298
FXUS61 KPBZ 111123
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
723 AM EDT THU JUN 11 2026
WHAT HAS CHANGED
AVIATION DISCUSSION UPDATED FOR 12Z TAF ISSUANCE.
KEY MESSAGES
1) POTENTIAL FOR SEVERE WEATHER EXISTS TODAY AND FRIDAY, BUT
LARGE UNCERTAINTY EXISTS IN TIMING/COVERAGE/THREATS
2) LOW PROBABILITY FLASH FLOODING CONCERNS EXISTS THROUGH FRIDAY
DUE TO WARM, MOIST ENVIRONMENT
3) ABOVE-AVERAGE TEMPERATURE WITH POTENTIAL FOR RECORD HIGH
MINIMUMS POSSIBLE THROUGH FRIDAY, PENDING STORM OUTCOMES
DISCUSSION
KEY MESSAGE 1...
THE WARM, HUMID ENVIRONMENT WILL CONTINUE INTO FRIDAY, KEEPING
CHANCES FOR SHOWERS AND THUNDERSTORMS IN THE FORECAST.
ADDITIONAL THUNDERSTORMS ARE EXPECTED FRIDAY IN ADVANCE OF A
COLD FRONT AND CROSSING UPPER TROUGH. A BRIEF PERIOD OF DRY
WEATHER AND MORE SEASONABLE TEMPERATURE WILL FOLLOW.
CAMS CONTINUE TO SHOW SOME POSSIBILITY FOR ISOLATED/SCATTERED
SHOWERS AFTER SUNRISE THIS MORNING. CONFIDENCE IN THIS REMAINS
LOW. HOWEVER, CONFIDENCE IS INCREASING FOR SCATTERED
THUNDERSTORM ACTIVITY AGAIN THIS AFTERNOON AND EARLY EVENING.
COVERAGE AND EXACT TIMING OF STORMS REMAINS UNCERTAIN. HOWEVER,
SIMILAR TO TODAY, HIGH SBCAPE/DCAPE VALUES AND MEAGER SHEAR
SHOULD SUPPORT STORMS CAPABLE OF DAMAGING WIND GUSTS. MOST OF
THE AREA REMAINS IN A MARGINAL (1/5) RISK FOR SEVERE WEATHER.
FRIDAY FEATURES A MORE WELL DEFINED MID-LEVEL SHORTWAVE AND
SURFACE FRONTAL BOUNDARY THAT OFFERS A LIFTING MECHANISM, BUT
WIDE MODEL GUIDANCE SPREAD CONTINUES ON TIMING. THIS COULD
RESULT IN MORE BULLISH PRECIPITATION/SEVERE CHANCES (AFTERNOON
PASSAGE) OR MORE BEARISH PRECIPITATION/SEVERE CHANCES (OVERNIGHT
TO MID MORNING FRIDAY PASSAGE). LATEST CAM TRENDS NOW LEAN
TOWARDS EARLY AFTERNOON INITIATION FARTHER WEST OVER THE AREA.
THIS INCREASES OVERALL RAIN AND ASSOCIATED SEVERE RISKS.
KEY MESSAGE 2...
DESPITE FLUCTUATIONS IN MID-LEVEL MOISTURE CONTENT, AREA PWAT
VALUES WILL REMAIN IN THE 90TH AND HIGHER PERCENTILE RANGES
THROUGH FRIDAY WHILE THERMAL PROFILES REMAIN WARM. THESE FACTORS
ALONE CREATE NON-ZERO FLASH FLOOD RISKS AS THEY FAVOR WARM-RAIN
PROCESSES THAT RESULT IN HIGHER AND MORE EFFICIENT RAINFALL
RATES. ADD IN GENERALLY WEAKER MID-LEVEL FLOW (THOUGH STORM
MOTION QUICKENS FRIDAY), THE RISK FOR FLASH FLOODING EXISTS EACH
DAY.
HOWEVER, FAIRLY DRY SURFACES PLUS LOW CONFIDENCE IN STORM
COVERAGE/OCCURRENCE DAMPENS THE LIKELIHOOD OF FLASH FLOODING
ACTUALLY DEVELOPING FOR ANY OF THESE PERIODS. THE MOST LIKELY
OUTCOME IS MINIMAL FLOODING OCCURRENCES, WITH ISSUES ONLY
DEVELOPING IN POOR-DRAINAGE LOCATIONS THAT SEE PROLONGED 1-2"/HR
RATES OR AREAS THAT HAPPEN TO SEE MULTIPLE ROUNDS OF THESE
EFFICIENT RAINS IN A SHORT AMOUNT OF TIME.
KEY MESSAGE 3...
