Helen Maryland Weather Forecast Discussion

347
FXUS61 KLWX 121936
AFDLWX
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
336 PM EDT Sun Oct 12 2025
.SYNOPSIS...
A coastal low near the Carolina coast will move north along the Mid-
Atlantic coast through the start of the week. The low will move
out to sea Tuesday into Wednesday. A dry cold front will cross
the area Wednesday, followed by Canadian high pressure building
in from the northwest late in the week.
&&
.NEAR TERM /THROUGH MONDAY/...
Low pressure is located between Cape Fear and Cape Hatteras this
afternoon. Upper lows remain separate near western New York and
the southeast coast. Channel 9/10 water vapor imagery and the
12Z IAD sounding indicate an abundance of mid level dry air
across much of the forecast area. This has kept steadier rain at
bay across far southern Maryland, and even some thinning of
cloud cover across northern Maryland. Earlier light rain and
drizzle has largely dissipated. A tight pressure gradient
between the low and high pressure over maritime Canada is
resulting in strong northeast winds, with gusts generally in the
20-30 mph range, though some higher gusts may be seen along the
immediate Chesapeake Bay.
The surface low will gradually move northward toward the
Delmarva through Monday as the two upper lows consolidate near
the Mid Atlantic coast. This will eventually draw increased low
level moisture into the area tonight into Monday morning.
However, some mid level dry air will remain in place, so
precipitation may be more drizzly in nature. The greatest
chances for measurable rain will be east of the Blue Ridge, and
especially east of I-95. Winds may subside slightly tonight, but
remain elevated through Monday with the pressure gradient in
place. Monday`s gusts will again be in the 20-30 mph range. With
the clouds and drizzly conditions, temperatures will move very
little. Lows tonight will be in the 50s, with highs on Monday in
the upper 50s and lower 60s. The southern and western periphery
of the CWA will see drier conditions and perhaps even a few
breaks of sun, so temperatures may sneak into the mid to upper
60s in these areas.
&&
.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
The phased upper trough shifts offshore Monday night through Tuesday
night. Some uncertainty about how the surface low pivots around,
or if a second one eventually develops. That might affect how
long precipitation chances and clouds hang around. Overall, rain
chances should taper off Monday night, with clouds finally
clearing on Tuesday. Breezy conditions will persist, but winds
won`t be quite as strong as Sunday and Monday. Increased
sunshine should allow highs to reach the upper 60s to mid 70s
Tuesday. Overnight lows will range from the mid 40s to mid 50s.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
A strong upper trough remain over the northeast CONUS through
the end of the week. A very strong piece of shortwave energy will
dive south through our region, pushing a pretty decent cold front
through the region, albeit dry in nature. Again, expect temperatures
in the mid-upper 60s to low 70s (low 60s in the mountains), but
cooler air will be ushered in for the overnight into Thursday. Dry
conditions will continue Thursday, with high temperatures in the low
60s for most (50s in the mountains). Could be looking at
frost/freeze potential, especially west of the Blue Ridge,
Thursday night as winds become light.
Dry conditions continue through Saturday as high pressure remains in
control of the weather pattern. As the aforementioned trough finally
starts to shift towards the east, mid-level height rises will allow
for slightly warmer temperatures Friday, and then much warmer by
Saturday. Highs Friday reach the mid 60s before jumping into the
low to mid 70s by Saturday.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
The area will remain under the influence of coastal low pressure
through Tuesday morning. Some drier air attempting to work in north
of this system has kept rain at bay this afternoon and is allowing
ceilings to lift to VFR in spots. As the low drifts northward
tonight into Monday, more low level moisture will attempt to move
into the area. This will result in lowering ceilings and potential
for occasional light showers or drizzle. Have kept TAFs more
conservative than MOS/LAMP guidance through the night in MVFR vs.
IFR. HREF probabilities for IFR are very low, and elevated sustained
winds (potentially remaining 10-15 kt) may prevent ceilings from
lowering. Did maintain a period IFR Monday morning, as persistent
drizzle or light showers may aid in saturation. Otherwise, northerly
gusts of 20-25 kt will remain possible through Monday. MVFR ceilings
likely persist Monday night, although there is some potential for
IFR.
VFR conditions look to return sometime Tuesday morning to early
afternoon as the coastal low finally moves away from the area.
Northwest winds gust around 20 knots Tuesday afternoon.
VFR conditions are expected Wednesday through the end of the week as
high pressure takes hold once again. Winds remain elevated however,
with NW winds around 15 to 20 knots during each afternoon.
&&
.MARINE...
Coastal low pressure will continue to result in hazardous marine
conditions through tonight. Winds have been slow to ramp up, but
should still see a period of gale conditions along the bay through
this evening, with high end advisory conditions as the low continues
to approach from the south. The threat of gale conditions should
gradually diminish late tonight into Monday morning. Some guidance
indicates a renewal of gale conditions along the middle bay Monday
evening into potentially Monday night as the low makes its closest
approach to the Delmarva. However, confidence is too low for
extending the warning at this time. Regardless, advisories will
likely need to be extended into Tuesday as the low pivots and
eventually moves out to sea.
By Wednesday, winds turn a bit more NW and begin to taper off as the
pressure gradient weakens over the region. However, do still expect
frequent gusts up to 20 knots, at least for much of the day, so SCAs
remain likely during this period. This will continue into Thursday
as well, with SCAs likely to continue.
&&
.TIDES/COASTAL FLOODING...
Water levels are now steadily climbing ahead of low pressure off
the Carolina coast. However, strong northeast winds will also
tend to keep the higher surge shoved to the south. Thus expect
the peak tide to occur this evening, with the highest departures
in the middle bay and lower Potomac. Will have to monitor St.
Marys/Straits Point which will be very close to moderate flood
stage. Other locations will see minor. Have included Washington
DC in an advisory now as well.
There`s some uncertainty how long the surge remains in place.
Have extended advisories for Dahlgren and Solomons to the
Monday morning high tide where confidence is the highest, but
other locations may reach minor flood as well.
As the system move to the Delmarva Monday, strong N/NW winds
are forecast to push tides out rapidly, potentially leading to
blowout conditions. The latest guidance is less suggestive of
this outcome however, with high waters levels potentially
sloshing back northward and leading to additional minor flooding
during the middle of the week.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Coastal Flood Advisory from 10 PM this evening to 4 AM EDT
     Monday for DCZ001.
MD...Gale Warning until 6 AM EDT Monday for MDZ008.
     Coastal Flood Advisory from 8 PM this evening to 3 AM EDT
     Monday for MDZ014.
     Coastal Flood Advisory until 11 AM EDT Monday for MDZ016.
     Coastal Flood Advisory until 10 PM EDT this evening for MDZ017.
     Coastal Flood Advisory until 10 AM EDT Monday for MDZ018.
VA...Coastal Flood Advisory from 10 PM this evening to 4 AM EDT
     Monday for VAZ054.
     Coastal Flood Advisory until 11 AM EDT Monday for VAZ057.
WV...None.
MARINE...Gale Warning until 6 AM EDT Monday for ANZ530-531-538-539.
     Gale Warning until 8 AM EDT Monday for ANZ532>534-537-540>543.
     Small Craft Advisory until 6 PM EDT Monday for ANZ535-536.
&&
$$
SYNOPSIS...ADS
NEAR TERM...ADS
SHORT TERM...ADS
LONG TERM...CJL
AVIATION...ADS/CJL
MARINE...ADS/CJL
TIDES/COASTAL FLOODING...ADS

NWS LWX Office Area Forecast Discussion