863
FXUS61 KLWX 221600
AFDLWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1200 PM EDT TUE JUL 22 2025
SYNOPSIS
CANADIAN HIGH PRESSURE MAINTAINS DRY CONDITIONS WITH LOWER HUMIDITY
THROUGH THE MIDDLE OF THE WEEK. A RETURN TO HOT AND HUMID SUMMERTIME
CONDITIONS IS EXPECTED BY LATE THIS WEEK.
NEAR TERM /THROUGH TONIGHT/
A SHALLOW DIURNAL CU FIELD DOTS THE LANDSCAPE NEAR THE
APPALACHIANS DOWN INTO CENTRAL VA AS OF MIDDAY. GIVEN AMPLE DRY
AIR AND SUBSIDENCE ALOFT, IT IS UNLIKELY ANY OF THESE CLOUDS
GAIN ENOUGH DEPTH FOR RAIN. HAVE THEREFORE LEFT A DRY FORECAST,
DESPITE A FEW HI-RES MODELS SHOWING A POP UP SHOWER OR TWO IN
THE VICINITY OF HIGHLAND COUNTY VA THIS EVENING.
OTHERWISE, CANADIAN HIGH PRESSURE CENTERED OVER NY TO SOUTHERN
NEW ENGLAND MAINTAINS DRY CONDITIONS ACROSS OUR AREA. SEASONABLE
HIGH TEMPERATURES ARE EXPECTED THIS AFTERNOON IN THE LOW TO MID
80S WITH ABUNDANT SUNSHINE. UNSEASONABLY DRY AIR IS ADVECTING
IN, LIKELY DROPPING DEW POINTS TO THE 50S ACROSS A GOOD PORTION
OF THE AREA. LOWS TONIGHT WILL BE IN THE 60S. LIGHT ONSHORE FLOW
MAY BRING IN SOME LOW CLOUDS EAST OF THE BLUE RIDGE LATER TONIGHT,
WITH SOME PATCHY FOG POSSIBLE MAINLY WEST OF I-95. A FEW PIECES
OF HI-RES GUIDANCE HAVE SPOTTY SHOWERS LATE TONIGHT OVER NE MD,
THOUGH GIVEN SHALLOW MOISTURE IT'S UNLIKELY MUCH MORE THAN
SPRINKLES ARE OBSERVED.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/
THE CANADIAN HIGH SLIDES OFFSHORE THROUGH THE MIDDLE OF THE
WEEK. DRY CONDITIONS PERSIST OVER THE MID-ATLANTIC AS WINDS TURN
SOUTHEAST THEN SOUTH. TEMPERATURES STEADILY INCREASE EACH DAY,
REACHING THE UPPER 80S WEDNESDAY AND LOW 90S ON THURSDAY.
HUMIDITY SLOWLY STARTS TO INCREASE DURING THIS TIME, THOUGH
STILL WELL BELOW WHAT WE EXPERIENCED FOR THE PAST SEVERAL WEEKS.
OVERNIGHT LOWS IN THE 60S, THOUGH TURNING NOTICEABLY MUGGIER
THURSDAY NIGHT AS TEMPS SETTLE IN THE 70S ON A WARM SOUTHERLY
BREEZE.
LONG TERM /FRIDAY THROUGH MONDAY/
AFTER A REPRIEVE FROM THE PERSISTENT HEAT AND HUMIDITY, THE EXTENDED
PERIOD OF THE FORECAST CONSISTS OF SUMMERTIME CONDITIONS OVER THE
AREA. WHILE THE UPPER RIDGE CENTERED OVER THE FOUR CORNERS EASTWARD
TO THE SOUTHEASTERN U.S. FLATTENS SOME, THE TROPOSPHERE WILL BE
PLENTY WARM TO SUPPORT A RETURN TO ABOVE AVERAGE TEMPERATURES. WHILE
THERE IS SOME UNCERTAINTY IN THE FORECAST, FRIDAY'S HIGHS LIKELY
RETURN TO THE MID/UPPER 90S, COUPLED WITH AMPLE HUMIDITY. DEPENDING
ON WHETHER THE HIGHER DEW POINTS IN THE MORNING CAN HOLD ON INTO THE
CORE HEATING HOURS, THERE WILL BE THE POTENTIAL FOR SOME HEAT
ADVISORIES OVER THE AREA. ANY RISK FOR DIURNALLY-FORCED SHOWERS AND
THUNDERSTORMS SHOULD MAINLY BE CONFINED TO AREAS WEST OF I-81.
CHANCES WILL MAINLY BE CAPPED AT AROUND 20 TO 30 PERCENT AS THE MAIN
AXIS OF FORCING DOES NOT ARRIVE UNTIL THE WEEKEND.
