275
FXUS61 KLWX 121503
AFDLWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1103 AM EDT FRI JUN 12 2026
WHAT HAS CHANGED
CONFIDENCE IS INCREASING FOR THUNDERSTORMS TO FORM THIS
AFTERNOON ALONG A DEVELOPING SURFACE TROUGH ORIENTED FROM
NORTHEAST TO SOUTHWEST FROM ROUGHLY BALTIMORE TO DC TO
CHARLOTTESVILLE. CONFIDENCE IN STORMS FORMING TO THE NORTHWEST
OF THE THIS DEVELOPING SURFACE TROUGH IS CONSIDERABLY LESS. ANOTHER
ROUND OF THUNDERSTORMS MAY POTENTIALLY FORM TO OUR WEST IN WEST
VIRGINIA AND THEN MOVE ACROSS SOUTHWESTERN PORTIONS OF THE
FORECAST AREA.
KEY MESSAGES
- 1) HOT AND HUMID CONDITIONS PERSIST TODAY WITH ANOTHER ROUND
OF STRONG TO SEVERE THUNDERSTORMS EXPECTED.
- 2) SHOWER AND THUNDERSTORM CHANCES RETURN LATE SUNDAY INTO
NEXT WEEK AS A COLD FRONT MOVES THROUGH THE REGION.
DISCUSSION
KEY MESSAGE 1...HOT AND HUMID CONDITIONS PERSIST TODAY WITH ANOTHER ROUND
OF STRONG TO SEVERE THUNDERSTORMS EXPECTED.
HEAT AND HUMIDITY LINGERS TODAY, AND UNLESS THERE IS A LOT OF
MORNING CLOUD COVER IT LOOKS TO BE A BIT HOTTER. THERE IS THE
POTENTIAL FOR A BIT MORE MIXING DOWN OF LOWER DEW POINTS GIVEN
LINGERING WESTERLY FLOW, BUT HEAT INDEX VALUES LIKELY APPROACH
100 TO 105 AGAIN IN THE AFTERNOON. HAVE EXPANDED THE HEAT
ADVISORY WESTWARD IN COORDINATION WITH NEIGHBORING WFOS.
HOWEVER, AS ALWAYS, JUST BECAUSE AN ADVISORY MAY NOT BE IN
EFFECT FOR ALL AREAS, IT WILL BE VERY HOT/HUMID EITHER WAY, SO
ALL SHOULD TAKE PROPER PRECAUTIONS ONCE AGAIN.
AS OF 10 AM, SKIES ARE SUNNY ACROSS THE FORECAST AREA.
TEMPERATURES ARE CURRENTLY IN THE 80S, AND ARE EXPECTED TO CLIMB
WELL INTO THE 90S THIS AFTERNOON, WITH DEWPOINTS HOLDING IN THE
60S TO LOWER 70S. THIS WILL ALLOW AMPLE INSTABILITY TO BUILD
ACROSS THE FORECAST AREA OVER THE COURSE OF THE DAY. ON THE
SYNOPTIC SCALE, A SHORTWAVE TROUGH ON THE SOUTHEASTERN
PERIPHERY OF A MUCH BROADER CLOSED MID- UPPER LOW LOCATED OVER
CENTRAL CANADA IS CURRENTLY TRACKING OVER THE SOUTHERN GREAT
LAKES AND WILL LIFT NORTHEASTWARD INTO ONTARIO/QUEBEC OVER THE
COURSE OF THE DAY. LOCALLY, A WEAK SURFACE RIDGE IS IN PLACE AT
MID-UPPER LEVELS AT THE MOMENT, BUT GLANCING HEIGHT FALLS ARE
EXPECTED THROUGH THE AFTERNOON AS THAT DISTURBANCE PASSES TO OUR
NORTHWEST. AT THE SURFACE, A COLD FRONT EXTENDS SOUTHWESTWARD
ACROSS LAKE ERIE INTO OHIO AND SOUTHERN INDIANA. THIS BOUNDARY
WILL GRADUALLY PROGRESS SOUTHEASTWARD OVER THE COURSE OF THE
DAY, EVENTUALLY MOVING THROUGH THE AREA LATE THIS AFTERNOON
INTO THIS EVENING. CURRENT SURFACE OBSERVATIONS SHOW WINDS
STARTING TO TURN WESTERLY ACROSS NORTHWESTERN AND NORTH CENTRAL
MARYLAND, AS WELL AS THE WV PANHANDLE, WHILE WINDS FURTHER
SOUTHEAST HOLD OUT OF THE SOUTH TO SOUTHWEST. THIS SUGGESTS THAT
A PREFRONTAL SURFACE TROUGH IS IN THE PROCESS OF DEVELOPING.
