Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wakefield Virginia
534 PM EDT Wednesday Oct 22 2014
low pressure will intensify while slowly tracking northeast off
the middle Atlantic coast through Friday. Unsettled conditions will
prevail into tonight...followed by drier conditions and a warming
trend Thursday and Friday.
Near term /until 6 am Thursday morning/...
latest msas analysis shows 1005 mb surface low about 100 miles east of the
Maryland Eastern Shore...with a stacked upper low following suit and
tracking slow NE just offshore. Best instability remains offshore this
afternoon in vicinity of the low pressure area...where some thunderstorm
activity is still ongoing. Elsewhere...wrap around moisture
continues to bring light rain/drizzle southward along the I-95
corridor...though this activity has trended weaker in the past few
hours. Still seeing some breaks in the clouds across our SW
zones...where temperatures were able to warm into the middle 60s. Low
pressure will continue to deepen and shift NE through tonight...
locating off the New Jersey coast by 12z Thursday. Will keep high probability of precipitation across
our eastern zones into this evening as the wrap around precipitation
continues to drop south. Precipitation should continue to trend lighter
along the I-95 corridor...with light rain becoming just
drizzle/sprinkles before ending after sunset. By late evening and
overnight...remaining chance probability of precipitation will be limited to far eastern Virginia
and especially the Eastern Shore. Clouds will continue to decrease
across the SW...with sky conditions becoming partly to mostly
clear overnight. Mostly cloudy elsewhere. Remaining breezy to
windy along the coast...especially NE sections. Lows in the low 40s
west to around 50 at the coast.
Short term /6 am Thursday morning through Saturday/...
low pressure tracks quickly NE off the New England coast Thursday
and Friday. Meanwhile...high pressure will gradually build in from
the Ohio Valley. Pressure gradient remains tight between these two
features Thursday...allowing breezy/windy conditions to continue.
Highest winds will be along the coast where gusts of 30-35 miles per hour
will occur...15-25 miles per hour elsewhere. A 20% pop will be maintained for
the Eastern Shore...dry elsewhere. Still enough residual low level
moisture and a cold pool aloft for skies to average out mostly cloudy
NE to partly to mostly sunny SW. Highs in the upper 50s/around 60
on the Maryland Eastern Shore...to the upper 60s for interior NE NC and
south central Virginia. Mostly clear SW to partly cloudy NE Thursday night
with lows in the 40s to lower 50s. Low pressure moves farther NE
and away from the local area on Friday allowing for mainly sunny
conds...diminishing winds...and milder temperatures. Highs Friday in the
middle 60s NE to around 70 f SW. High pressure remains in control
Saturday for dry and pleasant conditions. Highs in the upper 60s to
Long term /Saturday night through Wednesday/...
a weak trough clips the northern middle-Atlantic Saturday night and quickly
moves off the coast Sunday. A high amplitude middle/upper level ridge
builds over the eastern US Monday and Tuesday...with the axis shifting
offshore by Wednesday. Given this...dry conditions will prevail
through Wednesday. High temperatures should average in the upper 60s
to around 70 Sunday...and trend upward into the low/middle 70s by
Monday through Wednesday. Lows through the period should average
from the low/middle 40s northwest...to the low/middle 50s for southeast coastal
locations. A cold front approaches from the northwest later in the period.
22/12z GFS/European model (ecmwf) each have trended somewhat wetter as a wave of low
pressure develops along the front. However...moisture appears to be
Aviation /22z Wednesday through Monday/...
surface low pressure will continue to deepen offshore and slowly
shift to the NE through the 18z taf period. Mostly MVFR ceilings
will prevail as moisture pulled from the south is wrapped around the
storm and into the mid-Atlantic. Due to the added moisture and upper
level support...scattered pockets of rain/showers will last through
the evening...ending the latest over the Eastern Shore. With that
being said...there is evidence of drier air being pulled into the
system over south central Virginia with ceilings ~5k feet. Expect this
drier air to make its way east as the system moves farther offshore.
Winds will remain elevated overnight(~15-20kt) and Thursday
aftn(~20-25kt) as the pressure gradient remains strong between the
departing low and a surface high approaching from the west.
VFR conditions are expected tonight/Thursday morning through the weekend
as high pressure makes its way over the Ohio River valley and into the
Tennessee River valley.
low pressure continues to intensify off the middle Atlantic coast this
afternoon. A north-northwest wind should continue to increase over the next few
hours and average 25-30kt...with gusts to around 40kt through the
evening (20-25kt...with gusts to around 30kt over the rivers). Seas
should build to 6-9ft north through S out near 20nm...with 4-6ft seas
nearshore...and 3-5ft waves in the Bay. The low begins to slowly
lift NE late tonight and reaches a position off of Cape Cod Thursday
afternoon/Friday evening. Wind speeds gradually diminish through
this time...but should remain within Small Craft Advisory criteria. The gradient
finally slackens enough for Small Craft Advisory conditions to subside Friday night.
Another boundary crosses the region Saturday night bringing the
potential for another period of Small Craft Advisory conditions. High pressure
eventually builds over the area Monday through Wednesday.
tidal departures in vicinity of Ocean City Inlet will average
around 1.5ft above normal during high tide this evening and
Thursday morning. The current forecast has Ocean City Inlet
falling just below minor thresholds this evening and exceeding
minor during high tide Thursday morning as the astronomical tide
will be a few tenths higher. With a north-northwest wind...the main areas of
concern will be along the shorelines of Assawoman and chincoteauge
bays...and the adjacent ocean inlets.
Marine...Small Craft Advisory until 5 am EDT Friday for anz635>638.
Gale Warning until 1 PM EDT Thursday for anz630>632-634-656-
Gale Warning until 1 am EDT Thursday for anz633.
Gale Warning until 5 PM EDT Thursday for anz650-652-654.