Office: LWX
FXUS61 KLWX 210711
AFDLWX
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
311 AM EDT Tue Oct 21 2025
.SYNOPSIS...
High pressure shifts offshore today as a cold front approaches and
moves across the forecast area tonight. Surface high pressure builds
overhead through the weekend.
&&
.NEAR TERM /THROUGH TONIGHT/...
Surface high pressure shifts offshore today with return flow
ushering in warmer temperatures. High temperatures will be in the
upper 60s to 70s with the Alleghenies staying in the 50s. An
approaching cold front will push through the forecast area this
evening and into the overnight. As the cold front pushes
through, 00Z guidance shows a line of light rain showers moving
through the area. The line of showers is forecast to move
through this evening after sunset, with precipitation chances
highest for those east of the Blue Ridge.
Mountain rain showers persist in the Alleghenies overnight with
dry conditions expected elsewhere after midnight. Overnight low
temperatures will be in the 40s for most as the metros and those
near the waters stay in the 50s. Those at higher elevations in
the Alleghenies drop into the 30s.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
Gusty west winds result in mountain rain showers Wednesday and
Thursday. Elsewhere, dry conditions and limited cloud cover are
expected as high pressure builds to the south. West winds gust
up to 25 knots on Wednesday before becoming light overnight.
West/southwest gust up to 20 knots Thursday before diminishing
overnight.
Temperatures will be similar each day, with highs in the 50s
and 60s (40s Alleghenies). Overnight lows on Wednesday will be
in the upper 30s to 40s across the forecast area. On Thursday
night, temperatures will be slightly cooler with most of the
area in the 30s. The exception will be the metro areas and those
near the waters, where low temperatures will stay in the 40s.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
Upper low/troughing over eastern Canada and northeastern US will
start to weaken and pull to the east by the end of the week. This
will allow the surface high to the west to finally spread eastward
Friday into Saturday. Dry conditions can be expected Friday with
continued slightly below normal temperatures.
Uncertainty gradually increases over the weekend into early next
week with a complex upper level pattern. At least at this time, any
notable systems appear unlikely as troughing remains across the
Plains or Mississippi Valley. However, warm advection overrunning
will result in increased cloud cover and perhaps a few light showers
at times. The cloud cover and onshore flow may be enough to keep
temperatures below normal.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
VFR conditions are expected across all terminals today as high
pressure shifts offshore and a cold front approaches from the
west. Southerly winds start off light, blowing 5 to 10 knots
early this morning. Southwest winds gust 15 to 20 knots this
afternoon before becoming light tonight. Have a PROB30 in all
TAFs for this evening as a line of light rain showers moves
across the terminals. VFR conditions are expected to continue,
although lower ceilings and reduced visibilities are possible.
Winds shift to westerly in the wake of the cold front on
Wednesday, gusting 15 to 25 knots in the afternoon. VFR
conditions continue Wednesday and Thursday with west/northwest
winds gusting 15 to 20 knots on Thursday. Winds diminish
Thursday evening, blowing 5 to 10 knots overnight.
VFR conditions are likely Friday and Saturday under high
pressure.
&&
.MARINE...
Southerly winds today gust up to 25 knots with a Small Craft
Advisory in effect. Small Craft Advisories are likely through
Wednesday afternoon as winds shift to westerly tonight in the
wake of a cold front. West/northwest winds gust around 20 knots
across the waters on Wednesday before diminishing overnight into
Thursday. Winds increase again on Thursday with additional Small
Craft Advisories possible.
Marginal SCA conditions may linger into Friday in WNW flow. Winds
will finally diminish Friday night into Saturday as high pressure
moves overhead.
&&
.TIDES/COASTAL FLOODING...
Southerly winds this morning combined with snap-back lead to
rising tidal anomalies. Sensitive tidal locations are forecast
to hit action stage during high tide this afternoon and evening.
Annapolis is forecast to hit Minor flood stage later this
afternoon.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Small Craft Advisory from 11 AM this morning to midnight EDT
tonight for MDZ008.
VA...None.
WV...None.
MARINE...Small Craft Advisory from 11 AM this morning to midnight EDT
tonight for ANZ530.
Small Craft Advisory from 11 AM this morning to 6 AM EDT
Wednesday for ANZ531>534-537>543.
Small Craft Advisory from 11 AM this morning to 8 PM EDT this
evening for ANZ535-536.
&&
$$
SYNOPSIS...AVS
NEAR TERM...AVS
SHORT TERM...AVS
LONG TERM...ADS
AVIATION...ADS/AVS
MARINE...ADS/AVS
TIDES/COASTAL FLOODING...AVS