THIS PREFRONTAL TROUGH IS EXPECTED TO BECOME ORIENTED FROM
ROUGHLY JUST NORTH AND WEST OF DC/BALTIMORE ALONG THE I-95
CORRIDOR, BEFORE ARCING SOUTHWESTWARD INTO CENTRAL VIRGINIA.
SURFACE CONVERGENCE IS EXPECTED TO BECOME MAXIMIZED WITHIN THIS
SURFACE TROUGH AS THE SOUTH/SOUTHWESTERLIES FURTHER SOUTHEAST
RUN INTO THE WESTERLIES FURTHER NORTHWEST. THIS SURFACE
CONVERGENCE IS EXPECTED TO LEAD TO THE DEVELOPMENT OF
THUNDERSTORMS DURING THE EARLY TO MID-AFTERNOON HOURS IN THE
VICINITY OF THE SURFACE TROUGH. THOSE THUNDERSTORMS WILL THEN
LIKELY PROCEED TO GROW UPSCALE INTO A LINE AND PROGRESS OFF
TOWARD THE EAST. AS A RESULT, CONFIDENCE FOR THUNDERSTORMS TODAY
IS THE HIGHEST ALONG AND SOUTHEAST OF WHERE THIS SURFACE TROUGH
SETS UP (ROUGHLY I-95 SOUTH AND EAST, SOUTHWESTWARD INTO CENTRAL
VIRGINIA). FURTHER NORTHWEST, THE WESTERLY LOW-LEVEL WINDS MAY
BE ABLE TO MIX DOWN LOWER DEWPOINTS, LEADING TO LESSER
INSTABILITY. THERE WILL ALSO BE A LACK OF SURFACE CONVERGENCE
WITHIN THE UNIFORM WESTERLIES. AS A RESULT OF THE LACK OF
SURFACE CONVERGENCE AND GREATER AMOUNT OF LOW- LEVEL DRY AIR,
CONFIDENCE IN THE DEVELOPMENT OF THUNDERSTORMS IS MUCH LOWER TO
THE NORTHWEST OF THIS DEVELOPING SURFACE TROUGH (GEOGRAPHICALLY,
THIS WOULD INCLUDE NORTH CENTRAL MD, WESTERN MD, NORTHWESTERN
VA, AND NORTHERN PORTIONS OF THE WV PANHANDLE). A SECONDARY AREA
OF STORMS MAY ALSO FORM OFF TO OUR WEST OVER CENTRAL WEST
VIRGINIA JUST AHEAD OF THE APPROACHING COLD FRONT. WHILE, WE
CAN'T RULE OUT THESE STORMS FORMING ANYWHERE NORTH TO SOUTH
ACROSS WEST VIRGINIA, GUIDANCE SUGGESTS THAT CHANCES WILL BE
GREATER WITH SOUTHWARD EXTENT. THIS ACTIVITY WOULD THEN LIKELY
PROPAGATE OVER THE MOUNTAINS INTO OUR AREA LATER THIS AFTERNOON
AS A COLD POOL BECOMES ESTABLISHED. ANY STORMS THAT FORM SHOULD
MOVE OUT OF THE FORECAST AREA LATER THIS EVENING AS THE COLD
FRONT MOVES THROUGH AND DRIER AIR STARTS TO ADVECT IN FROM THE
WEST.
