Weyers Cave, Virginia Weather Forecast Discussion

040
FXUS61 KLWX 201840
AFDLWX
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
240 PM EDT Sat Sep 20 2025
.SYNOPSIS...
Surface high pressure wedges south from eastern Canada and northern
New England today while a backdoor cold front stalls across the
Alleghenies and southwest Virginia. Scattered slow moving
showers and thunderstorms will accompany the boundary. Wedging
high pressure remains overhead Sunday with a warm front set to
lift through the area Monday. Widespread precipitation chances
arrive with a slow moving cold front by the middle of next week.
&&
.NEAR TERM /THROUGH TONIGHT/...
Sfc analysis indicates backdoor cold front is through the
majority of the forecast area and has stalled from near Nelson
County, VA back up through Pendleton County, WV. This frontal
positioning will be the main focus for the corridor of where
showers and thunderstorms develop this afternoon/evening.
Further east, more isolated convection is expected associated
with a piece of shortwave energy. Storms in the mountains look
to be slow moving and perhaps tied to the terrain given
weak/veering upslope flow and shear less than 25 kts. Some western
mountain locations mentioned above could pick up a quick 1-2
inches of rain with locally heavier amounts if convection locks
onto the terrain. Any rain will be welcomed especially over the
Alleghenies and Shenandaoh Valley where moderate to severe
drought conditions persists. SVR threat is rather low with
convection this afternoon.
Elsewhere, dry conditions prevail with partly cloudy skies
expected. Clouds will likely increase late in the day and during
the evening hours as the shortwave disturbance passes to the
south.
Lows tonight will fall back into the upper 50s and low 60s as a
maritime airmass takes hold especially east of the Blue Ridge.
Patchy fog is possible overnight, especially in areas that
receive rain today.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
High pressure will remain nearby Sunday with the aforementioned
stalled frontal boundary to the south kind of washing out across
southern VA before retreating northward as a warm front late
Sunday night into Monday.
For Sunday, onshore flow will ensue prior to the warm frontal
passage yielding cooler temperatures and increased low level
cloudiness across the region. Some patchy drizzle and light
shower activity also cannot be ruled out during the morning
hours. Highs Sunday will range from the low to mid 70s across
the mountains and northeast/central MD to upper 70s across
central VA. The stratus looks to hold tough across most of the
area throughout the day likely eroding across central/eastern VA
and the western Alleghenies Sunday afternoon and evening as a
warm front lifts northward into the region.
The warm front continues to lift north Sunday night into Monday
while surface high pressure shifts off the northern New England
coast. As a result, expect the wedge to continue to erode as
southerly return flow takes over yielding warmer temperatures and
increased moisture across the region. Lows Sunday night will fall
back into the upper 50s and low to mid 60s. Some fog cannot be ruled
out especially in areas where the stratus clears outs.
Highs Monday will climb back into the upper 70s and low to mid
80s (low 70s mountains). A shower or thunderstorm cannot be
ruled out west of I- 81 given the proximity of the warm front
and piece of shortwave energy riding to the north. Coverage will
be spotty to scattered given the residual dry air leftover from
high pressure departing offshore. Any mountain shower and
thunderstorm activity will come to an end by Monday evening with
lows Monday night falling back into the upper 50s and low to
mid 60s.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
The long term period consist of daily precipitation chances as a low
pressure system track east from the central CONUS Tuesday through
Friday. As the surface low tracks towards the forecast area, the
associated cold front drops south from Pennsylvania before stalling
overhead through the end of the week. Daily showers and
thunderstorms across the area are expected with greatest coverage
likely on Friday as a secondary cold front approaches the forecast
area. Given recent dry conditions and ongoing drought, rainfall
looks to be beneficial at this time.
