Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wakefield Virginia
827 PM EST Sat Mar 8 2014
a cold front crosses the area late tonight. High pressure builds
into the middle Atlantic region Sunday through Tuesday. Low pressure
approaches from the southwest Tuesday night then tracks across the
middle Atlantic region Wednesday.
Near term /until 6 am Sunday morning/...
cold front prognosticated to cross the area late tonight then move offshore
Sunday morning. Models show best moisture / forcing north of forecast area but
appears enough energy lags far enough south to continue the low chance probability of precipitation
across Eastern Shore / Northern Neck areas. Clouds & a lght west wind expeceted
to keep temperatures above freezing so that any precipitation that does fall late
tonight will be in liquid form. Lows M-u30s north...l40s south.
Short term /6 am Sunday morning through Tuesday night/...
high pressure builds back into the region behind the departing cold
front Sunday and then across the Gulf Coast states Monday & Tuesday.
Expect a brief cool down Sunday due to a north wind & lower 850 mb temperatures.
Highs u40s-l50s near the water...m50s-l60s west of the Bay.
Clear skies Sun night allows for decent radiational cooling. Lows in
the 30s. Pt to mostly sunny skies along with a SW wind Monday and Tuesday.
This allows for a dry and Spring like period. Highs Monday 60-65 Eastern
Shore...65-70 west of the Bay. Lows Monday night in the 40s. Highs Tuesday
M-u60s Eastern Shore...u60s-l70s west of Bay.
Long term /Wednesday through Saturday/...
GFS and European model (ecmwf) are coming into better agreement handling the
strong storm system forecast to track across the middle Atlantic
Wednesday. The GFS tracks the low across the area about 6 hours faster
than the European model (ecmwf). Either way there will be a good chance for showers
and even the possibility of a few thunderstorms
Wednesday...especially in the afternoon...as the storm system
tracks from Kentucky across Virginia. Models agree the storm system will
deepen rapidly Wednesday afternoon. Going with a model blend have
increased probability of precipitation to likely for Wednesday with the best chance for showers
and storms in the afternoon. Conditions will become windy with
gusty south to southwesterly winds developing as the system deepens. Lows Wednesday
morning will be rather mild in the middle to upper 40s with highs Wednesday
afternoon in the middle 50s to middle 60s. Afternoon highs Wednesday will
depend on the exact timing of the storm system and when winds
become northwest ushering in cooler temperatures. The storm system will be
rapidly departing the Delaware-Maryland-Virginia Wednesday evening/night. Behind the
system strong northwesterly winds drive a surge of cold air across Virginia and
down into the Carolinas. 1000-850 mb thicknesses fall 100 meters
from 18z Wednesday to 18z Thursday. Lows Wednesday night drop back into the low 30s
with highs Thursday struggling into the low to middle 40s. The coldest
nigh of the week will be Thursday night as high pressure settles
in and lows drop into the middle to upper 20s. This cold snap should
be rather short lived as temperatures slowly start to rebound
Friday into the 50s and even 60s possible for next weekend.
Aviation /02z Sunday through Thursday/...
as of 01z...a cold front across southeast Pennsylvania to middle
Tennessee will move south through the taf sites early Sunday
morning. The front should be dry for the most part but a few showers
are possible at sby and have vcsh there from 10-13z. Winds shift to
north/northwest behind the front and may be gusty at times Sunday morning.
Outlook...VFR conditions Sunday night through Tuesday. Another cold
front moves into the Middle Atlantic States Wednesday as low pressure
intensifies over the Mississippi Valley. The low moves quickly
across the region Wednesday and off the coast Wednesday night.
Expect a period of showers with areas of IFR Wednesday and Wednesday
night. Showers end by Thursday.
as of 8 PM...Small Craft Advisory remains for the coastal waters through 10 PM where
seas have subsided to between 5 and 6 feet. May need to extend the
Small Craft Advisory a bit longer and will decide before 10 PM.
From previous discussion..
a dry cold front will push south across the Bay and coastal
waters Sunday morning with enough of a cold air surge to increase
winds to 15 knots on the Bay and 15 to 20 knots over the coastal waters
north of Cape Charles. Will keep conditions below Small Craft Advisory for the
entire area though seas will build in the northwest winds. Calmer
conditions return late Sunday through Monday and Tuesday as a weak
high pressure builds in from the SW. Winds become S to SW Sunday
night and remain out of the SW well below Small Craft Advisory conditions through
Tuesday. SW winds increase Wednesday as strong low pressure move out of Kentucky
tracking towards the Delaware-Maryland-Virginia. SW winds will likely increase to
Small Craft Advisory Wednesday afternoon as surface pressures fall rapidly with the
deepening storm system. As the system pulls off the coast Wednesday
night and Thursday expect northwest winds and a strong cold air surge to
continue Small Craft Advisory conditions Wednesday night and most of the day Thursday. Winds
will decrease late Thursday night and Friday as high pressure builds in. Seas
along the coast will likely remain above Small Craft Advisory late next week even
after winds subside due to a NE swell.
Marine...Small Craft Advisory until 10 PM EST this evening for anz650-