WITH A HIGH CAPE/HIGH DCAPE ENVIRONMENT IN PLACE TODAY, ANY
STORMS SHOULD BE EFFICIENT PRODUCERS OF DAMAGING WINDS, WITH
WIND GUSTS OF 60-70 MPH POSSIBLE IN STRONGER STORMS. SPC HAS
NEARLY ALL OF THE FORECAST AREA (THE EXCEPTION BEING GARRETT
COUNTY) OUTLOOKED IN A SLIGHT RISK FOR SEVERE THUNDERSTORMS,
WITH DAMAGING WINDS BEING THE PRIMARY THREAT. AN ISOLATED
INSTANCE OR TWO OF LARGE HAIL CAN'T BE RULED OUT, BUT THE VERY
HOT AIRMASS IN PLACE AND LACK OF DEEPER LAYER SHEAR SHOULD LIMIT
HAIL PRODUCTION FOR THE MOST PART.
FOLLOWING THE COLD FRONTAL PASSAGE TONIGHT, HIGH PRESSURE WILL
BRIEFLY PIVOT OVER THE MID-ATLANTIC SATURDAY. THIS RESULTS IN
NOTABLY LOWER HUMIDITY AND TEMPERATURES SEVERAL DEGREES COOLER
(RELATIVELY SPEAKING) AS WELL.
MORE SUN THAN CLOUDS AMID LIGHT NORTHWEST BREEZES ARE EXPECTED.
TEMPERATURES FALLING INTO THE 60S SATURDAY NIGHT WITH DEW POINTS
AROUND 60 WILL FEEL LIKE A STARK CONTRAST TO THE MORE OPPRESSIVE
HUMIDITY IN THE PRECEDING COUPLE OF DAYS/NIGHTS.
KEY MESSAGE 2...SHOWER AND THUNDERSTORM CHANCES RETURN LATE
SUNDAY INTO NEXT WEEK AS A COLD FRONT MOVES THROUGH THE REGION.
A DEEP UPPER-LEVEL TROUGH WILL FORM OVER THE GREAT LAKES TOWARDS THE
END OF THE WEEKEND, RESULTING IN A COLD FRONT THAT WILL TRACK
THROUGH THE EAST COAST BETWEEN LATE SUNDAY AND GOING INTO MONDAY.
APPEARS TO BE ENOUGH SHEAR AND FORCING, MAIN QUESTION SUNDAY IS
THE INSTABILITY. LATEST GUIDANCE HAS THE HIGHER INSTABILITY SE
OF THE LOCAL FA. STILL A FEW DAYS OUT, A LOT CAN CHANGE WITH
CONVECTION AT THIS JUNCTURE.
ONCE THIS COLD FRONT MOVES THROUGH, WE COULD BEGIN TO SEE A BRIEF
DIP IN TEMPERATURES, WITH HIGHS FOR MONDAY CURRENTLY RANGING LARGELY
IN THE 80S. ALTHOUGH THE LOW PRESSURE SYSTEM ASSOCIATED WITH THIS
FRONT WILL PUSH NORTH BY LATE MONDAY, ANOTHER AREA OF LOW PRESSURE
COULD BUILD TOWARDS THE SOUTH AND PUSH NORTH ON TUESDAY, BRINGING
ADDITIONAL CHANCES FOR RAIN AND SHOWERS. BY THIS POINT, SEVERE
CHANCES BECOME MUCH MORE UNCERTAIN AS INSTABILITY LOOKS RATHER WEAK,
BUT OVERALL EXPECT A REPEATING PATTERN OF FRONTAL BOUNDARIES
TRACKING THROUGH THE REGION BRINGING SEVERAL OPPORTUNITIES FOR
PRECIPITATION.
AVIATION /14Z FRIDAY THROUGH TUESDAY/
PREVAILING VFR CONDITIONS ARE EXPECTED THROUGH THIS EVENING.
HAVE MAINTAINED PROB30 FOR THE THUNDERSTORM POTENTIAL THIS
AFTERNOON. WILL MONITOR FUTURE TRENDS AND MAY EVENTUALLY NEED TO
CATEGORICALLY ADD THUNDERSTORMS INTO THE TAFS.
