136
FXUS61 KLWX 170034
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
834 PM EDT Fri Oct 16 2026

.WHAT HAS CHANGED...
Cancelled severe thunderstorm watch early areawide. Expanded
Freeze Watch to central Maryland and western Loudoun.

&&

.KEY MESSAGES...
- 1) Strong cold front moves through this evening.

- 2) Frost and/or freezing temperatures are possible this
  weekend.

- 3) Nor`easter to develop off the Carolina coast late in the
  weekend lingers much of next week.

&&

.DISCUSSION...
KEY MESSAGE 1...Strong cold front moves through this evening.

Strong cold front moving through southern Maryland as of 0030Z
Oct 17. Some rain developing on the backside with gradient winds
picking up. Nothing hazardous in terms of rain or wind aside
from over the waters. Forecast remains on track tonight.

KEY MESSAGE 2...Frost and/or freezing temperatures are possible
this weekend.

Given very favorable setup for radiational cooling, expanded
Freeze Watch to central MD and western Loudoun where
probabilities for near 32F exist. Previous discussion follows...

Strong cold advection will ensue within northwesterly flow
behind the cold front tonight through the day tomorrow. Upslope
showers in the Alleghenies may even end as a few flakes of snow
late tonight, but no accumulation is expected. Temperatures are
forecast to drop into the 40s by daybreak tomorrow (mid- upper
30s mountains). A few showers could linger from Central Virginia
to Southern Maryland tomorrow morning, but gradual clearing is
expected tomorrow afternoon as the upper trough axis progresses
to our east and large scale subsidence starts to increase.
Temperatures will be much cooler tomorrow, with highs in the 50s
(40s mountains).

High pressure will gradually build in from the west tomorrow
night as a nor`easter simultaneously starts to develop off the
Carolina coastline. The main question tomorrow night is which
locations will decouple. The setup for radiational cooling will
be nearly ideal in locations that go calm, with clear skies
expected and dewpoints in the 20s. Temperatures will likely
plummet into the 20s and lower 30s where winds go calm.
Confidence is currently the highest for winds going calm to the
west of the Blue Ridge, with greater uncertainty with respect to
the winds further east as the nor`easter develops offshore. A
Freeze Watch has been issued to the west of the Blue Ridge,
where confidence is highest for sub-freezing temperatures. Some
frost or sub-freezing temperatures can`t be ruled out further
east, either. Forecast confidence decreases further moving into
Sunday. Forecast models show considerable spread with respect
to the location of the aforementioned nor`easter during that
time period. Some solutions keep the system offshore, while
others have it retrograding further westward, which could lead
to impacts locally.

KEY MESSAGE 3...Nor`easter to develop off the Carolina coast late
in the weekend lingers much of next week.

Part of the upper trough that swings through tonight into
Saturday will cutoff along the front stalling to the south later
this weekend. This result in the development of a nor`easter
off the Carolina coast. This system then meanders offshore/near
the coast, but guidance varies widely on its placement and
strength. Since it will be cut off from the main steering flow,
it could persist much of next week. Northeast breezes and
occasional rain chances are possible, with the highest chances
further east.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
Winds shift to out of the northwest and pick up behind the
front this evening. North to northwesterly winds will then gust
to around 20 to 30 knots through the day tomorrow. Other then a
potential brief period of MVFR ceilings at CHO late tonight, VFR
conditions are expected tonight through this weekend. Winds
this weekend will be out of the north to northeast as a coastal
low develops offshore.

Some rain or sub-VFR could develop Mon-Tue with a nor`easter lurking
offshore, especially for areas further east. NE winds could become
breezy at times depending on how close the system gets.

&&

.MARINE...
Winds then shift to out of the northwest behind the front
tonight, with SCA gusts continuing. Gale Warnings go into effect
to the south of the Bay Bridge tomorrow and continue tomorrow
night. SCAs remain in effect elsewhere through tomorrow night.
After that, attention turns to a nor`easter that is forecast to
develop offshore. SCA conditions likely continue through the day
Sunday in northeasterly flow, but forecast uncertainty during
that time period remains high.

NE winds around a nor`easter to the south may remain gusty much of
next week. In fact, gales are possible at times over the
wider/southern waters.

&&

.TIDES/COASTAL FLOODING...
Annapolis remain under a Coastal Flood Advisory through the
tide cycle this evening.

Water levels are forecast to rapidly decrease within
northwesterly flow behind a strong cold front tonight into
Saturday. Water levels may rapidly rise again on Sunday as a
coastal low develops offshore and winds turn to more out of the
northeast.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Small Craft Advisory until 6 AM EDT Sunday for MDZ008.
     Freeze Watch from late Saturday night through Sunday morning
     for MDZ003>006-501-502-507-509-510.
     Coastal Flood Advisory until 11 PM EDT this evening for MDZ014.
VA...Freeze Watch from late Saturday night through Sunday morning
     for VAZ025>031-503>505-507-508.
WV...Freeze Watch from late Saturday night through Sunday morning
     for WVZ050>053-055-501>506.
MARINE...Small Craft Advisory until 6 AM EDT Sunday for ANZ530-531-
     538>542.
     Small Craft Advisory until 6 AM EDT Saturday for ANZ532>534-
     537-543.
     Gale Warning from 6 AM Saturday to 6 AM EDT Sunday for
     ANZ532>534-537-543.
     Small Craft Advisory until 11 PM EDT Saturday for ANZ535-536.

&&

$$

DISCUSSION...DHOF/KJP/CPB
AVIATION...DHOF/KJP/CPB
MARINE...DHOF/KJP/CPB/SRT

NWS LWX Office Area Forecast Discussion