319
FXUS61 KLWX 171405
AFDLWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1005 AM EDT SUN MAY 17 2026
WHAT HAS CHANGED
MADE SOME SIGNIFICANT CHANGES TO THE POPS AND WEATHER FORECAST
THIS MORNING TO REFLECT SHOWER CHANCES ASSOCIATED WITH A PASSING
REMNANT MCV. NOTHING HAZARDOUS THIS MORNING, BUT JUST HAD TO
BRING UP RAIN CHANCES FOR THE NORTHERN HALF OF THE FORECAST
AREA.
KEY MESSAGES
- 1) FEELING MORE LIKE SUMMER WITH NEAR RECORD BREAKING TEMPS
AND DAILY SHOWER AND THUNDERSTORM CHANCES THROUGH TUESDAY.
- 2) A STRONG COLD FRONT MOVES THROUGH ON WEDNESDAY, BRINGING
CHANCES FOR THUNDERSTORMS. MUCH COOLER AND SHOWERY CONDITIONS
ARE EXPECTED TO END THE WEEK.
DISCUSSION
KEY MESSAGE 1... FEELING MORE LIKE SUMMER WITH NEAR RECORD BREAKING
TEMPS AND DAILY SHOWER AND THUNDERSTORM CHANCES THROUGH TUESDAY.
STILL TRACKING SOME SHOWER ACTIVITY ALONG THE LEADING EDGE OF A
DECAYING MCV MOVING ACROSS THE REGION AS OF 10 AM THIS MORNING.
SHOWER ACTIVITY, AND THUS CLOUDCOVER, WAS HIGHER THAN
ORIGINALLY ANTICIPATED, SO BUMPED THAT UP WITH THE MORNING
FORECAST PACKAGE. ALSO, BUMPED UP THE POPS THIS AFTERNOON INTO
THE "SCATTERED" CATEGORY. COULD STILL SEE THIS GOING EITHER WAY,
BUT LATEST HI-RES GUIDANCE ALL HAS AT LEAST SOME MINIMAL
CONVECTIVE DEVELOPMENT AFTER 1-2 PM, SO WANTED TO BUMP THINGS UP
A BIT.
PREVIOUS DISCUSSION: THE REMNANT MCV FEATURE WILL CROSS THE
REGION LATE MORNING INTO MIDDAY LEADING TO ADDITIONAL SPOTTY
SHOWER AND T-STORM CHANCES, ESPECIALLY IN AREAS ALONG AND NORTH
OF I-66/US-50. 00Z CAMS REMAIN ALL OVER THE PLACE WHEN IT COMES
TO COVERAGE AND TIMING GIVEN THE STRENGTHENING HIGH OFFSHORE AND
MORNING CONVECTIVE DEBRIS WHICH COULD DAMPEN ADDITIONAL
SHOWER/THUNDERSTORM DEVELOPMENT. WITH ZONAL FLOW IN PLACE ANY
ADDITIONAL WAVES OF ENERGY EJECTING FROM WEST TO EAST OUT OF THE
OHIO/MS RIVER VALLEY COULD TOUCH OFF A SHOWER OR T-STORM GIVEN
THE INCREASED HEAT AND HUMIDITY. ONCE AGAIN CONFIDENCE IS LOW
GIVEN WEST TO NORTHWEST DOWNSLOPING FLOW EAST OF THE MOUNTAINS
WHICH WOULD MAKE FOR A MORE HIT OR MISS TYPE OF ENVIRONMENT. ANY
STORMS THAT WE DO SEE TODAY COULD PUT DOWN LOCALLY GUSTY WINDS,
BRIEF HEAVY RAINFALL, AND FREQUENT LIGHTNING. EXPECT A SIMILAR
SETUP MONDAY AND TUESDAY ALTHOUGH THE COVERAGE OF STORMS WILL BE
FURTHER REDUCED AS UPPER LEVEL RIDGING CONTINUES TO STRENGTHEN
EAST OF THE REGION. SHOWERS AND T-STORMS WILL BE CONFINED TO THE
MOUNTAINS DUE TO TERRAIN INFLUENCES AND A LACK OF LIFTING
MECHANISM.