Tuesday will be the warmest day of the period with high temperatures
in the 80s for most (70s mtns). Temperatures gradually cool each day
Wednesday through Friday with highs in the 70s (60s mtns) by the end
of the week. Overnight low temperatures will be in the 50s to 60s
each night.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
Wedging high pressure will build south from northern New
England while a cold front remains stalled south and west of the
area. The stalled front will lead to temporary sub-VFR
reductions over portions of the southern Shenandoah Valley and
Allegheny Highland terminals (i.e SHD, ROA, LWB, and CHO) this
afternoon and evening. Elsewhere, dry conditions will prevail
with mostly sunny to partly cloudy skies to start and increasing
clouds this evening as onshore easterly flow increases. Light
northeast winds this morning will shift to the east this
afternoon at 5 to 15 kts. With a subtle pressure gradient in
place between the front stalling to the south of the area and
wedging high pressure to the north expect gusts between 10-15
kts this afternoon and evening mainly at terminals along the
ridges and close to the water. Sub-VFR conditions look to return
as early as this evening and especially tonight as onshore flow
increases.
Low level clouds (i.e stratus) will lead to sub-VFR conditions
especially at terminals east of the Blue Ridge Sunday into Sunday
night. Some light drizzle and showers cannot be ruled out although
confidence remains low. VFR conditions return Monday into Tuesday as
a warm front lifts through the region. A shower or thunderstorm
cannot be ruled out west of a line from KHGR/KMRB to KCHO as the
warm front lifts north and several pieces of energy pass to the
north and west of the region. This may lead to temporary sub-VFR
reductions on Monday afternoon. The front combined with high
pressure moving offshore will shift the winds from the east on
Sunday back to the south Monday. Expect gusts between 10 to 15 kts
mainly during the afternoon and evening hours (especially at
terminals near the waters and along the ridges).
The long term period consist of daily precipitation chances as a low
pressure system track east from the central CONUS Tuesday through
Friday. As the surface low tracks towards the forecast area, the
associated cold front drops south from Pennsylvania before stalling
overhead through the end of the week. Daily showers and
thunderstorms across the area are expected with greatest coverage
likely on Friday as a secondary cold front approaches the forecast
area. Given recent dry conditions and ongoing drought, rainfall
looks to be beneficial at this time.
Tuesday will be the warmest day of the period with high temperatures
in the 80s for most (70s mtns). Temperatures gradually cool each day
Wednesday through Friday with highs in the 70s (60s mtns) by the end
of the week. Overnight low temperatures will be in the 50s to 60s
each night.
&&
.MARINE...
The front will stall south of the waters this afternoon with
winds turning back toward the northeast and easterly direction.
SCA conditions are possible over the open waters of the bay and
tidal Potomac tonight into Sunday with increased onshore
easterly flow. Given marginal nature and somewhat short
duration, may be best handled with a Marine Weather Statement.
The increase in winds is due in part to a tightened pressure
gradient between wedging high pressure to the north and a
dissipating front that will lift north as a warm front Sunday
into Monday. High pressure shifts offshore Monday while the warm
front lifts north of the waters. This will lead to southerly
channeling and an additional period of SCA conditions Monday
night into Tuesday morning.
Southwest winds on Tuesday shift to southeast on Wednesday, blowing
5 to 10 knots each afternoon. Daily shower and thunderstorm chances
are expected over the waters with SMWs possible, although
unlikely.
&&
.TIDES/COASTAL FLOODING...
Tide levels increase Sunday as onshore easterly flow raises
anomalies. Additional increases are possible Monday as high
pressure pushes offshore and southerly winds return bringing
more water northward. In turn, this may result in action stage
at several sites and minor tidal flooding at the more sensitive
locales.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...None.
&&
$$
SYNOPSIS...CPB/EST
NEAR TERM...CPB/EST
SHORT TERM...CPB/EST
LONG TERM...AVS
AVIATION...AVS/CPB
MARINE...AVS/CPB
TIDES/COASTAL FLOODING...EST

NWS LWX Office Area Forecast Discussion