Arlington, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

947
FXUS61 KLWX 071824
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
124 PM EST Sat Mar 7 2026

.WHAT HAS CHANGED...
CAD steadily eroding from south to north for areas east of the
Blue Ridge. Temperatures quickly jump 10-15 degrees this
afternoon for areas that see clearing. Northeast MD stays under
clouds through this evening. Showers and thunderstorms starting
to develop, with the threat for severe storms greatest west of
the Blue Ridge through this evening.

&&

.KEY MESSAGES...
- 1) Showers and thunderstorms, some of which could be strong
  to severe, likely this afternoon to evening.

- 2) A strong cold front will cross the area late Wednesday
  into Thursday bringing the risk of strong to severe
  thunderstorms, along with a notable drop in temperatures late
  week.

&&

.DISCUSSION...

KEY MESSAGE 1..Showers and thunderstorms, some of which could be
strong to severe, likely this afternoon to evening.

The CAD wedge is steadily eroding from south to north for areas east
of the Blue Ridge. We likely get some sunshine here in the DC metro
by late afternoon, but areas in north/northeast MD will stay in the
CAD through around sunset. Temperatures have been adjusted
accordingly, but still a bit difficult to time the exact erosion of
the CAD. Most ares south of I-66 should reach the upper 60s to 70s
once the clouds break, with 70s expected west of the Blue Ridge (50s
to 60s in the Alleghenies). For those in the Baltimore metro to
points north/east, the warmer temps in the upper 50s to lower 60s
will arrive after sunset. Expect a very mild night across the area
in general as the cold front slowly moves through. Passing showers
and drizzle are likely in many areas with temps in the 60s.

Visible satellite imagery as of 1 PM shows a widespread cu field
across the OH Valley ahead of an approaching cold front. There is an
impressive low-level wind field in the warm sector with SW gusts of
30-35kt observed in parts of OH/western PA/WV in the last few hours.
The VWP from KPBZ radar shows strengthening low-level winds just off
the surface, which is producing around 30-35 kt of shear and 0-1km
SRH values in excess of 100 m2/s2. Ample heating and dew points in
the 50s to around 60F ahead of the front will yield MLCAPE values
around 500-1000 J/kg. Thunderstorms have already developed along the
front in IN/IL, and these should continue to progress/organize as
they move into OH/WV later this afternoon.

We are already seeing a few thunderstorms develop just east of the
Alleghenies, with additional isolated storms possible along the
I-81 corridor this afternoon. The main threat from these storms
will be hail and possibly some damaging winds (though maybe not
if these storms are primarily elevated due to lingering low-
level inversion over the northern Shenandoah Valley).

As the main line of convection moves across the Alleghenies some
severe thunderstorms are possible, with damaging wind gusts as the
main threat. Hail is certainly possible given 500mb temps are right
around -14C. Nearly unidirectional SW winds will promote a linear
structure and/or broken line segments as the main convective mode.

It is worth noting there is a low, conditional tornado threat as the
main line moves through western MD / Potomac Highlands this evening.
The recent SPC update introduced a hatched SIG1 across the OH
Valley, reaching very close to far western MD. The SIG1 hatched area
means the reasonable high-end intensity for any tornado that occurs
could be up to an EF-2. The main thing working against convection
will be the stabilizing boundary layer this evening, with convection
becoming elevated as it moves east of the Alleghenies.

The stronger convection wanes late this evening as the front slowly
sages through the region. A period of low clouds and drizzle is
likely tonight, though not expecting widespread fog like we had this
past week. The front pushes through Sunday afternoon, with skies
clearing from northwest to southeast. Most of the area should see
sunshine for a few hours late afternoon tomorrow as sunset is an
hour later with EDT returning. Highs in the 60s to lower 70s.

Closer to normal temperatures Sunday night in the 40s. Very warm and
dry to start next week as highs reach the 70s, with low 80s possible
in central VA Tuesday.


KEY MESSAGE 2..A strong cold front will cross the area late
Wednesday into Thursday bringing the risk of strong to severe
thunderstorms, along with a notable drop in temperatures late week.

