322
FXUS61 KLWX 191402
AFDLWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1002 AM EDT SAT JUL 19 2025
SYNOPSIS
SHOWER AND THUNDERSTORM CHANCES CONTINUE THROUGH THE WEEKEND
TODAY AS A WARM FRONT SLOWLY LIFTS NORTH OF THE REGION TODAY. A
COLD FRONT FOLLOWS SUNDAY NIGHT. LESS HUMIDITY AND DRIER
CONDITIONS TO START NEXT WEEK AS CANADIAN HIGH PRESSURE BUILDS
IN. HEAT AND HUMIDITY RETURN LATE NEXT WEEK.
NEAR TERM /THROUGH TONIGHT/
A FRONTAL BOUNDARY REMAINS STALLED ACROSS THE AREA THIS MORNING,
GENERALLY ARCING ALONG I-66 OUT TOWARD THE EASTERN SHORE. A
BROAD AREA OF STRATUS REMAIN OVER THE AREA, ALTHOUGH SOME BREAKS
ARE NOTED DOWN TOWARD THE I-64 CORRIDOR. THERE IS CERTAINLY
PLENTY OF MOISTURE IN THE ATMOSPHERE WITH THE 12Z IAD SOUNDING
DEPICTING A PRECIPITABLE WATER VALUE OF 2.08 INCHES. PER THE
STORM PREDICTION CENTER SOUNDING CLIMATOLOGY, THIS VALUE RUNS
FAIRLY CLOSE TO THE DAILY MAXIMA.
ON RADAR, SOME ACTIVITY REMAINS AROUND THE NORTHERN CHESAPEAKE
BAY. FURTHER UPSTREAM, A CLUSTER OF SHOWERS AND THUNDERSTORMS IS
CURRENTLY SWINGING EASTWARD NEAR ELKINS, WEST VIRGINIA. EXPECT
THIS TO BRING SOME RESIDUAL THUNDER CHANCES ACROSS PENDLETON AND
GRANT COUNTIES IN THE NEXT HOUR OR SO.
THE MENTIONED FRONT EVENTUALLY LIFTS NORTH OF THE AREA LATER
TODAY AS A WARM FRONT AS A LIGHT SOUTH WIND DEVELOPS. THE
WIDESPREAD CLOUDS ONCE AGAIN KEEP HIGHS IN THE MID TO UPPER 80S.
HEAT INDICES BETWEEN 90-100 EAST OF THE BLUE RIDGE.
CONVECTION IS ONCE AGAIN EXPECTED DURING THE AFTERNOON TO EVENING
HOURS, WITH THE HIGHEST COVERAGE MOST LIKELY FROM THE CENTRAL
SHENANDOAH VALLEY TO CENTRAL VIRGINIA. MUCH LIKE YESTERDAY, ABUNDANT
INSTABILITY AND WEAK SHEAR WILL HELP SUPPORT SOME BETTER ORGANIZED
CLUSTERS OF THUNDERSTORMS.
AS STORMS ARE SLIGHTLY BETTER SETUP TODAY, THERE IS GOING TO BE A
RISK FOR A FEW SEVERE THUNDERSTORMS, WITH DAMAGING WINDS AS THE
PRIMARY THREAT. SPC HAS UPGRADED TO A SLIGHT RISK (LEVEL 2 OF 5)
ACROSS CENTRAL VA, WITH A MARGINAL RISK (LEVEL 1 OF 5) ELSEWHERE.
BASED ON THE LATEST CAMS (FOR WHAT IT'S WORTH) IT APPEARS THE
GREATEST CHANCE FOR SEVERE IS SOUTH OF I-66 AND EAST OF THE BLUE
RIDGE.
STORMS ARE ALSO GOING TO BE CAPABLE OF PRODUCING ISOLATED TO
SCATTERED INSTANCES OF FLOODING. GIVEN THE SIGNAL FOR A SECOND DAY
OF HEAVY RAINFALL IN CENTRAL VA, A FLOOD WATCH HAS BEEN ISSUED FROM
2PM TO 10PM TODAY.
SHOWER AND THUNDERSTORM ACTIVITY WINDS DOWN IN THE EVENING, THOUGH
SHOWERS COULD CONTINUE IN THE ALLEGHENIES THROUGH THE NIGHT. WARM
AND MUGGY AS LOWS SETTLE IN THE 70S.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/
A WEAK SHORTWAVE TROUGH ALOFT MOVES THROUGH EARLY SUNDAY MORNING.
