Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wakefield Virginia
1004 PM EDT Thursday Aug 27 2015
high pressure will reside over the region through the weekend.
Near term /until 6 am Friday morning/...
isolated showers are still lingering offshore and also along the
Albemarle Sound late this evening. Have maintained minimal probability of precipitation
(20%) for the next few hours before precipitation expected to dissipate.
Otw...surface high pressure slowly builds across the area from the northwest
overnight. Mostly clear to partly cloudy north and west to mostly cloudy
across the southeast. Lows from near 60 northwest to near 70 immediate coast.
Short term /6 am Friday morning through Sunday/...
short term period starts off Friday with surface hi pressure centering over
the middle Atlantic region. This will allow for dry weather with a mostly sunny
sky and low humidity. Temperatures will be near normal for late Aug...with
highs avgg in the middle 80s. The hi slides offshore Friday night into Sat
with upper-level energy staying north of the forecast area and dry weather continuing.
After Erly morng lows ranging through the 60s...temperatures will maximum out in
the middle/upper 80s Sat afternoon. Slight warming trend continues into sun
with highs near 90 in many spots as southerly flow develops. Included a
slight chance of a rain showers/thunderstorm sun as some moisture and shortwave energy
aloft approach from the SW. Not expecting anything too widespread
at this time hence the low probability of precipitation.
Long term /Sunday night through Thursday/...
the longwave pattern next week appears to be characterized by broad
middle/upper ridging from the north-central to northestern US...with a weak trough
in vicinity of the Gulf Coast. Broad east-southeast flow beneath the ridge is
expected to bring increasing tropical moisture into the southeastern US.
Whether this is in the form of a plume of tropical moisture or some
form of ts Erika is highly uncertain at this time. Nonetheless...the
general model consensus is to keep deep moisture suppressed S of the
middle-Atlantic region. Given this...only diurnal probability of precipitation are
forecast...primarily across the southern Virginia/NE NC and in the 20-30%
range. Warm and increasingly humid next week with forecast highs in
the upper 80s to low 90s...with middle 80s at the immediate coast.
Forecast lows are in the upper 60s to low 70s.
Aviation /02z Friday through Tuesday/...
high pressure continues building into the region from the
northwest...with VFR conds expected through Friday. Middle clouds are currently
restricted to NE NC...and those are expected to gradually erode
overnight. Light north/NE winds overnight...will gradually turn out of
the southeast on Friday at kric/sby but remain below 10 kts.
Surface high pressure remains in control near/just North/East of the middle
Atlantic region through the weekend...with generally dry/VFR conditions
prevailing (could see some patchy early am fog Sat/sun).
Small Craft Advisory has been canceled...as seas have fallen to
around 4 feet...and not expected to increase significantly
overnight. High pressure over the Great Lakes combined with weak
low pressure off the southeast coast is helping to drive a 15 knots
NE wind off the coast of the Currituck Outer Banks. Seas are
elevated to around 4 feet in the NE NC coastal waters...and should
remain that way into early Friday. Elsewhere wind speeds are
generally around 10 knots out of the N-NE. The wind is expected to
diminish slightly this evening...but the gradient is expected to
tighten some tonight as high pressure slowly nudges eastward and low
pressure remains nearly stationary. Seas are expected to average
3-4ft north of the Virginia/NC border tonight...with 1 to 2 feet waves in the
Bay...rivers and sound. Could be an isolated 3 foot wave near the
mouth of the Bay throuh 06z...but should mainly be 1-2 feet.
Otherwise...high pressure becomes established near or slightly off
the middle Atlantic coast through early next week. The wind will
generally fluctuate from NE-southeast trough the weekend...and then trend
southerly early next week...with speeds averaging at or below 10-15kt.
Seas should average 2-3 feet through the weekend into early next
week...with 1-2 feet waves.