THE COMBINATION OF AREA DEW POINTS REMAINING IN THE UPPER 60S TO
LOWER 70S WHILE SEEING ENOUGH PERIODS OF SUNSHINE MEANS
INCREASED HEAT CONCERNS TODAY INTO FRIDAY MORNING, WITH IMPACTS
MORE ACUTELY IMPACTING HEAT-SENSITIVE POPULATIONS WITHIN URBAN
ENVIRONMENTS. THOUGH A BRIEF HOUR OF HEAT INDICES NEAR TO
MATCHING HEAT ADVISORY CRITERIA CAN'T BE RULED OUT, THIS IS
UNLIKELY TO BE PROLONGED ENOUGH FOR HEADLINE ISSUANCE. EVEN
STILL THE LACK OF SIGNIFICANT OVERNIGHT COOLING CAN ACT TO
EXASPERATE ANY HEAT-RELATED IMPACTS UNTIL A COOLER AIRMASS
ARRIVES FRIDAY NIGHT INTO SATURDAY MORNING.
THE BIGGEST CAVEAT TO THIS HEAT POTENTIAL IS THAT CONVECTIVE
ACTIVITY COULD ACT TO LIMIT DIURNAL HEATING (OR FURTHER LIMIT
OVERNIGHT COOLING) IF IT RESULTS IN RAIN OVER A GIVEN LOCATION
AND/OR MAINTAINS THICKER CLOUD COVER THAN ANTICIPATED.
AVIATION /12Z THURSDAY THROUGH MONDAY/
ISOLATED MORNING THUNDERSTORMS FEATURING IFR VIS EXIT EAST OF
FKL/DUJ BY 13/14Z, WITH THIS AREA JOINING THE REST OF THE
REGION IN VFR CONDITIONS (SAVE FOR POTENTIALLY BRIEF MVFR AMID
DIURNAL CU DEVELOPMENT) THAT SEE INCREASING SW WIND THROUGH THE
DAY.
THE WARM, HUMID ENVIRONMENT CONTINUES TO CREATE LOWER CONFIDENCE
TIMING/COVERAGE RELATED TO THUNDERSTORM DEVELOPMENT. BUT THE
MOST RECENT HI-RES MODEL TRENDS FAVOR ISOLATED TO SCATTERED
GENERALLY DISCRETE CELLS FORMING NEAR THE OH/PA/WV BORDERS
BETWEEN 16Z-19Z AND PROGRESSING EASTWARD. ANY THUNDERSTORM WILL
BE CAPABLE OF IFR VISIBILITIES IN HEAVY RAIN PLUS GUSTY AND
ERRATIC OUTFLOW WINDS THAT ARE MORE LIKELY TO BE IN THE 30 TO 45
MPH RANGE (BUT CONFIDENCE IS LOWER ON THIS FEATURE, THUS NO TAF
INCLUSION). OUTFLOW DEVELOPMENT COULD ALSO SPARK GREATER STORM
COVERAGE THAN ANTICIPATED, SO BE PREPARED FOR MORE FREQUENT TAF
AMENDMENTS ATTEMPTING TO BETTER CAPTURE RECENT TRENDS.
THE EXPECTATION IS FOR THE LOSS OF DIURNAL HEATING (AND NOTED
EXIT OF MID-LEVEL SHORTWAVE) TO CAUSE STORM DISSIPATION NEAR
00Z AND LEADING TO A QUIETER OVERNIGHT PERIOD. PENDING ON
STRENGTH OF LOW LEVEL JET AND MOISTURE FEED AHEAD OF AN INCOMING
SHORTWAVE/SURFACE BOUNDARY, THERE IS POTENTIAL FOR MVFR TO
LOCALIZED IFR CIGS TO DEVELOP NEAR DAWN FRIDAY MORNING AT OR
JUST AFTER THE END OF THE TAF PERIOD.
OUTLOOK...
CONFIDENCE REMAINS LOW IN THE COVERAGE AND LOCATION ON NEW STORM
DEVELOPMENT FRIDAY ALONG/AHEAD OF A PASSING UPPER SHORTWAVE AND
SURFACE COLD FRONT. ANY THUNDERSTORM THAT DEVELOPS LIKELY FAVORS
IFR VISIBILITIES, MVFR CIGS AND BRIEF GUSTY WIND; MOISTURE
CONVERGENCE AHEAD OF THE FRONT MAY ALSO PROVIDE A SHORT PERIOD
OF MVFR TO LOCALLY IFR CIGS.
DRY ADVECTION AND SUBSIDENCE IN THE POST-FRONTAL ENVIRONMENT
FAVORS VFR FRIDAY EVENING INTO SATURDAY. THE NEXT PRECIPITATION
CHANCE ARRIVES WITH SHORTWAVE MOVEMENT SUNDAY.
PBZ WATCHES/WARNINGS/ADVISORIES
PA...NONE.
OH...NONE.
WV...NONE.
DISCUSSION...RACKLEY/FRAZIER
AVIATION...FRAZIER
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