WINDS WILL BE FAIRLY LIGHT OUT OF THE WEST OR SOUTHWEST BOTH
DAYS OUTSIDE OF ANY STORMS.
VFR CONDITIONS ARE PREDOMINANTLY EXPECTED THROUGH THE WEEKEND, WITH
SOME REDUCED CONDITIONS POSSIBLE BEGINNING SUNDAY EVENING ASSOCIATED
WITH A LOW CHANCE OF SHOWERS AND THUNDERSTORMS. PERIODICALLY REDUCED
CONDITIONS ASSOCIATED WITH A LOW PRESSURE SYSTEM COULD CONTINUE
THROUGH EARLY NEXT WEEK. GUSTS BETWEEN 15-20 KNOTS ARE POSSIBLE
SUNDAY EVENING BEFORE FALLING AGAIN MONDAY, WITH SOUTHWEST WINDS
SHIFTING EASTERLY BY MONDAY EVENING.
MARINE
GENERALLY LIGHT WEST TO SOUTHWEST WINDS ARE EXPECTED THROUGH
TODAY, BECOMING NORTHWEST TONIGHT THROUGH SATURDAY. THERE IS A
POTENTIAL OF AT LEAST BRIEF NEAR SCA CONDITIONS BEHIND A COLD
FRONT TONIGHT INTO SATURDAY MORNING, THOUGH THE THREAT HAS
DECREASED SOMEWHAT. AHEAD OF THIS FRONT, POTENTIAL SHOWERS AND
THUNDERSTORMS BRING A RISK OF LIGHTNING AND STRONG WINDS TO THE
WATERS ON THIS AFTERNOON/EVENING. THIS WILL LIKELY SUPPORT THE
NEED OF SPECIAL MARINE WARNINGS, WITH 50+ KNOT WINDS POSSIBLE IN
ANY STORMS.
SCAS WILL LIKELY BE NEEDED SUNDAY EVENING WITH GUSTS UP TO 20 KNOTS
POSSIBLE, BUT SHOULD GO BACK BELOW SCA THRESHOLDS BY MONDAY MORNING.
SOUTHWEST WINDS SHIFT NORTHERLY MONDAY AFTERNOON BEFORE SHIFTING
SOUTHEAST.
CLIMATE
TEMPERATURES ARE EXPECTED TO SOAR TO AS MUCH AS 15 TO 20 DEGREES
ABOVE AVERAGE TODAY. THIS APPROACHES OR EXCEEDS DAILY RECORD
VALUES AT SOME SITES.
BELOW IS A LIST OF RECORD DAILY HIGH AND WARM LOW TEMPERATURES
FOR TODAY (JUNE 12TH).
=================================================================
JUNE 12TH RECORD DAILY HIGHS AND WARM LOWS
=================================================================
SITE RECORD HIGH RECORD WARM LOW
DCA 95 F (SET IN 2017 +6 OTHERS) 77 F (SET IN 2015)
IAD 96 F (SET IN 1986) 72 F (SET IN 1986)
BWI 96 F (SET IN 1986 AND 1914) 77 F (SET IN 1947)
DMH 96 F (SET IN 2025 +2 OTHERS) 77 F (SET IN 2017 AND 2015)
NAK 98 F (SET IN 1914) 77 F (SET IN 2000 AND 1973)
HGR 92 F (SET IN 2017 +5 OTHERS) 71 F (SET IN 2010 +5 OTHERS)
MRB 97 F (SET IN 1938 AND 1933) 73 F (SET IN 1914)
CHO 98 F (SET IN 1914) 72 F (SET IN 1947 +2 OTHERS)
LWX WATCHES/WARNINGS/ADVISORIES
DC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR DCZ001.
MD...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR MDZ003>006-008-
011-013-014-016>018-503>508.
VA...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR VAZ025>031-
036>040-050-051-053>057-501-502-505-506-526-527.
WV...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR WVZ051>053.
MARINE...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ530.
DISCUSSION...KJP/CPB/SRT
AVIATION...CJL/CPB/SRT
MARINE...CJL/CPB/SRT
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