Centreville, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

061
FXUS61 KLWX 231857
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
157 PM EST Sat Nov 23 2024

.SYNOPSIS...
High pressure briefly returns Sunday before another front
pushes through Monday into Tuesday. A more potent front and low
pressure system look to arrive for the Thanksgiving holiday
period.

&&

.NEAR TERM /THROUGH TONIGHT/...
Upslope shower activity across the Alleghenies will slowly
decrease through the evening as the upper level low exits off
the northern New England coast. Most of the precipitation has
transitioned to rain as of 130 PM, but a few flakes or patchy
areas of freezing drizzle are possible across the highest
elevations. Breezy conditions will remain through the evening as
the pressure gradient remains tight. This will result in
continued wind gusts of 20-35 mph (up to 45 mph along the higher
ridges).

Lows tonight will fall back into the mid to upper 30s for most,
with 20s in the mountains.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
High pressure briefly returns Sunday before moving off the
southeast U.S Monday. This will bring dry conditions along with
moderating temperatures. Highs Sunday will push into the low to
mid 50s with 40s over the mountains. Lows Sunday night will
fall into 30s.

Dry conditions will continue through the first half of Monday.
An area of low pressure and it`s associated cold front are
expected to cross the region late Monday into early Tuesday.
Guidance continues to show rain showers overspreading the
Alleghenies Monday evening with the showers spreading east
overnight. Light QPF amounts are expected with this system,
generally a tenth of an inch or less aside form the Alleghenies.

The moderating trend continues on Monday with temperatures in
the upper 50s to near 60 for most. Mostly sunny skies to start
will give way to mostly cloudy skies by the late afternoon/evening
ahead of the approaching low. Lows only fall into the 40s to
near 50 for most Monday night.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
If it hasn`t already, the cold front will be pushing east of the
area Tuesday morning, with any shower chances quickly ending. An
exception may be the upslope areas in the Alleghenies, where a brief
changeover to snow could occur before precipitation ends around
midday. Gusty west winds will follow the front, but the downsloping
flow will allow high temperatures to reach the lower 60s again in
some of the piedmont and coastal areas.

A fairly flat upper level pattern will result in an area of high
pressure moving overhead by Wednesday morning and quickly moving off
to the east Wednesday night. Temperatures are forecast to be
slightly below normal during this time.

The next shortwave will quickly approach from the Rockies by early
Thursday, with surface low pressure eventually strengthening toward
the east coast. While precipitation is looking increasingly likely
at some point between late Wednesday night and Friday morning, there
remain some uncertainties with the track of the low and associated
thermal profiles. Any sort of wintry weather looks to be most likely
confined to the Allegheny and Potomac Highlands, although there are
non-zero probabilities across much of the climo-favored areas
northwest of I-95. Thanksgiving will likely be chilly and rainy for
much of the area either way.

As long as the system stays progressive, Friday and Saturday are
forecast to dry out east of the mountains with a gusty northwest
wind and temperatures trending further below normal. Meanwhile,
accumulating upslope snow will commence west of the Allegheny Front.
Confidence remains low on amounts this far out.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
VFR conditions are expected to continue at most terminals
through Monday. Brief periods of MVFR cigs are possible through
this evening as the upper level low slowly exits the region.

Wind will remain the main hazard today due to the tight
gradient overhead. Expect sustained west to northwest winds at
10-20 kts with gusts of 20-30 kts through this evening. West to
northwest winds will decrease tonight into Sunday with gusts
15-20 kts.

Potential for sub-VFR conditions arrive Monday night into
Tuesday as another low pressure system crosses the region. A few
showers will accompany the low and it`s associated front
leading to to some cig/vsby restrictions at times. Winds will
turn to the south Monday at 5-15 kts. Winds increase late Monday
night into Tuesday as the front passes.

After frontal passage Tuesday morning, west winds will gust 20-30 kt
until sunset. No significant weather is forecast Tuesday night and
Wednesday with high pressure. The next low pressure system will
arrive by Thanksgiving with rain and sub-VFR conditions.

&&

.MARINE...
High end SCA conditions with gusts between 25 to 30 kts out of
the west/northwest are expected over all waters through early
Sunday morning. Have extended SCAs through midday Sunday across
the the Chesapeake where winds are slow to taper. Sub-SCA level
winds are expected late Sunday afternoon through Monday as high
pressure builds nearby.

Winds become southerly Monday as high pressure moves offshore.
Southerly channeling may develop across the wider waters of the
Chesapeake resulting in SCAs. A cold front may bring a line of
gusty showers across the waters late Monday night into Tuesday
morning. SCAs are most likely, but could see a few gusts near
gale force.

After a cold front crosses Tuesday morning, winds will turn to the
west and gust 20-30 kt through the day. While winds will gradually
decrease Tuesday night into Wednesday morning, advisory conditions
will likely linger along the bay. High pressure will bring lighter
winds on Wednesday. The next low pressure system will approach
Thursday, but its track and strength remain uncertain at this
time.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Small Craft Advisory until 1 PM EST Sunday for MDZ008.
VA...None.
WV...None.
MARINE...Small Craft Advisory until 1 PM EST Sunday for ANZ530>534-
     538>543.
     Small Craft Advisory until 7 AM EST Sunday for ANZ535>537.

&&

$$

SYNOPSIS...EST
NEAR TERM...CPB
SHORT TERM...CPB
LONG TERM...ADS
AVIATION...ADS/CPB
MARINE...ADS/CPB