121  
FXUS61 KPBZ 292259  
AFDPBZ  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PITTSBURGH PA  
659 PM EDT TUE SEP 29 2026  
   
WHAT HAS CHANGED
 
 
UPCOMING WEEKEND PRECIPITATION CHANCES HAVE DECREASED, OTHERWISE  
NO MAJOR CHANGES WERE MADE TO THE LATEST FORECAST.  
 

 
   
KEY MESSAGES
 
 
1) MAINLY DRY THROUGH THURSDAY, BEFORE SHOWER CHANCES RETURN  
WITH A FRIDAY COLD FRONT  
 
2) COOLER WITH PERIODIC SHOWER CHANCES FOR THE UPCOMING WEEKEND  
 

 
   
DISCUSSION
 
 
KEY MESSAGE 1...  
A RIDGE OF HIGH PRESSURE IS EXPECTED TO MAINTAIN DRY WEATHER FOR  
MUCH OF THE AREA THROUGH THURSDAY. THE EXCEPTION IS WEDNESDAY  
NIGHT, WHERE A WEAK CROSSING SHORTWAVE AND WARM ADVECTION COULD  
RESULT IN A FEW SHOWERS NORTH OF PITTSBURGH. THE RIDGE SHOULD  
STRENGTHEN AGAIN ON THURSDAY AHEAD OF AN APPROACHING TROUGH,  
WITH DRY WEATHER RETURNING. THURSDAY WILL LIKELY BE THE WARMEST  
DAY OF THE WEEK, WITH HIGHS AROUND 80 OUTSIDE OF THE HIGHER  
TERRAIN.  
 
A SHORTWAVE TROUGH, AND AN ASSOCIATED SURFACE COLD FRONT, IS  
EXPECTED TO ADVANCE EASTWARD FROM THE MIDWEST ON THURSDAY,  
APPROACHING AND CROSSING THE UPPER OHIO VALLEY REGION ON FRIDAY.  
THE UPPER TROUGH IS PROGGED TO WEAKEN AS IT MOVES EASTWARD  
ACROSS OUR REGION ON FRIDAY. INCREASING FLOW ALOFT WILL RESULT  
IN INCREASING SHEAR DURING THE DAY, WITH THE AREA UNDER THE  
RIGHT ENTRANCE REGION TO AN UPPER LEVEL JET. INSTABILITY IS  
PROGGED TO REMAIN MINIMAL AT THIS TIME, WITH SB CAPE AROUND 250  
J/KG OR LESS, MAINLY SOUTH OF PIT. ML GUIDANCE INDICATES LITTLE  
POTENTIAL FOR SEVERE STORMS AS WELL. THE MOST FAVORABLE TIMING  
FOR FROPA IS EARLY AFTERNOON NORTH OF PIT, WITH MID TO LATE  
AFTERNOON FOR POINTS SOUTHWARD. AT THIS TIME, PROBABILITIES FOR  
AT LEAST A QUARTER OF AN INCH OF RAIN RANGE FROM 60 TO 80  
PERCENT, THOUGH ARE LESS THAN 50 PERCENT FOR A HALF AN INCH.  
 
KEY MESSAGE 2...  
BROAD UPPER TROUGHING IS PROGGED TO SET UP ACROSS THE NE CONUS  
THROUGH THE UPCOMING WEEKEND. SATURDAY SHOULD BE MAINLY DRY AND  
COOLER AS SURFACE HIGH PRESSURE BUILDS IN FROM THE NORTH, THOUGH  
A CROSSING SOUTHERN STREAM WAVE SHOULD RESULT IN SHOWER CHANCES  
MAINLY SOUTH OF I-70. SHOWER CHANCES THEN INCREASE ON SUNDAY AS  
A NORTHERN STREAM SHORTWAVE ROTATES THROUGH THE BROAD UPPER  
TROUGH. COOLER TEMPERATURES ARE EXPECTED, WITH HIGHS JUST BELOW  
SEASONABLE LEVELS.  
 

 
   
AVIATION /00Z WEDNESDAY THROUGH SUNDAY/
 
 
AS THE COAST LOW LIFTS TO THE NORTHEAST, CLOUD COVER OVER THE  
WESTERN PA AREA WILL BEGIN TO CLEAR OUT FROM WEST TO EAST. THIS  
WILL RESULT IN FOG DEVELOPMENT TONIGHT AND JUST ABOUT EVERY  
TERMINAL IS EXPECTED TO GO DOWN TO FIELD MINS. THIS WILL MAINLY  
BE DURING THE 08Z TO 13Z PERIOD. CONDITIONS WILL IMPROVE INTO  
THE DAY TOMORROW WITH LIGHT AND VARIABLE WINDS EXPECTED. THE  
ONLY CLOUD COVER WILL BE HIGH CLOUDS THROUGH THE DAY.  
 
OUTLOOK...  
VFR IS EXPECTED THROUGH THURSDAY, THOUGH A FEW SHOWERS ARE  
POSSIBLE N OF PIT WEDNESDAY NIGHT WITH A CROSSING DISTURBANCE.  
RESTRICTIONS IN SHOWERS ARE LIKELY WITH A FRIDAY COLD FRONT.  
RESTRICTIONS ARE POSSIBLE SOUTH OF I-70 SATURDAY, AND ACROSS THE  
REMAINDER OF THE ARE SUNDAY, WITH CROSSING DISTURBANCES.  
 

 
   
PBZ WATCHES/WARNINGS/ADVISORIES
 
 
PA...NONE.  
OH...NONE.  
WV...NONE.  
 

 
 

 
 
DISCUSSION...WM  
AVIATION...WM/SHALLENBERGER  
 
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