dc discuss
Office: LWX
FXUS61 KLWX 070225
AFDLWX
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
925 PM EST Thu Nov 6 2025
.SYNOPSIS...
High pressure will move offshore Friday, then a cold front will
cross the area Friday night. A stronger frontal system will
follow for late in the weekend ushering in the coldest airmass
of the season thus far for early next week.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
Other than a couple bands of thin cirrus, mainly clear skies
and light to calm winds are in place this evening. Some
locations have already dropped into the mid 30s given the dew
points in the mid 20s to lower 30s. Have lowered temperatures,
especially in valley/rural areas, given this setup. There are
two things that could cause temperatures to level off (or even
rise in the higher elevations) the second half of the night.
Some thicker cirrus will arrive from the Ohio Valley, and the
low level ridge will quickly move offshore, leading to
strengthening southwesterly low level flow. Regardless, think
the Frost Advisory along the I-95 corridor is still in good
shape (especially away from the downtown and bayshore areas).
Some of the colder low spots could even reach freezing.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
An upper trough of low pressure begins to dig in the Ohio Valley
on Friday as high pressure overhead moves to the east. A strong
cold front is expected to approach late Friday into Saturday.
This system will lack a substantial moisture connection to the
Gulf of America, thus making any significant rainfall hard to
achieve.
Also of note, fire weather could be an issued on Friday for the
Shenandoah Valley. For more details, see the Fire Weather
discussion below.
Dry conditions on Saturday, especially around midday into
Saturday afternoon behind frontal passage and a building high
pressure center. High temperatures will jump back well into the
60s and even low 70s.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
A weak wave of low pressure passes to our north early on Sunday,
then a second area of low pressure develops over our area and jets
off toward the northeast Sunday afternoon/evening. This is in
response to a powerful upper trough that swings from the Great Lakes
to the Mid-Atlantic. The low level cyclone will bring a period of
showers to the area Sunday morning to afternoon, then we should
clear out by late afternoon to evening. The high temp on Sunday is
going to occur early in the day as most areas get to the mid to
upper 60s, then cooler air drops temps back down by the evening.
For the Alleghenies, these rain showers will transition to snow
showers Sunday night as very cold air surges in. Accumulating snow
appears likely, but how much snow falls is still uncertain. The
ensemble consensus is around an inch or two of snow is possible,
though the spread is still from a few tenths to several inches.
Upslope snow showers in the Alleghenies continue into Monday as the
mid/upper trough goes overhead, then departs to the east on Tuesday.
Also, some of these snow showers could produce brief, intense bursts
of snow. The GFS snow squall parameter is showing this is most
possible Monday morning to afternoon when (and if) there is enough
moisture being fed from the Great Lakes. Any heavier bursts of snow
could add on to the snow totals. Still a lot of uncertainty, so
continue to monitor as this could result in travel disruptions for
some areas in the Alleghenies on Monday.
Cold and blustery conditions likely on Monday as highs struggle to
reach the mid to upper 40s. Northwest winds gusting around 15-20 mph
will keep wind chills in the 30s even during the middle of the day.
A widespread freeze is expected Monday night, which should
effectively end the growing season across the area. Lows are
forecast to drop to the 20s to around 30F, with upper teens in the
Alleghenies. Winds remain elevated, so wind chills will be in the
teens to low 20s, with single digits in the mountains.
The airmass moving into the region Monday night is going to be
extremely cold, possibly approaching some of the coldest temps ever
sampled for the Tuesday 12Z IAD sounding. The GFS and ECMWF both
show the potential for 500mb temps to be at or colder than -35C.
Looking at the NAEFS ensemble tables, the 500mb and 700mb temps are
around -4 standard deviations, and the 850mb temps are around
-3 standard deviations (the 850mb temps are forecast to be around
-10C to -13C). As a result, cannot rule out flurries or light snow
showers east of the Alleghenies Monday night if moisture can linger
before very dry air moves in.
Cold conditions remain Tuesday with temperatures similar to Monday,
though temps do start to moderate Tuesday night. Upper 50s to low
60s return Wednesday as gusty southwest winds return. Conditions
remain dry through mid-week though additional mountain snow showers
will be possible during this time.
&&
.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
VFR conditions with light to calm winds tonight as high pressure
pushes to the east.
An area of low pressure and potent cold front will begin to
approach the region Friday, so winds will increase substantially
out of the south, with gusts of 20-30 knots possible. As the
first in a series of cold fronts pushes through Friday, rain
showers are expected Friday evening into the early overnight.
These will be rather light in nature, so not completely sure
there will be reductions in ceilings or visibility below VFR.
VFR conditions return by Saturday morning, along with a wind
shift to the west, once frontal passage occurs.
An area of low pressure and cold front are forecast to move across
the area Sunday. This will bring periods of sub-VFR conditions
Sunday morning to afternoon, then conditions clear out by Sunday
evening. Becoming much colder on Monday as northwest winds
gust around 20-25 knots.
&&
.MARINE...
Light northwest winds this evening will become southwesterly by
daybreak as high pressure moves offshore.
Ahead of the next frontal passage, strong southerly winds will
bring SCA conditions to all waters Friday. An SCA was issued as
a result, and goes through Friday night.
Winds quickly taper off Saturday morning, turning out of the
west. SCAs should not be necessary until Sunday.
South to southwest winds ahead of a strong cold front on Sunday will
be gusting around 15-20 knots most of the day. SCA conditions fully
take hold Sunday night into Monday as northwest winds behind the
cold front gust between 20-30 knots. Gale conditions are possible in
the middle Chesapeake Bay Monday night.
&&
.FIRE WEATHER...
A cold front will approach the region Friday before moving
through Friday night into Saturday. Latest model guidance does
show an uptick in the RH values for the most part, but still
dropping into the upper 30s to low 40s during the afternoon for
most. Locally, the Shenadoah Valley may see much lower RH
values, particularly in the northern portions and up into
eastern WV/west-cetnral MD. The strong southerly winds will
create a downsloping effect on the northwest side of the Blue
Ridge mountains, and some guidance has RHs dropping back down
into the 20s. Additionally, winds tomorrow will be around 15-20
mph, with gusts up to 35 mph out of the south. The combination
of these two elements, paired with very dry fuels from recent
days, could lead to an elevated risk for wildfire spread Friday
afternoon. New starts may be more difficult, owing to cloudcover
and temps in the low 60s, but any ongoing fires could face some
challenges.
The aforementioned cold front pushes through Friday night, but
it likely to only yield a few hundredths of an inch of
precipitation in any one given location.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Frost Advisory from 1 AM to 8 AM EST Friday for DCZ001.
MD...Frost Advisory from 1 AM to 8 AM EST Friday for MDZ008-011-013-
014-016>018-504-506-508.
Small Craft Advisory from 9 AM Friday to 5 AM EST Saturday for
MDZ008.
VA...Frost Advisory from 1 AM to 8 AM EST Friday for VAZ053>055-057-
527.
WV...None.
MARINE...Frost Advisory from 1 AM to 8 AM EST Friday for ANZ530.
Small Craft Advisory from 9 AM Friday to 5 AM EST Saturday for
ANZ530>534-537-539>543.
Small Craft Advisory from 9 AM Friday to 1 AM EST Saturday for
ANZ535-536-538.
&&
$$
SYNOPSIS...CJL
NEAR TERM...ADS
SHORT TERM...CJL
LONG TERM...KRR
AVIATION...ADS/CJL/KRR
MARINE...ADS/CJL/KRR
FIRE WEATHER...CJL