OUTSIDE OF THE AFTERNOON/EVENING SHOWER AND THUNDERSTORM THREAT WILL
BE THE BIGGER STORY WHICH IS THE HEAT. DID CUT BACK HIGHS A LITTLE
BIT TODAY DUE TO ADDED MID AND HIGH LEVEL CLOUD COVER. MOST
LOCATIONS WILL PUSH INTO THE MID TO UPPER 80S WITH UPPER 70S OVER
THE MOUNTAINS. LOCATIONS SOUTH AND EAST OF DC/BALTIMORE COULD PUSH
TOWARD 90 DEGREES WITH MORE SUNSHINE. THE BIGGER HEAT BUILDS INTO
THE AREA MONDAY AND TUESDAY WITH WIDESPREAD HIGHS IN THE LOW TO MID
90S. TUESDAY WILL MARK THE HOTTEST DAY OF THE NEXT 7 WITH HIGHS IN
THE MID TO UPPER 90S EAST OF THE MOUNTAINS. HUMIDITY WILL GRADUALLY
INCREASE AS WELL ALTHOUGH NOT TO THE EXTENT WHERE HEAT HEADLINES
WILL BE NEEDED. SOMETHING THAT WE'LL CONTINUE TO MONITOR SINCE WE
ARE EARLY IN THE SEASON. DON'T EXPECT TOO MUCH RELIEF FROM THE HEAT
AT NIGHT WITH LOW TEMPERATURES MONDAY AND TUESDAY NIGHTS IN THE MID
60S AND LOW 70S.
KEY MESSAGE 2...A STRONG COLD FRONT MOVES THROUGH ON WEDNESDAY,
BRINGING CHANCES FOR THUNDERSTORMS. MUCH COOLER AND SHOWERY
CONDITIONS ARE EXPECTED TO END THE WEEK.
THE STRONG UPPER RIDGE OVERHEAD WILL FINALLY BREAK DOWN ON WEDNESDAY
AS A LARGE TROUGH TRACKS EASTWARD ACROSS ONTARIO AND QUEBEC. A
STRONG COLD FRONT ASSOCIATED WITH THIS SYSTEM WILL TRACK
SOUTHEASTWARD ACROSS THE GREAT LAKES AND OHIO VALLEY OVER THE COURSE
OF THE DAY. HEAT AND HUMIDITY WILL REMAIN IN PLACE IN ADVANCE OF THE
FRONT, WITH DEWPOINTS HOLDING IN THE 60S AND TEMPERATURES FORECAST
TO CLIMB INTO THE MID 90S AT LOWER ELEVATIONS ONCE AGAIN. SHOWERS
AND THUNDERSTORMS ARE EXPECTED TO FORM ACROSS THE AREA IN ADVANCE OF
THE FRONT WEDNESDAY AFTERNOON. THE STRONGEST WINDS AT MID TO UPPER
LEVELS LOOK LIKE THEY WILL PASS TO OUR NORTH, SO SHEAR WON'T BE
OVERLY IMPRESSIVE. HOWEVER, A FEW STRONGER STORMS CAN'T BE RULED OUT
WITH AMPLE INSTABILITY IN PLACE.
THE FRONT WILL PUSH THROUGH OUR AREA WEDNESDAY NIGHT AS STRONG HIGH
PRESSURE BUILDS TO OUR NORTH OVER THE GREAT LAKES. NORTHERLY WINDS
WILL ADVECT A MUCH COOLER AIRMASS INTO THE REGION FOR THURSDAY, WITH
TEMPERATURES ONLY FORECAST TO MAKE IT INTO THE LOWER 70S. THE HIGH
WILL THEN SHIFT OFF TO OUR NORTHEAST FOR FRIDAY AND SATURDAY,
CAUSING WINDS TO TURN OUT OF THE EAST. MEANWHILE, WEAK TROUGHING AT
MID-UPPER LEVELS IS EXPECTED TO BECOME ESTABLISHED ACROSS THE
MISSISSIPPI AND TENNESSEE VALLEYS, PLACING US IN SOUTHWESTERLY FLOW
ALOFT. THIS WILL RESULT IN A PATTERN WHERE WARM ADVECTION ENSUES
ALOFT ATOP THE ONSHORE FLOW. CLOUDY AND SHOWERY CONDITIONS WILL BE
THE RESULT FOR THURSDAY, AND ESPECIALLY FOR FRIDAY AND SATURDAY.