AS THE WEEKEND ARRIVES, CONVECTIVE CHANCES INCREASE AS A SLEW OF
UPSTREAM DISTURBANCES TRACK IN FROM THE OHIO VALLEY AND GREAT LAKES
REGION. WHILE IT IS DIFFICULT TO DETERMINE THE DEGREE OF SEVERE
THREAT, THERE SHOULD BE PLENTY OF HEAT AND HUMIDITY TO WORK WITH TO
BRING SCATTERED TO NUMEROUS THUNDERSTORMS OVER THE REGION. SUCH
THUNDERSTORM CHANCES GENERALLY RANGE FROM 40 TO 60 PERCENT, SLIGHTLY
HIGHER ON SUNDAY. GIVEN THE UPTICK IN CLOUD COVER FROM APPROACHING
THUNDERSTORMS, TEMPERATURES DROP OFF A BIT, BUT STILL REMAIN ABOVE
AVERAGE. THE COLD FRONT RESPONSIBLE FOR THIS CONVECTION SHOULD TRACK
THROUGH LATE IN THE WEEKEND BEFORE STALLING NEARBY INTO MONDAY.
TYPICALLY MID-SUMMER BOUNDARIES STRUGGLE TO COMPLETELY CLEAR THE
AREA. THUS, EXPECT THIS SYSTEM TO LINGER NEAR THE AREA INTO EARLY
NEXT WEEK.
AVIATION /18Z TUESDAY THROUGH SATURDAY/
MAINLY VFR CONDITIONS ARE EXPECTED THROUGH THE MIDDLE OF THE
WEEK AS CANADIAN HIGH PRESSURE TO OUR NORTH SLIDES OFFSHORE. A
PERIOD OF LOWER CIGS CAN'T BE RULED OUT IN LIGHT ONSHORE FLOW
EARLY WEDNESDAY MORNING, AND AGAIN LATE WEDNESDAY NIGHT INTO
EARLY THURSDAY MORNING. PATCHY FOG IS ALSO POSSIBLE MAINLY NEAR
CHO/MRB LATE EACH NIGHT/EARLY EACH MORNING. LIGHT E WINDS TODAY
WILL BECOME SE WEDNESDAY, THEN S THURSDAY.
MAINLY VFR CONDITIONS ARE EXPECTED ON FRIDAY WITH CONVECTIVE CHANCES
LIKELY REMAINING OFF TO THE WEST OF THE TERMINALS. SATURDAY OFFERS A
BETTER CHANCE FOR SHOWERS AND THUNDERSTORMS. THUS, SOME AFTERNOON
AND EVENING RESTRICTIONS ARE POSSIBLE. SOME SEVERE THREAT ALSO LOOMS
IN THIS HOT AND HUMID PATTERN. INITIAL WINDS WILL BE OUT OF THE
SOUTHWEST BEFORE SHIFTING TO WESTERLY BY SATURDAY.
MARINE
CANADIAN HIGH PRESSURE OVER THE REGION WILL SLOWLY SLIDE
OFFSHORE THROUGH MID WEEK. THIS CAUSES WINDS TO BECOME SOUTHEAST
BY LATE TONIGHT. FAVORABLE MARINE CONDITIONS ARE LIKELY TO
PERSIST FOR MOST OF THIS TIME, THOUGH SOUTHERLY CHANNELING
THURSDAY EVENING INTO THURSDAY NIGHT COULD BRING WINDS TO NEAR
SCA LEVELS OVER THE CHESAPEAKE BAY. THERE ARE HINTS OF BRIEF
BAY/RIVER BREEZE ENHANCEMENTS DURING THE LATE AFTERNOON TO EARLY
EVENING HOURS EACH OF THE NEXT FEW DAYS, BUT THESE SHOULD BE
ABLE TO BE HANDLED WITH MWSS, IF NECESSARY.
WIND FIELDS SHOULD STAY BELOW ADVISORY LEVELS THROUGH SATURDAY.
INITIAL WINDS WILL BE OUT OF THE SOUTH BEFORE SHIFTING TO SOUTHWEST
TO WESTERLY ON SATURDAY. CONVECTIVE CHANCES INCREASE ON SATURDAY
WHICH MAY SUPPORT SOME SPECIAL MARINE WARNINGS FOR ANY MORE ROBUST
STORMS.
TIDES/COASTAL FLOODING
BY THE MIDDLE OF THE WEEK, WATER LEVELS ARE EXPECTED TO RISE ON
SOUTHEAST WINDS. SNAPBACK TIDE COULD PUSH WATER LEVELS INTO
MINOR FLOOD STAGE AT SOME SENSITIVE LOCATIONS (MAINLY ANNAPOLIS)
BY THE MIDDLE OF THE WEEK.
LWX WATCHES/WARNINGS/ADVISORIES
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.
SYNOPSIS...DHOF/KRR
NEAR TERM...DHOF/KRR
SHORT TERM...DHOF/KRR
LONG TERM...BRO
AVIATION...BRO/DHOF/KRR
MARINE...BRO/DHOF/KRR
TIDES/COASTAL FLOODING...LWX
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