DEEP WESTERLY FLOW DEVELOPS IN ITS WAKE, THOUGH WE REMAIN IN A HOT
AND HUMID AIRMASS THROUGH SUNDAY NIGHT WHEN A STRONG COLD FRONT
MOVES THROUGH. HIGHS SUNDAY REACH THE LOW TO MID 90S, WITH HEAT
INDICES AROUND 98-104. SCATTERED SHOWERS AND THUNDERSTORMS ARE
FORECAST TO DEVELOP IN THE AFTERNOON TO EVENING, THOUGH IT REMAINS
TO BE SEEN HOW EXPANSIVE COVERAGE OF STORMS IS IN THE PREDOMINANT
WESTERLY FLOW. THERE WILL BE PLENTY OF INSTABILITY AND MODEST SHEAR,
SO A FEW SEVERE THUNDERSTORMS ARE POSSIBLE. SPC HAS MAINTAINED THE
ENTIRE AREA IN A MARGINAL RISK (LEVEL 1 OF 5). THE FLOOD RISK WILL
BE LOWER GIVEN BETTER STORM MOTION, BUT WITH SATURATED GROUND IN
MANY AREAS IT WON'T TAKE MUCH TO CAUSE FLOODING.
A MASSIVE PATTERN CHANGE TO START NEXT WEEK AS CANADIAN HIGH
PRESSURE BUILDS IN FROM THE NORTH. WHILE SOME RESIDUAL MOISTURE
COULD FIRE UP FEW SHOWERS/THUNDERSTORMS IN THE ALLEGHENIES MONDAY
AFTERNOON, MOST OF THE AREA LOOKS TO BE DRY. HIGHS IN THE LOW TO MID
80S AND MUCH LESS HUMIDITY. EVEN DRIER AIR FILTERS IN MONDAY NIGHT
AND ALLOWS TEMPS TO DROP TO THE LOW/MID 60S (50S POSSIBLE FOR
SOME).
LONG TERM /TUESDAY THROUGH FRIDAY/
THE BRIEF REPRIEVE FROM THE HIGH HEAT AND HUMIDITY CONTINUES TUESDAY
AS CANADIAN HIGH PRESSURE DRIFTS ACROSS INTERIOR NEW ENGLAND AND
TOWARD THE COAST. HIGH TEMPERATURES WILL ONCE AGAIN TOP OUT IN THE
UPPER 70S AND LOW TO MID 80S WITH DEWPOINTS IN THE UPPER 50S AND MID
60S. OVERNIGHT LOWS WILL RANGE FROM THE UPPER 50S WEST OF THE BLUE
RIDGE TO LOW AND MID 60S FURTHER EAST. A FEW PASSING SHOWERS ARE
POSSIBLE OVER THE POTOMAC HIGHLANDS AND CENTRAL SHENANDAOH VALLEY
TUESDAY AFTERNOON AND EVENING AS A WEAK PIECE OF SHORTWAVE ENERGY
RIPPLES THROUGH. OVERALL CONFIDENCE AMONGST CURRENT SYNOPTIC AND
ENSEMBLE GUIDANCE REMAINS LOW SO CAPPED POPS BETWEEN 15-20 PERCENT
WITH A FOCUS SOUTH OF A LINE EXTENDING FROM BAYARD,WV DOWN TOWARD
CHARLOTTESVILLE, VA. MOST WILL SEE ANOTHER DRY DAY WITH PARTLY
CLOUDY TO MOSTLY SUNNY SKIES EXPECTED.
BY WEDNESDAY, HIGH PRESSURE SHIFTS OFF THE NEW ENGLAND COAST.
HUMIDITY WILL GRADUALLY RETURN UNDER LIGHT SOUTHEASTERLY FLOW.
DEWPOINTS WILL CLIMB BACK INTO THE UPPER 60S AND LOW 70S WITH HIGH
TEMPERATURES PUSHING BACK TOWARD 90 DEGREES. MEANWHILE, BROAD UPPER
LEVEL RIDGING OVER THE SOUTH-CENTRAL U.S WILL GRADUALLY EXPAND NORTH
AND EAST TOWARD THE MID-ATLANTIC ALLOWING FOR MORE HAT AND HUMIDITY
TO BUILD LATER IN THE WORKWEEK. HIGHS THURSDAY AND FRIDAY WILL PUSH
BACK INTO THE LOW TO MID 90S WITH HEAT INDEX VALUES UP AROUND 100
DEGREES.SHOWER AND THUNDERSTORM CHANCES ALSO RETURN DURING THIS AS A
SLOW MOVING COLD FRONT SAGS INTO THE REGION. HIGHEST CHANCES FOR
THUNDERSTORMS LOOK TO BE FRIDAY INTO THE UPCOMING WEEKEND AS THE
FRONT INCHES CLOSER TO THE REGION.