WHILE THE PATTERN DOESN'T LOOK OVERLY FAVORABLE FOR THUNDERSTORMS,
RAIN FROM THE FREQUENT SHOWERS SHOULD ADD UP, WITH ENSEMBLE MEAN
RAINFALL TOTALS FOR THE WEDNESDAY THROUGH SATURDAY PERIOD GENERALLY
BETWEEN ONE AND TWO INCHES ACROSS THE ENTIRE FORECAST AREA. IF THIS
SOLUTION WERE TO VERIFY, IT COULD PROVIDE SOME MUCH NEEDED DROUGHT
RELIEF TO THE REGION.
AVIATION /13Z SUNDAY THROUGH THURSDAY/
A FEW SPOTTY LIGHT SHOWERS/DRIZZLE MAY IMPACT THE TERMINALS
THIS MORNING, BUT SHOULD NOT LEAD TO ANY SIGNIFICANT
RESTRICTIONS. CIGS HAVE BEEN KEEPING AROUND 5 KFT, WITH VSBYS
GENERALLY NOT BEING REDUCED BELOW 5-6 SM. CAN'T RULE OUT A
THUNDERSTORM LATER THIS AFTERNOON, SO HAVE PROB30S IN THE LATEST
TAFS TO REFLECT THAT THREAT. CONFIDENCE IS VERY LOW THAT ANY
STORM WILL HIT A TERMINAL, BUT THINK THERE WILL AT LEAST BE A
FEW STORMS OUT THERE THIS AFTERNOON.
PREVAILING VFR CONDITIONS ARE EXPECTED ACROSS THE TERMINALS
THROUGH TUESDAY AS HIGH PRESSURE STRENGTHENS OFFSHORE. LIGHT AND
VARIABLE WINDS THIS MORNING WILL TURN WESTERLY THIS AFTERNOON
AT LESS THAN 10 KTS. SOUTH/SOUTHWESTERLY WINDS RETURN MONDAY AND
TUESDAY GUSTING BETWEEN 15 TO 20 KTS DURING THE AFTERNOON AND
EVENING HOURS. DAILY SHOWER AND THUNDERSTORM CHANCES WILL OCCUR
EACH AFTERNOON ALTHOUGH COVERAGE WILL BE SPOTTY IN NATURE
BETWEEN THE TERMINALS. THE HIGHEST CONFIDENCE FOR SHOWERS AND
T-STORMS APPEARS TO BE WEST OF MRB, HGR, AND FDK. WHERE BRIEF
REDUCTIONS ARE POSSIBLE. ELSEWHERE CONFIDENCE REMAINS LOW GIVEN
THE LACK OF A LIFTING MECHANISM.
PREVAILING VFR CONDITIONS ARE EXPECTED ON WEDNESDAY, BUT TEMPORARY
DROPS TO SUB-VFR CONDITIONS MAY BE POSSIBLE DURING THUNDERSTORMS.
RESTRICTIONS MAY ALSO BE POSSIBLE AT TIMES DURING SHOWERS ON
THURSDAY. WINDS WILL BE OUT OF THE SOUTHWEST ON WEDNESDAY, BEFORE
TURNING OUT OF THE NORTH ON THURSDAY.
MARINE
SUB-SCA LEVEL WINDS ARE EXPECTED TODAY THROUGH MONDAY, ALTHOUGH
OCCASIONAL GUSTS UP TO SCA LEVELS ARE POSSIBLE IN CHANNELING,
ESPECIALLY OVER THE OPEN WATERS DURING THIS AFOREMENTIONED TIME.
