390
FXUS61 KLWX 070846
AFDLWX
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
346 AM EST Sat Mar 7 2026
.WHAT HAS CHANGED...
No significant changes to the forecast this morning, but added a
new key point regarding a strong frontal passage by the middle
of next week.
&&
.KEY MESSAGES...
- 1) Rain chances continue through Sunday, as multiple fronts
impact the region. This will be followed by a warming trend
into next week.
- 2) A strong cold front is likely to push through the region
midweek, bringing back chances for significant rain followed
by a sharp drop in temperatures.
&&
.DISCUSSION...
KEY MESSAGE 1...Rain chances continue through Sunday, as multiple
fronts impact the region. This will be followed by a warming
trend into next week.
Onshore flow has continued to funnel in a potent marine layer
this morning, with some very low stratus and even some fog/mist.
This is going to take some time to scour out this morning, but
do expect it to occur a bit quicker than previous days. This is
because high pressure will shift further east today, while a
potent shortwave and associated area of low pressure rapidly
track northeastward from the Upper Midwest/Great Lakes toward
Quebec. As this occurs, winds at the surface will turn southerly
and winds aloft will increase out of the southwest. This will
likely allow the cold air damming wedge to finally break to the
east of the Blue Ridge by the afternoon and evening hours. As a
result, temperatures are forecast to be a good bit warmer today
further northeast, with most of the forecast area (with the
exception being Northeast Maryland) climbing into the 60s and
70s by mid-late afternoon.
The combination of deeper moisture advecting into the area in
southerly flow (dewpoints reaching into the upper 50s to lower
60s), daytime heating, and glancing ascent as the shortwave
passes to our north and west will enable showers and
thunderstorms to develop by later this afternoon into the
evening. This will come in two rounds, with the first round
forming within a surface trough just to the east of the
Alleghenies during the mid-late afternoon hours. Model soundings
show a fair amount of dry air in place aloft, and large scale
forcing for ascent won`t be overly strong, so areal coverage
with this first round of storms is only expected to be isolated
to scattered in nature. If storms do become well established,
the background environment will have enough instability (around
1000 J/kg of MLCAPE) and shear (around 40 knots in the 0-6 km
layer) to promote updraft rotation. Isolated instances of
damaging winds or hail may be possible with these storms as they
move eastward from the Potomac Highlands toward the I-81
corridor and then the Blue Ridge/Catoctins during the mid-late
afternoon hours. Conditions will likely remain dry to the east
of US-15 during the daylight hours.
A second round of pre-existing storms will approach from the
Ohio Valley, reaching the Allegheny Front around sunset. This
round of storms could be well organized into a squall line, and
may potentially be quite intense. With the loss of daytime
heating, the trend will likely be downward with the strength of
this activity as it moves into our area, but damaging winds may
still be possible, especially along and west of the Allegheny
Front. Large scale forcing for ascent may enable these storms
to hold together in a weakened form as they move eastward across
the forecast area during the first half of the night. SPC has
Garrett County in Slight Risk for severe thunderstorms, with
locations further east to about US-15 in a Marginal Risk.
The actual surface cold front will move through the area late
tonight into Sunday morning. There is still some disagreement
amongst guidance regarding the timing of the frontal passage,
and how much daytime heating will occur ahead of the front
during the day on Sunday. We`ll likely have some lingering cloud
cover and showers during the morning ahead of the front.
Depending on how fast the front progresses, some daytime heating
could occur ahead of the front across southern Maryland,
potentially leading to the development of a few thunderstorms.
Clearing is expected from northwest to southeast during the
afternoon and evening hours as drier air starts to work in
behind the front. High temperatures on Sunday will be in the 60s
and 70s for most, with 50s in the mountains.
Temperatures mainly in the 70s and 80s Monday and Tuesday under
partly to mostly sunny skies as high pressure builds back into
the region.
KEY MESSAGE 2...A strong cold front is likely to push through
the region midweek, bringing back chances for significant rain
followed by a sharp drop in temperatures.
Relatively calm and sunny conditions are likely to continue on
Tuesday, before zonal flow aloft starts to transition to an upper
trough centered over the Northeast on Wednesday. This will result in
a strong cold front set to push through the East Coast over the
Wednesday/Thursday timeframe, likely bringing significant rain to
the region followed by a sharp drop in temperatures by the end of
next week. The ECMWF and GFS are currently showing this temperature
drop to start on Thursday night, and there are early signals showing
lows to shift back to sub-freezing temps out over the mountains for
a period as high pressure takes over towards the end of the week.
Within the rest of the region, temps could drop to the 40s-50s on
Thursday and Friday.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
LIFR CIGs are being observed at all terminals at this time, and
that will continue through this morning for all. Patchy dense
fog is still possible, but likely closer to sunrise, and very
brief. Either way, some VSBY reductions likely during that
period, and CIGs will not improve until later.
Gradual improvement is expected through the day, with conditions
clearing out first at CHO, and last at MTN. CIGs will likely
climb a few hours quicker than yesterday as winds turn out of
the south and pick up to around 15 to 20 knots. Showers and
thunderstorms will approach from the west this evening, but
will likely be weakening as they do so. For now, left the
mention out of any TAFs, but will continue to monitor as the day
moves on.
A cold front will move through on Sunday, leading to a return
to VFR conditions and a shift to westerly winds.
Prevailing VFR conditions across terminals on Monday and Tuesday,
followed by periods of lowered CIGs and VSBYs associated with a
strong cold front impacting the region between late Wednesday
and Thursday. Southerly winds likely to shift northwesterly on
Wednesday, with gusts up to 20 knots possible.
&&
.MARINE...
Winds will turn out of the south today, and remain sub-SCA in
nature through much of the day. However, am expecting winds to
pickup a bit during the afternoon/evening, with SCAs being
issued as a result. Warm air moving over cooler waters will
likely be a limiting factor to some extent, especially over the
wider waters, but think there has been enough of a trend
upwards to expect some solid 20 knot gusts.
Winds drop below SCA criteria by Sunday morning and shift out
of the west by Sunday afternoon as a cold front moves over the
waters.
No marine hazards Monday through Tuesday night. Winds generally
south to southwest 5 to 10 knots.
SCA conditions are possible on Wednesday, with gusts up to 20 knots
throughout the bay currently forecasted associated with a strong
cold front pushing through midweek. Winds may further strengthen on
Thursday before gradually decreasing towards the end of the
week.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Dense Fog Advisory until 10 AM EST this morning for MDZ501-510.
VA...Dense Fog Advisory until 10 AM EST this morning for VAZ026>031.
WV...Dense Fog Advisory until 10 AM EST this morning for WVZ050>053-
055-503-504.
MARINE...Small Craft Advisory from 7 PM this evening to 5 AM EST Sunday
for ANZ531-532-538>540.
Small Craft Advisory from 7 PM this evening to 8 AM EST Sunday
for ANZ533-534-537-541>543.
Small Craft Advisory from 2 PM this afternoon to 5 AM EST
Sunday for ANZ535-536.
&&
$$
DISCUSSION...CJL/KJP/SRT
AVIATION...CJL/KJP/SRT
MARINE...CJL/KJP/SRT
NWS LWX Office Area Forecast Discussion