturbance
currently in the western Gulf. Models are in better agreement
that this system will ride up the southeast coast this weekend
and will be in our vicinity beginning late Saturday night into
Sunday morning and likely bring showers to our forecast area
during the day on Sunday. Both the latest runs of the GFS and
European model (ecmwf) have precip exiting the area by late Sunday and keeping
Monday dry. Lowered pops for Monday but did not completely
remove them as confidence that far out is still on the lower
side. Trended cooler with the temps on Sunday, as rainfall and
cloud cover should hold Max temps into the 60s. Assuming precip
does exit the region by Sunday night, temps rebound to the low
to mid 70s on Monday ahead of an approaching cold front. The cold
front will cross the region on Tuesday bringing another round
of showers and then cooler and drier conditions for Wednesday.
Low temps on Wednesday will be in the upper 40s to lower 50s and
high temps on Wednesday will struggle to reach 70.


Aviation /12z Thursday through Monday/...
as of 630 am EDT Thursday...

VFR conditions through the taf period. Gusty west/northwest winds through
the period due to a tightening pressure gradient from a
strengthening low in the northeast and high pressure to the
west. Wind gusts will be 20-25kts throughout the day with gusts
to around 35kts at ksby. Winds will decrease to 10-15kts late
Thursday night into Friday morning as the pressure gradient

VFR conditions through at least Saturday. A storm system
currently in the western Gulf is forecast to make it's way up
the southeast coast this weekend...bringing the threat of
showers to our area for Sunday.


as of 430 am EDT Thursday...

Strong west winds prevail across the waters as intense sfc low
pressure (~975mb) is moving NE along the New England coast while
sfc high pressure is building into the lower MS valley. Decided
to extend the Gale Warning in the Northern Bay through this
evening even though conditions have dropped a little below gale
thresholds for the moment. High res models suggest some deeper
mixing may bring a return of slightly higher winds this
aftn/early evening as wind slowly veer from the west to the northwest.
Gales remain in effect into early Fri am for the coastal water
north of Cape Charles Light. Small Craft Advisory is in place elsewhere for winds
mainly 20-25kt with gusts to 30 kt. Seas are mainly 5-7 ft with
Bay waves 3-5 ft. The current forecast has winds remaining aoa
Small Craft Advisory thresholds for Bay and coast through ~12-15z Fri. Sub-Small Craft Advisory
conditions return by late Fri, as high pressure settles over the
waters. Latest GFS/European model (ecmwf) models have trended into better
agreement with the approach of another low pressure system from
the south-southwest Sat night, pushing off the mid-Atlantic coast on Sunday.
Did not go as high with waves/seas/winds as some of the model
guidance but did increase winds to 15-20 kt over much of the
area with seas building to 5-6 ft Sunday and waves to 3-4 ft at
the mouth of the Bay. And late this weekend before exiting to
the NE early next week. Thus, another round of scas (starting by
sunday) looks likely now for at least the coastal waters and
Lower Bay.


Tides/coastal flooding...
as of 430 am EDT Thursday...

Water levels at bishop's head and Cambridge, Maryland crested right
at major flood thresholds yesterday and have rapidly dropped off
given the strong west flow and Ebb tide dominance that will
continue today/tonight. No additional coastal flooding with
subsequent high tide cycles through Sat. While the water levels
have dropped, they are not expected to get down so far that any
low water advisories would be needed.


Akq watches/warnings/advisories...
Maryland...Wind Advisory until 8 PM EDT this evening for mdz021>025.
Virginia...Wind Advisory until 8 PM EDT this evening for vaz099.
Marine...Small Craft Advisory until 10 am EDT Friday for anz631>638-656-
Gale Warning until 10 PM EDT this evening for anz630.
Gale Warning until 1 am EDT Friday for anz650-652-654.


near term...cmf
short term...cmf

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