LIGHT AND VARIABLE WINDS TODAY WILL SWITCH TO THE WEST THIS
AFTERNOON AT LESS THAN 10 KTS. SOUTH SOUTHEASTERLY WINDS RETURN
MONDAY WITH GUSTS UP TO 20S ACROSS THE BAY AND LOWER TIDAL
POTOMAC. ADDITIONAL SCAS MAY BE NEEDED DUE CHANNELING TUESDAY
INTO TUESDAY NIGHT ESPECIALLY OVER THE WIDER WATERS. WINDS WILL
CONTINUE OUT OF THE SOUTH AND SOUTHWEST WITH GUSTS UP TO 20 KTS.
WINDS MAY NEAR LOW-END SCA LEVELS IN SOUTH TO SOUTHWESTERLY FLOW ON
WEDNESDAY, AND THEN AGAIN IN NORTHERLY FLOW ON THURSDAY. SMWS APPEAR
POSSIBLE WEDNESDAY INTO WEDNESDAY NIGHT AS THUNDERSTORMS MOVE OVER
THE WATERS.
CLIMATE
HERE ARE SOME DAILY TEMPERATURE RECORDS DURING THE MAY 18-20,
2026 TIMEFRAME:
A '+' SIGN INDICATES MULTIPLE YEARS CURRENTLY HOLD THAT RECORD.
A '!' SIGN INDICATES THE RECORD IS FORECAST TO BE TIED OR BROKEN.
***MONDAY, MAY 18TH, 2026***
LOCATION RECORD HIGH (YEAR) RECORD WARM LOW (YEAR)
WASHINGTON-NATIONAL (DCA) 96F (1877) 72F (2015)
WASHINGTON-DULLES (IAD) 91F (1987)! 68F (2015)!
BALTIMORE (BWI) 97F (1962) 70F (2017)
BALTIMORE INNER HARBOR (DMH) 97F (1962) 75F (2017)
MARTINSBURG (MRB) 96F (1911) 66F (2015)!
CHARLOTTESVILLE (CHO) 95F (1962)+ 73F (1911)
ANNAPOLIS (NAK) 95F (1962)+ 69F (1953)+!
HAGERSTOWN (HGR) 93F (1962) 71F (2017)
***TUESDAY, MAY 19TH, 2026***
LOCATION RECORD HIGH (YEAR) RECORD WARM LOW (YEAR)
WASHINGTON-NATIONAL (DCA) 96F (1997)+ 72F (2015)!
WASHINGTON-DULLES (IAD) 92F (1997)+! 66F (2017)+!
BALTIMORE (BWI) 98F (1962) 75F (1877)
BALTIMORE INNER HARBOR (DMH) 98F (1962) 78F (1962)
MARTINSBURG (MRB) 98F (1911) 69F (1996)!
CHARLOTTESVILLE (CHO) 97F (1962) 72F (1997)
ANNAPOLIS (NAK) 96F (1962) 71F (1911)!
HAGERSTOWN (HGR) 97F (1996) 69F (2017)+!
***WEDNESDAY, MAY 20TH, 2026***
LOCATION RECORD HIGH (YEAR) RECORD WARM LOW (YEAR)
WASHINGTON-NATIONAL (DCA) 96F (1996) 73F (2019)
WASHINGTON-DULLES (IAD) 93F (1996) 69F (2019)
BALTIMORE (BWI) 95F (1962) 71F (2019)+
BALTIMORE INNER HARBOR (DMH) 97F (1962) 74F (1998)+
MARTINSBURG (MRB) 97F (1911) 70F (1998)
CHARLOTTESVILLE (CHO) 96F (1996) 73F (1996)
ANNAPOLIS (NAK) 98F (1997) 76F (1898)
HAGERSTOWN (HGR) 97F (1996) 66F (1998)
LWX WATCHES/WARNINGS/ADVISORIES
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.
DISCUSSION...BRO/CJL/KJP/EST
AVIATION...CJL/KJP/EST
MARINE...CJL/KJP/EST
CLIMATE...BRO
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