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Area forecast discussion 
National Weather Service Wakefield Virginia
330 am EDT Wed Oct 26 2016

high pressure remains over the region today. A cold front
approaches from the northwest Thursday afternoon and crosses the
area during the evening. High pressure returns Friday.


Near term /through tonight/...
we're off to a cool start this morning thanks to Canadian high
pressure situated over the northern Great Lakes. Temps have
dropped into the mid/upr 30s across portion of the lower Maryland
Eastern Shore and also interior portions of central/eastern
Virginia. We continue to see some high clouds streaming into the
region, basically following the I-64 corridor from cho to ric to
orf. These clouds are not allowing temps to drop to their lowest
potential and so therefore any frost this morning will remain
patchy across central/eastern Virginia. On the Eastern Shore, temps are
a couple of degree cooler with a clear sky and a better likelihood
of widespread frost. Therefore, will continue with a frost
advisory through 9am.

Continued cool today under a partly to mostly sunny sky. 850mb
temperatures moderate to +3 NE to +7 SW. However, this will be
offset by the combination of high pressure over the region and
low-level NE flow, which will limit mixing. Forecast highs are in
the mid/upper 50s NE to low 60s SW. The surface high gradually
pushes offshore tonight as low pressure tracks toward the Great
Lakes. The surface ridge axis remains near the coast much of the
night, so lows will still be cool under a mostly clear to partly
cloudy sky ranging from the upper 30s over the lower Maryland ern shore
to the low 40s elsewhere.


Short term /Thursday through Friday/...
shortwave energy will lift through the Great Lakes tonight into
Thursday, with the trailing cold front approaching from the NW
Thursday aftn and crossing the area Thursday evening. Clouds
increase early Thursday with much of the area becoming mostly
cloudy to overcast. Chc pops (25-40%) for showers spread across
the nrn half of the area by afternoon. The better potential for
showers will be with the front Thursday evening, with 40-55% pops
from the nrn neck to the ern shore, and 20-30% elsewhere. Moisture
is limited with this system, so current quantitative precipitation forecast through 12z Friday is
aob 0.15". Highs Thursday range from the mid 60s NW to near 70

The front pushes offshore late Thursday night into early Friday
morning with high pressure returning by aftn. Clouds are expected
to decrease Friday with most of the area becoming mostly sunny by
late morning and aftn. Lows in the upper 40s to mid 50s Friday
morning will be followed by highs in the low 60s to around 70.


Long term /Friday night through Tuesday/...
surface high pressure slides south of the region Saturday, centering
along the southeast coast. Shortwave ridging aloft builds over the
eastern US. The result will be deep layer southwest to west flow and
warming temperatures. 850mb temperatures warm to around 12-14c (+1
Standard deviation) Saturday. Have trended temperatures warmer, with
highs generally in the low to mid 70's. Cooler Eastern Shore. Medium
range guidance now in better agreement with pushing a northern
stream shortwave across the northeast states Sunday. A dry cold
front is progged to drop into the region Sunday afternoon into
Sunday evening, but not before temperatures warm into the mid
(possibly upper) 70's. Trough axis pushes offshore Sunday night
along with the dry cold front. Upper/surface high pressure returns
to the region Monday. Highs in the mi to upper 60's. Heights begin
to build again across the southeast and mid-Atlantic as upper level
high pressure over the Gulf of Mexico builds northward. The result
will be another warming trend with highs back into the upper 60's to
low 70's Tuesday. Mild overnight temperatures expected through the
period, with lows generally in the upper 40's to low/mid 50's. The
exception will be Saturday night, when lows are in the mid to upper


Aviation /06z Wednesday through Sunday/...
a ridge of high pressure extending south from Canada into the mid
Atlantic states will dominate over the mid Atlantic states through
the 06z taf period. This ridge will shift slowly toward the coast
by late Wednesday. Light winds will prevail through the period.

Outlook...high pressure slides off the coast late Wednesday night
into Thursday morning and there could be some patchy fog as low-
level moisture increases. A low pressure system moving from the
Midwest to the northeast states will drag a cold front through the
region Thursday evening. High pressure returns Friday and Saturday
and settles off the coast as another cold front approaches from the
west on Sunday.


no headlines expected in short term as the cold air advection surge is weakening
across the southern waters. High pressure across southern Canada
builds south today resulting a north-NE wind below 15 kts. Waves 1-2 ft
with 2-3 ft seas.

High pressure pushes offshore tonight ahead of the next cold front.
Gradient tightens Thursday resulting in south to southeast winds
increasing to between 15-20 knots late Thursday. Waves build to 2-3
feet and seas 3-5 feet. The cold front pushes across the waters late
Thursday night with yet another cold air advection surge behind it (nw 15-25 kts).
Waves 2-4 feet and seas 3-5 feet. Decided to hold off on and Small Craft Advisory
headlines for now given this is mainly a 4th and 5th period event.

High pressure returns to the waters late Friday through Sat. A cold
front crosses the waters late in the weekend into early next week.


Akq watches/warnings/advisories...
Maryland...frost advisory until 9 am EDT this morning for mdz021>024.


near term...jdm
short term...ajz/jdm
long term...Sam

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