The tug of war between early Spring and late Winter comes to an end
midweek as a strong cold front crosses the region. Most of 06z/12z
deterministic/ensemble guidance does not have a front crossing until
the late Wednesday and Thursday timeframe. This would give us well
above average temps in the upper 70s and low 80s (low 70s mountains)
Wednesday before a slow cool down Thursday into the 50s and 60s (40s
mountains). This would also mute any significant cold air advection
until late Thursday night (where lows fall into the mid 20s and low
30s) and Friday (with highs in the mid 40s and low to mid 50s).

Outside of the notable 20-30 degree drop in temperatures mid to late
week, will be the concern for severe weather along the front. This
is due largely in part to the stark contrast in airmass and notable
lift along the front/incumbent upper level trough as it swings
through. Timing will be everything here in order to maximize
instability and shear. Right now, the severe threat is non zero with
a focus west of Blue Ridge/Alleghenies Wednesday and east of the
mountains Thursday pending the progression of the front. An earlier
front Wednesday afternoon and evening could spell more of a severe
weather concern west of of the Blue Ridge where a later front
Wednesday night working east toward the metros mid-Thursday morning
could limit the threat east of I-95. SPC currently highs a 15
percent probability zone for severe storms west of the Alleghenies
on Day 5 (Wednesday afternoon).

This aligns with 15 to 30 percent CSU probabilities for all severe
weather hazards in this same area 12z Wednesday through 12z
Thursday. The CSU learning machine probabilities focus the 15 to 30
percent probs areawide including the metro area Wednesday afternoon
through THursday morning while bleeding residual 5 to 15 percent
probs for all severe probs east of I-95 Thursday morning into
Thursday afternoon. NSSL probabilities have a similar thinking with
the potential for widespread thunderstorms (some of which could be
strong to severe) during the Wednesday and Thursday timeframe. Any
storms that due for will pack the threat of wind and heavy rainfall.
As for flooding, it`s still too early to tell if there will be
issues outside the mountains given the added saturation over the
past few days and continued drought concerns. Rain may change to
snow over the Alleghenies Thursday morning into Thursday afternoon
as cold air advection funnels in. Any accumulations will be light
with upslope likely lingering into Friday.

High pressure builds back into the area briefly Friday before
another front crosses this weekend.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
As the CAD wedge slowly erodes from south to north most terminals
will return to VFR conditions by late afternoon. The IFR CIGs could
linger at BWI/MTN the longest, and it might remain IFR through late
this evening at MTN. A cold front sags south into the area tonight,
bringing some periods of showers and drizzle, with the possibility
of lower CIGs/VSBY. Not expecting widespread LIFR conditions like
have occurred this past week, but some restrictions are possible
through Sunday morning.

The cold front pushes through the area Sunday afternoon, then VFR
conditions prevail Sunday night through Tuesday.

Sub-VFR conditions look to impact the area late Wednesday into
Thursday as a strong cold front crosses the region. The front will
bring increased chances for showers and even a few thunderstorms
amongst the terminals. Southerly winds Wednesday will likely switch
to the west and northwest Thursday with gusts up to 25 kts. Winds
decrease Friday as brief high pressure settles nearby.

&&

.MARINE...
Southerly winds pick up this afternoon, with SCA conditions expected
this evening into tonight. The colder waters of the bay likely limit
the mixing of stronger winds off the surface, but should be enough
mixing to still gust around 20-25 knots. Winds could still be around
20 kt Sunday morning, then winds turn northwest Sunday afternoon
behind a cold front. Sub-SCA winds prevail Sunday night through
Tuesday.

SCA conditions are possible on Wednesday (in southerly channeling)
and Thursday (post frontal northwest flow) as a strong cold front
pushes through. A few thunderstorms or gusty showers may accompany
this front, Thursday afternoon. Gusts of 20 to 30kts are expected
across the waters with locally higher gusts in any thunderstorms
that may form. Winds will slowly fall back below SCA levels Thursday
night into Friday with SCAs returning Friday afternoon into Saturday
ahead of an additional frontal boundary.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...None.
VA...None.
WV...None.
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 until 5 AM EST Sunday for ANZ535-536.

&&

$$

DISCUSSION...KRR/EST
AVIATION...KRR/EST
MARINE...KRR/EST