Bowie, Maryland 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

801
FXUS61 KLWX 142022
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
422 PM EDT Sun Jun 14 2026

.WHAT HAS CHANGED...
Storms have developed off to our west across West Virginia.
These storms will move into our area over the next few hours.

&&

.KEY MESSAGES...
- 1) Severe thunderstorms are expected later this afternoon
  into this evening.

- 2) Heat and humidity returns on Thursday along with the
  potential for strong to severe thunderstorms.

&&

.DISCUSSION...
KEY MESSAGE 1...Severe thunderstorms are expected later this
afternoon into this evening.

A closed mid-upper level low continues to circulate well off to
our north this afternoon across northern portions of
Ontario/Quebec in the vicinity of James Bay. A well defined
shortwave is evident on water vapor imagery to the south-
southwest of the closed upper low, extending southward across
Lake Superior toward the Upper Peninsula of Michigan, Lake
Michigan, and Illinois/Indiana. This disturbance will rotate
through the base of the broader trough over the course of the
day today, transitioning from a positive tilt currently to a
neutral tilt by this evening as it tracks through the Lower
Great Lakes and Ohio Valley. At the surface, an area of low
pressure is located just downstream of the upper low to the east
of James Bay. An occluded front extends southward across
northern portions of Quebec, before turning into a cold front
further south. This cold front then arcs southwestward across
Lakes Ontario and Erie, and then across Ohio and Indiana. As the
aforementioned shortwave progresses eastward, it will drive the
cold front further south and east. The cold front is expected
to reach the Allegheny Front around sunset, before progressing
southeastward through the remainder of the forecast area
overnight.

Deeper moisture is in the process of rapidly returning northward
into our forecast area. The 12z IAD sounding had a precipitable
water value of 1.05". The 18z IAD special sounding recently came
in with a PWAT value of 1.52", and PWATs are expected to
continue to rise to just below 2 inches by this evening. As the
deeper moisture rapidly returns northward, the thermodynamic
environment will rapidly become more favorable for the
development of thunderstorms locally. Thunderstorms have already
begun to to form off to our southwest across much of West
Virginia, southwestern Virginia, and Kentucky. This activity
will lift northeastward into our forecast area over the next
several hours. Locations to the west of the Blue Ridge will
experience impacts from these storms over the next few hours.

Model guidance suggests that a surface trough will develop across
the middle of the forecast area over the next couple of hours
(roughly in the vicinity of the Blue Ridge). This surface trough
will serve as a focused area of low-level convergence, likely
enabling pre-existing thunderstorms moving in from the southwest
to expand in coverage and intensify as they move further east
into a higher instability environment to the east of the Blue
Ridge.

As a result, the net expectation is for ongoing scattered
thunderstorms over WV to move in shortly. Coverage of these
storms will likely remain scattered to the west of the Blue
Ridge until they encounter the better surface convergence in the
vicinity of the Blue Ridge. The storms will then progress
eastward toward the I-95 corridor during the evening hours,
likely increasing in coverage/intensity as they do so. A surge
of higher theat-e air northward out of the Tidewater region this
evening may help to further invigorate storms as they move east
of I-95.

We`ll also have to monitor additional storms that have formed in
the Ohio Valley along/ahead of the sysetem`s cold front. A few
of the more isolated storms ahead of the front over northern WV
at the moment may move into western MD over the next few hours.
Additional storms have formed immediately along the cold front
in Ohio and will likely reach northwestern portions of the
forecast area (western MD and the WV Panhandle) around dark. The
tendency should be for this activity to weaken after sunset as
it moves further south and east, but a lower- end threat for
thunderstorms could potentially linger until around a little
after midnight along the I-95 corridor.

The background environment will be characterized by around 500-1000
J/kg of MLCAPE to the west of the Blue Ridge, and 1000-2000 J/kg
further east. Shear will also be on the increase as mid- upper
level winds strengthen ahead of the approaching shortwave. As a
result, effective bulk shear values are forecast to increase to
around 35-50 knots. Several hours of strong daytime heating have
allowed temperatures to climb into the low to mid 90s, and low-
level lapse rates to become very steep (8-9 C/km). DCAPE values
have also increased to around 1000 J/kg. Such an environment
will be very favorable for production of damaging winds in any
stronger storms that develop. Hodographs are relatively long and
straight with little in the way of low- level shear, but there
is some slight curvature noted near the surface. As a result,
the environment doesn`t appear to be overly favorable for the
development of tornadoes, but a tornado or two can`t be
completely ruled out, especially if storms interact with locally
backed winds in the vicinity of the bay breeze. Very warm
surface temps and poor mid-level lapse rates should limit the
hail threat somewhat, but an isolated instance or two can`t be
ruled out, given deep layer shear values that could potentially
support supercells. SPC currently has the entire forecast area
outlooked in a Slight Risk (level 2 of 5) for severe
thunderstorms, with damaging winds being the primary threat. It
should be noted that this is a higher end Slight Risk for
locations to the east of the Blue Ridge, with the 30 percent
wind contour. Storms are expected to be rather progressive
today, so the threat for flooding is expected to remain on the
lower side. However, a few instances of urban flash flooding
can`t be completely be ruled out as PWATs climb to nearly 2
inches. WPC has a Marginal Risk for excessive rainfall
outlooked to the east of the Blue Ridge.

