Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wakefield Virginia
1247 am EST Friday Nov 28 2014
low pressure continues to push farther offshore overnight.
High pressure builds into the area through Saturday. The high
becomes centered off the southeast coast Sunday into Monday as low
pressure tracks across the Great Lakes.
Near term /until 6 am this morning/...
surface low pressure continues to move away from the CST overnight...while surface hi
pressure from the middle MS valley begins to build over the mountains into the
mdatlc region. Earlier rain showers have dissipated...residual moisture has
been slo to break in vicinity of southeast Virginia/NE NC past few hours. Expecting clearing for
those areas overnight...W/ mainly sky clear elsewhere. The clouds have been holding
temperatures up over southeast Virginia/NE NC...but that likely to change soon. Low
temperatures ranging from the M/u20s west of I 95 to the l/m30s southeast.
Short term /6 am this morning through Sunday/...
a quiet period expected...although temperatures will remain well
below normal on Friday even under nearly full sunshine. This will
result from strong high pressure centered over the Tennessee Valley...building
east into the Carolinas. Northwest winds averaging 10-15 miles per hour in the
morning will generally become lighter by afternoon as the pressure gradient
weakens. Blended guidance looks reasonable for highs given 850 mb
temperatures prognosticated to be -8 to -10 c. This will yield highs mainly in
the lower 40s throughout...middle 40s in NE NC and it may not get out
of the upper 30s across the far north. Thankfully...the sun will
finally shine. NAM/GFS/ECMWF in good agreement with a broad upper
level ridge over the Southern Plains by Friday night...allowing the upper flow
to flatten over the eastern Continental U.S.. this brings an increase in middle
level cloudiness late Friday/Friday night...particularly across the north.
Still expect a cold night...as temperatures rapidly drop in the
evening then level off thereafter. Lows mainly 25-30 f...not
really any warmer near the coast due to light flow on the northern
side of the surface high. Skies average partly to mostly cloudy
north...and partly sunny south on Sat...with decreasing clouds in
the afternoon. Temperatures moderate a bit on Sat as low level flow shifts to
the south-southwest. Still a bit below average with highs 50-55 f central and
south and in the upper 40s north.
Long term /Sunday night through Thursday/...
an active northern stream will send a couple of fast moving cold
fronts through the Middle Atlantic States during the long term period.
Ridging along the latitude of the Gulf of Mexico and Florida will
keep heights high enough to limit the southward penetration of
A cold front will cross the local area on Monday. Moisture will be
limited with the frontal passage. Middle level moisture following the
front may produce periods of light rain Monday night through
Wednesday with 20 to 30 percent probability of precipitation. The next cold front moves
through Wednesday. The front moves off the coast with a clearing sky
from the west but slight chance probability of precipitation continuing toward the coast through
Temperatures average near to slightly above normal during the long
term. Highs in the upper 50s NE to middle 60s SW Monday cool to the middle
40s northwest to middle 50s southeast Tuesday. Highs in the 50s are forecast
Wednesday and Thursday. Lows in the 40s Monday morning lower to the
upper 30s to middle 40s Tuesday through Thursday mornings.
Aviation /06z Friday through Tuesday/...
hi pressure will build over the area during today...resulting in VFR
conditions persisting at the taf sites. Expect just hi clouds and
maybe some middle level clouds this eveng through Sat...as a weak warm
front aloft lifts into and across the area. Northwest winds will gust to
near 20 knots late this morning...as cold air advection continues across the region.
Outlook...mainly VFR conditions with south-southwest winds are expected Sat
night into Monday...as hi pressure will be off the middle Atlantic/southeast CST.
low pressure has located off the eastern NC coast this afternoon as
strong ~1034mb surface high pressure builds over the Midwest. Northerly flow
over the waters this afternoon average 10-15 knots. Seas average 3-5
feet...highest in the northern coastal zones. Strengthening pressure
gradient in tandem with cold air advection will result in Small Craft Advisory conditions over the
waters tonight into Friday morning. Strongest cold air advection arrives this evening
into the overnight...with northwesterly winds increasing to 20-25 knots with
gusts up to 30 knots over the Bay/sound/coastal waters. 15-20 knots with
gusts to 25 knots over the eastern Virginia rivers. Seas build to 4-6 feet with
waves 3-4 feet. High pressure builds over the waters Friday morning as
cold air advection wanes and northwesterly winds subside. Headlines run through middle morning for
the rivers and early afternoon for the Bay. Seas remain 4-5 feet through
the day...with headlines extended through 6pm Friday. Thereafter...high
pressure and sub-Small Craft Advisory conditions prevail through the weekend. The next
cold front crosses the waters Monday-Monday evening. High pressure then
builds over New England Monday night-tues...ridging over central Virginia.
Resultant north-NE flow will increase to near Small Craft Advisory conditions Monday
night-Tuesday as seas build to 4-5 feet. The next cold front is forecast
to cross the waters Wednesday night into Thursday.
Marine...Small Craft Advisory until 10 am EST this morning for
Small Craft Advisory until 1 PM EST this afternoon for
Small Craft Advisory until 6 PM EST this evening for anz650-