Chesapeake, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

111
FXUS61 KAKQ 211525
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
1025 AM EST Thu Nov 21 2024

.SYNOPSIS...
Low pressure will push offshore of the Delmarva coast early this
morning. Meanwhile, several disturbances drop across the area
over the next couple of days, bringing a prolonged period of
gusty winds and chilly temperatures. Weak high pressure builds
over the area late in the weekend, bringing a gradual warmup for
the first half of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 1025 AM EST Thursday...

Key Messages...

-  Blustery and much cooler weather conditions behind a strong
   cold front. NW winds average 15-20 mph with gusts to 25 to
   30 mph (highest coastal areas).

-  Remaining mainly dry, aside from a few showers over the
   northern neck and the eastern shore.

-  A Freeze Watch has been issued for Thursday night over
   interior northeast NC and portions of the western Tidewater
   area.

Latest analysis reveals a potent upper level low centered over
the Great Lakes at sunrise this morning. At the surface, a
strong ~996mb sfc low was analyzed over the upper peninsula of
Michigan, with a secondary low now just offshore of the NJ coast.

The strong trough and its associated sfc low will pivot SSE into
the northern mid-Atlantic through tonight, with the sfc low near
New York City becoming the primary sfc low tonight, as it
retrogrades west into SE NY towards the wobbling upper low.
There will be multiple shortwaves transversing SE along the
trough, thereby allowing multiple reinforcing shots of cooler
air. The first (and weakest) of these shortwaves push through
this afternoon and this evening. This allows the area to start
drying out today on breezy WNW winds. Another surge of gusty
winds to 20 to 30 mph are expected, along with some sct mid-
level clouds by afternoon and perhaps a few showers (or
sprinkles) this evening along the eastern shore. Otherwise,
expect most of the area to remain dry through tonight. Highs
only top out in the low to mid 50s.

Winds do decouple a bit inland later tonight, which will make
for a stark temperature contrast between inland areas and the
coast. Look for lows in the upper 20s to low 30s inland, with
mid to upper 30s along the coast. This will put a narrow stripe
of counties still active in the frost-freeze program at lows
right around freezing. Have gone ahead and added these counties
from Bertie/Northampton and Gates NC up to James City in a
Freeze Watch for tonight. Either way, look for wind chills in
the 20s for most of the area overnight.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
As of 645 AM EST Thursday...

Key Messages...

- Another disturbance dropping across the region will provide
  another day of gusty winds, and increasing clouds for Friday.

- More widespread showers are possible on Friday. A few
  instances of graupel or even some wet snowflakes are possible
  over northern portions of the area Friday morning into early
  afternoon.

The Sfc low over E PA dives back SE tomorrow, and with the upper
low diving into the northern mid-Atlantic, this will send the
second shortwave through the region Friday. This feature looks
to be a bit stronger, providing a stronger shot of CAA with
highs in the mid upper 40s across the Piedmont and lower 50s
along the SE coast. Have increased PoPs into likely range for
the northern neck and eastern shore for showers from midday
Friday into Friday night. Have also included some low end PoPs
for along and to the S of the I-64 corridor into RIC metro and
Hampton Roads. Given the relatively shallow moisture layer
between 850-700 mb farther south, would expect minimal QPF.
However, that moisture layer is mostly within the DGZ and could
easily result in a few reports of graupel or even a few
snowflakes mixing in over northern portions of the area Friday
morning into the early afternoon. Ground temperatures would be
much too warm for any impacts, but certainly a sharp contrast
from just a few days ago.

Drying out Friday evening/night, but remaining breezy and partly
to mostly cloudy early with partial clearing late. Early
morning low temperatures not quite as cold in the upper 30s and
lower 40s.

The upper level trough will begin to move out of the area into
the Gulf of Maine Saturday, as upper ridging builds to the east.
This will allow a milder day with highs warming back into the
middle 50s to around 60. The breezy conditions gradually relax
late Saturday into Sunday as the trough moves out of the region.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
As of 410 AM EST Thursday...

Key Messages...

-  High pressure moves back in bringing dry weather back across the
region over the weekend into early next week.

Temperatures next week are expected gradually moderate each day
through midweek, as the high moves off the coast and upper
ridging crests overhead Monday and Tuesday. Highs warming back
into the upper 50s to around 60s on Monday, with highs in the
lower 60s by midweek. Early morning lows warm back into the 40s
Tuesday and Wednesday mornings.

