Severn, Maryland 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

267
FXUS61 KLWX 041352
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
952 AM EDT Fri Apr 4 2025

.SYNOPSIS...
A front will waver across the Mid Atlantic through Sunday, when
it will finally push to the south as a cold front. A secondary
cold front will push through Monday night. Strong high pressure
will move in by mid-week.

&&

.NEAR TERM /THROUGH TONIGHT/...
The frontal boundary continues to slowly sag south through the
area this morning. As of 9AM, based on radar and surface
observations, the frontal boundary is loosely along US-48/I-66
from Petersburg to Fairfax, then sags along US-50 toward
Annapolis.

To the north of the boundary, cloudy skies and temps in the 50s
to low 60s continue through this afternoon. Light showers
continue right along the boundary through the afternoon, though
most of that precip is going to be on the light side east of the
Blue Ridge, with steadier (though brief) showers in the
Shenandoah Valley and Alleghenies.

A lull in precip is likely for several hours this afternoon as
the front sags south of I-66/US-48. Highs in Central VA are
forecast to reach the upper 70s to lower 80s, especially in
areas where mid/high level clouds break. There is some
uncertainty how far south the front moves before peak heating.
Somewhere near or south of I-64 there will be a sharp increase
in temperatures to the mid 80s.

Additional threats of showers and thunderstorms from mid
afternoon into the evening will be focused near the front
(southern half of the area and perhaps up the Alleghenies).
Shear/instability space along with CAM output suggests there
could be a few stronger storms in this zone, but ultimately the
front may undercut most of the development within our forecast
area.

The front remains south of the area tonight. Overrunning will
result in the potential for showers and drizzle along with low
clouds and fog. Lows settle in the 50s. Model soundings indicate
elevated instability also overspread the area tonight, meaning
some could hear a few rumbles of thunder. Isolated thunderstorms
have been added to the forecast for most of the area tonight.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
The front will attempt to lift north on Saturday but may have a
tough time doing so due to relatively light low level wind
fields and a sharp inversion due to the low clouds and drizzle.
This will result in another day of low confidence in the
temperature forecast with a potential range of 60 to 85 across
the forecast area. Even if the surface boundary gets hung up,
heights will rise slightly aloft and the main forcing and
moisture corridor will pivot north and west of the area.
Likewise, that will be the area that has the highest chance of
showers and a few thunderstorms during the afternoon and evening
hours.

As the pattern aloft begins to shift and a wave of low pressure
passes, the front will return southward as a cold front late
Saturday night into Sunday. This will slowly increase rain
chances from northwest to southeast. At this time, instability
looks fairly limited locally, resulting in a minimal chance for
any thunderstorms. With the front bisecting the area Sunday,
there will likely be another large range in temperatures from
the 50s in the northwest to near 80 in the southeast. Even
though the front will likely be south of the area by evening,
favorable upper level dynamics and a wave of low pressure riding
the boundary will renew rain chances across the area Sunday
night. At this time, all rain looks to be beneficial in nature.
Any precipitation which lingers the second half of the night
along the Alleghenies will start to change over to snow.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
Precipitation chances linger in the southeastern portions of the
forecast area on Monday, as a cold front departs off the Carolina
coast. Additionally, an area of low pressure located over the Great
Lakes will move north of the Mid-Atlantic on Monday, which will push
the associated cold front through the area Monday evening. This will
lead to a chance of upslope precipitation along the Alleghenies
overnight. High temperatures on Monday will be in the 50s to low 60s
with those at higher elevations staying in the 40s. Overnight lows
will be in the 20s to 30s in the wake of the cold front.

Conditions dry out areawide on Tuesday as Canadian high pressure
builds over the mid-atlantic through midweek. A much cooler air
mass will build overhead, with highs on Tuesday staying in the 40s
to low 50s (30s mtns). Overnight lows will be in the 20s and 30s.
Temperatures gradually warm each day with highs rebounding to the
50s and 60s on Thursday.

On Thursday, an area of low pressure develops over the central
CONUS, with the associated warm front draping across the Ohio River
Valley. As the frontal boundary approaches the area, precipitation
chances return, mainly for the western along and west of the
I-81.

&&

.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
A cold front drops south through the area, shifting winds to
the northwest and lowering ceilings to MVFR. Showers taper off
by late morning, but MVFR conditions are likely to continue
through the afternoon. CHO remains VFR the longest and could
have potential to see a thunderstorm during the late afternoon
to early evening. IFR conditions become increasingly likely
tonight along with some visibility reductions in mist and light
rain showers. Conditions may gradually improve Saturday, but
there is some uncertainty with how quickly the front returns
northward. BWI/MTN likely keep low ceilings the longest. Winds
eventually shift back to the south during this time.

Sub-VFR conditions will likely return Sunday and Sunday night as
the front drops back south through the area. Several waves of
showers are likely during this time, but thunder chances are
low. Gusty south winds shift to the north with frontal passage.

Winds remain out of the N/NW both Monday and Tuesday with VFR
conditions expected both days. Winds blow 5 to 10 knots on Monday
before increasing to gusts of 20 to 25 knots on Tuesday.

&&

.MARINE...
Winds have dropped below SCA levels across all the waters as of
mid this morning. A cold front continues to drop south through
the waters today, shifting winds from south to northwest. The
front eventually returns back north Saturday, but SE to S winds
should remain below advisory criteria through the day. Potential
for SCAs will return Saturday night in south flow and continue
Sunday into Sunday night as a cold front shifts winds back to
the north.

Small Craft Advisory criteria winds are possible in the southern
portions of the waters Monday morning. Winds diminish in the
afternoon, becoming light and variable overnight. Winds increase
early Tuesday morning with SCA conditions likely through the
afternoon.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...None.

&&

$$

SYNOPSIS...ADS
NEAR TERM...KRR/ADS
SHORT TERM...ADS
LONG TERM...AVS
AVIATION...KRR/ADS/AVS
MARINE...KRR/ADS/AVS