As hinted at before, coverage of storms is expected to be lower
to the west of the Blue Ridge, with the peak threat occurring
during the mid-late afternoon hours. To the east of the Blue
Ridge (including the DC/Baltimore metros), the coverage of
storms is expected to be greater, and the timing is expected to
be later. For the DC/Baltimore metros, the highest coverage of
storms is expected to occur in the 6-10 PM window, although a
stray storm can`t be completely ruled out before, and there
could be a lingering low-end threat for a shower or storm until
1 or 2 AM. The system`s cold front will move through later
tonight, bringing chances for storms to an end as the cooler and
drier airmass behind the front moves in.

Much cooler, drier, and less humid conditions are forecast for
Monday and Tuesday. Mostly sunny skies are expected with high
temperatures in the upper 70s to around 80 and dewpoints in the
upper 40s to 50s. Winds will be out of the northwest on Monday,
before turning out of the south on Tuesday.

KEY MESSAGE 2...Heat and humidity returns on Thursday along with
the potential for strong to severe thunderstorms.

By mid-week, expect an increase in temperature and humidity levels.
The large-scale pattern remains much the same as an expansive area
of lower heights prevail over central/eastern Canada. To the south
of the broad upper low, a series of shortwaves will race eastward
across the northern tier of the country. This maintains a forecast
full of temperature and humidity rises and falls, as well as
periodic episodes of strong to severe thunderstorms.

On Wednesday, a shift to south to southwesterly return flow will aid
in ample warming along with increased moisture/humidity levels. This
ushers high temperatures back into the mid/upper 80s along with a
few showers and thunderstorms, especially along and east of I-95.

A more active day lies ahead for Thursday as a pronounced shortwave
begins to dig across the Midwest and Ohio Valley region. A
preponderance of the 12Z guidance support ample mid-level flow on
the order of 40 to 50 knots overspreading the area. This occurs in
accordance with increasing temperatures and dew points that return
to near 70 degrees. While mesoscale details will likely change, the
combination of ample instability and vertical shear is the main
reason the Storm Prediction Center has maintained a risk area since
yesterday/Saturday. Continue to monitor the latest forecast as
details will change in the days ahead.

Behind this system and associated cold frontal passage, expect
another period of tranquil weather Friday into much of next weekend.
This favors seasonable temperatures but with forecast dew points in
the 50s. Another frontal system may near the region next Sunday, but
any impacts are of low confidence at this time.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
Southerly winds and VFR conditions are expected through this
afternoon, with gusts to around 20-25 knots. Thunderstorms are
expected to develop across the area this afternoon/evening.
Confidence is currently low on timing at individual locations,
so have maintained PROB30s. TEMPOs or prevailing groups will
likely be needed as we move closer in time and confidence
increases with respect to exact timing. The threat for
thunderstorms will gradually wind down through the evening.
Winds will shift to out of the northwest behind a cold front
tonight. Gusts to around 20-25 knots may be possible at times
later tonight within northwesterly flow. VFR conditions and
lighter northwest winds are expected on Monday. Continued VFR
conditions are expected on Tuesday as winds become light out of
the south.

A return of more active weather comes on Wednesday, but particularly
on Thursday. Any restrictions mid-week should be brief and tied
to the D.C. and Baltimore terminals. A more potent frontal
system begins to impact the region on Thursday which favors a
threat for strong to severe thunderstorms. Any restrictions will
be tied to this convection with improving conditions by Friday
as high pressure returns. The mid/late week forecast winds will
switch from southwest to westerly behind the cold front, with
the strongest winds likely on Thursday with general gusts around
20 to 25 knots.

&&

.MARINE...
Southerly winds are expected over the waters today. SCAs are in
effect for all waters through this evening, and tonight for
southern waters. Thunderstorms will likely impact the waters
this afternoon/evening, with SMWs likely being needed. Damaging
winds will be the primary threat, but a stray waterspout or
instance of large hail can`t be ruled out. A cold front will
move over the waters tonight, shifting winds around to out of
the northwest. The SCA for later tonight may eventually need to
be expanded to all waters. Winds will remain out of the
northwest on Monday, but are expected to drop below SCA levels
by mid- morning. Sub-SCA level southerly winds are forecast for
Tuesday.

Some isolated convection is possible over the waters on Wednesday,
but the greater threat looms for Thursday as a potent frontal system
approaches from the west. Special Marine Warnings will likely be
needed at times, particularly during the afternoon/evening hours.
The convective threat abates by Friday behind the cold front. For
Small Craft Advisories, these will likely be needed on Thursday with
background southerly gusts around 20 to 25 knots.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Small Craft Advisory until 6 AM EDT Monday for MDZ008.
VA...None.
WV...None.
MARINE...Small Craft Advisory until 6 AM EDT Monday for ANZ530>534-537-
     539>541-543.
     Small Craft Advisory until 11 PM EDT this evening for ANZ535-
     536-538-542.

&&

$$

DISCUSSION...BRO/KJP
AVIATION...BRO/KJP/CPB
MARINE...BRO/KJP/CPB