Rain chances return to the forecast next Wednesday ahead of the
next system arriving from the NW. Will note, by the middle of
next week the ensembles do disagree with the placement and
strength of the next system. However, they do agree on a
potential system and Pops remain tn the forecast and stay
between 15-25%.

The surface low slowly shifts into the Gulf of Main on Saturday
afternoon and night.

&&

.AVIATION /16Z THURSDAY THROUGH MONDAY/...
As of 645 AM EST Thursday...

The well-advertised strong cold front swept across the region
earlier this morning, bringing gusty winds, showers and variable
CIGs to area terminals. Conditions continue to gradually improve
in the wake of the front, and CIGs have returned to VFR across
area terminals. Expect the VFR CIGs persist through the period,
with NW winds to average 10-15 kt w/gusts to around 25 kt from
late morning through early evening. Sct aftn CU/Stratocu clouds
are expected, but CIGs should remain VFR, averaging 6-8 Kft
AGL.

Outlook: Additional upper disturbances pinwheeling through will
maintain gusty W-NW winds Fri- Sat. Winds will gust to 25-30 KT
on Friday, before gradually diminishing Saturday into Sunday.
Scattered to numerous showers and flight restrictions are expected
across N/NE sections of the area (KSBY) Friday aftn/Fri night.

&&

.MARINE...
As of 700 AM EST Thursday...

Key Messages:

- Small Craft Advisories are in effect for all local waters
  through Friday afternoon.

- Gale Watches have been issued for all local waters from late
  Friday afternoon through Friday night.

Early morning surface analysis depicted a cold front E of the local
waters with an occluded low over the Great Lakes and a secondary low
off the Mid Atlantic coast. Winds were NW 20-25 kt with gusts
up to 30 kt across the Ches Bay, coastal waters, and Lower
James River. As such, Gale Warnings have been replaced with
SCAs. Winds gradually diminish this morning as the pressure
gradient weakens, eventually becoming W this afternoon. A period
of potentially sub-SCA conditions is possible across the upper
rivers and Currituck Sound later this morning into this
afternoon with W winds 15-20 kt with gusts up to 25 kt across
the Ches Bay and southern coastal waters. However, W winds
increase back to 20-25 kt with gusts up to 30 kt late this
afternoon into tonight behind a secondary cold front. A few
gusts up to 35 kt are possible across the coastal waters and
lower bay with this surge, however, wind probs for gusts of 34
kt are <40% (lower for zonal averages). Additionally, the surge
looks to be brief (~3 hrs). As such, will refrain from issuing
Gale Warnings for this surge at this time.

Winds remain elevated (although trending lower) into Fri before a
trough moves through, reinforcing the CAA yet again. Wind probs for
34 kt gusts are high for this surge with probs approaching 100%
across the coastal waters and 70% across the Ches Bay. As such,
expect W winds to increase to 25-30 kt with gusts up to 40 kt across
all local waters late Fri afternoon through Fri night.
Therefore, Gale Watches have been issued for late Fri afternoon
through Fri night. SCA conditions continue Sat before winds
gradually diminish Sat night into Sun as high pressure builds
in.

Waves and seas of 3-5 ft and 4-7 ft (locally higher across the
NC coastal waters) respectively continue to be possible early
this morning. Waves subside to 2-4 ft later this morning with
seas remaining elevated into Sat night. Another period of 4-5 ft
waves is possible with the Fri afternoon into night surge.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...Freeze Watch from late tonight through Friday morning for
     NCZ012>014-030.
VA...Freeze Watch from late tonight through Friday morning for
     VAZ089-090-092-093-096.
MARINE...Small Craft Advisory until 4 PM EST Friday for ANZ630>638-650-
     652-654-656-658.
     Gale Watch from Friday afternoon through Saturday morning for
     ANZ630>634-638-650-652-654-656-658.
     Gale Watch from Friday afternoon through late Friday night for
     ANZ635>637.

&&

$$

SYNOPSIS...MAM
NEAR TERM...HET/MAM
SHORT TERM...HET/MAM
LONG TERM...HET/MAM
AVIATION...LKB/MAM
MARINE...RMM