AVIATION /14Z SATURDAY THROUGH WEDNESDAY/
GIVEN THE DEGREE OF LOW-LEVEL MOISTURE AND LIGHT WINDS, LOW
CEILINGS HAVE BEEN STUBBORN TO ERODE THIS MORNING. IN REPSONSE,
HAVE KEPT RESTRICTIONS IN FOR MOST TAF SITES THROUGH 11 AM THIS
MORNING. EXPECT DAYTIME HEATING TO EVENTUALLY MIX THESE LOW
CLOUDS OUT WITH A RETURN TO VFR CONDITIONS LIKELY BY NOON.
AFTERNOON SHOWERS AND THUNDERSTORMS FOCUS AT CHO, WITH PROB30 GROUPS
AT ALL OTHER TERMINALS FOR A SHORT WINDOW OF IMPACTS. OUTSIDE OF
CONVECTION, VFR CONDITIONS ARE EXPECTED.
A COLD FRONT MOVES THROUGH THE AREA LATE SUNDAY, WITH A FINAL ROUND
OF SHOWERS AND THUNDERSTORMS LIKELY IMPACTING ALL THE TERMINALS IN
THE LATE AFTERNOON TO EVENING. BEHIND THE FRONT, VFR CONDITIONS
EXPECTED SUNDAY NIGHT INTO MONDAY.
PREVAILING VFR CONDITIONS ARE EXPECTED TUESDAY THROUGH FRIDAY. SUB-
VFR REDUCTIONS REMAIN POSSIBLE DURING THE AFTERNOON AND EVENING
HOURS THURSDAY AND FRIDAY AS A RESULT OF SHOWERS AND THUNDERSTORMS.
WINDS WILL REMAIN LIGHT OUT OF THE EAST AND SOUTHEAST TUESDAY BEFORE
TURNING SOUTHERLY MID TO LATE NEXT WEEK AS HIGH PRESSURE PUSHES OFF
THE NEW ENGLAND COAST.
MARINE
LIGHT SOUTHERLY WINDS DEVELOP THROUGH THE DAY, THOUGH MOSTLY AROUND
5-10 KNOTS. A COLD FRONT MOVES THROUGH SUNDAY NIGHT, AND THAT COULD
BRING A PERIOD OF SCA WINDS TO THE OPEN WATERS OF THE CHESAPEAKE
BAY.
DAILY SHOWERS AND THUNDERSTORM CONTINUE THROUGH THE WEEKEND. THE
HIGHEST RAIN CHANCES TODAY FOCUS ALONG THE TIDAL POTOMAC AND SOUTH
OF THE BAY BRIDGE. FOR SUNDAY, CONVECTION LOOKS POSSIBLE ACROSS ALL
THE WATERS. ANY THUNDERSTORM WILL POSE A THREAT TO MARINERS DUE TO
STRONG WIND GUSTS AND LIGHTNING STRIKES. SPECIAL MARINE WARNINGS ARE
LIKELY NEEDED AT TIMES EACH AFTERNOON TO EVENING AS THUNDERSTORMS
MOVE ACROSS THE WATERS.
DRY CONDITIONS AND NORTH WINDS AROUND 10 KNOTS MONDAY INTO MONDAY
NIGHT, AND WINDS SHOULD REMAIN JUST BELOW SCA LEVELS.
SUB-SCA LEVEL WINDS ARE EXPECTED THROUGH WEDNESDAY WITH CANADIAN
HIGH PRESSURE ANCHORED NORTH OF THE WATERS. SOME SOUTHERLY
CHANNELING IS POSSIBLE LATER IN THE WEEK AS WINDS SWITCH BACK TO THE
SOUTH AND SOUTHEAST WITH HIGH PRESSURE PUSHING OFFSHORE.
TIDES/COASTAL FLOODING
LIGHT WINDS ACROSS THE AREA WILL MAINTAIN ELEVATED TIDAL
ANOMALIES. AT THIS POINT, ONLY ANNAPOLIS COULD SEE A RUN AT
MINOR TIDAL FLOODING, MAINLY DURING THE HIGHER OF THE
ASTRONOMICAL TIDES. THESE WILL OCCUR DURING THE MIDDLE OF THE
NIGHT THIS WEEKEND. A STRONG COLD FRONT MOVES THROUGH THE WATERS
LATE SUNDAY WHICH SHOULD HELP LOWER WATER LEVELS INTO NEXT WEEK.
LWX WATCHES/WARNINGS/ADVISORIES
DC...NONE.
MD...NONE.
VA...FLOOD WATCH FROM 2 PM EDT THIS AFTERNOON THROUGH THIS EVENING
FOR VAZ037>040-050-051-055>057-502.
WV...NONE.
MARINE...NONE.
SYNOPSIS...EST
NEAR TERM...BRO/KRR
SHORT TERM...KRR
LONG TERM...EST
AVIATION...BRO/KRR/EST
MARINE...KRR/EST
TIDES/COASTAL FLOODING...BRO
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