411  
FXUS61 KPBZ 161340  
AFDPBZ  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PITTSBURGH PA  
940 AM EDT TUE SEP 16 2025  
   
SYNOPSIS  
 
DRY WEATHER AND ABOVE-NORMAL TEMPERATURES DOMINATE THE FORECAST  
THIS WEEK UNDER THE INFLUENCE OF HIGH PRESSURE. REASONABLE RAIN  
CHANCES LIKELY WILL NOT RETURN UNTIL SUNDAY OR MONDAY AT THE  
EARLIEST.  
 
 
   
NEAR TERM /THROUGH TONIGHT/  
 
KEY MESSAGES:  
 
- CONTINUED DRY WEATHER  
- SLIGHT TEMPERATURE MODERATION, BUT STILL ABOVE NORMAL  
---------------------------------------------------------------  
 
THE LOCAL AREA REMAINS SANDWICHED BETWEEN HIGH PRESSURE TO OUR  
NORTH AND LOW PRESSURE TO OUR SOUTHEAST CENTERED OVER THE  
CAROLINAS. THIS PATTERN MAINTAINS LIGHT NORTHEAST WINDS AND DRY  
CONDITIONS, WITH PERIOD OF HIGH CLOUDS MOVING THROUGH AS THEY  
WRAP AROUND THE NORTHERN PERIPHERY OF THE LOW. ABOVE-NORMAL  
TEMPERATURES CONTINUE, THOUGH WITH SOME SLIGHT MODERATION AS  
HIGHS REACH THE LOW 80S.  
 
 
   
SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/  
 
KEY MESSAGES:  
 
- DRY FOR MOST OF THE REGION, SAVE FOR LOW SHOWER CHANCES IN THE  
HIGHER ELEVATIONS  
- ABOVE-NORMAL TEMPERATURES CONTINUE  
--------------------------------------------------------------  
 
THE LOW CURRENTLY CENTERED OVER THE CAROLINAS IS EXPECTED TO  
SLOWLY CHURN NORTHWARD THROUGH MIDWEEK, REACHING THE DELMARVA  
REGION BY WEDNESDAY NIGHT. THE MAIN IMPACT FOR MUCH OF THE  
REGION WEST OF THE PA/WV RIDGES WILL CONTINUE TO BE WAVES OF  
HIGH CLOUD SPINNING IN FROM THE EAST, AS RIDGING REMAINS IN  
CONTROL OVER THE UPPER OHIO VALLEY.  
 
ALONG EAST-FACING SLOPES, ENOUGH ATLANTIC MOISTURE AND UPSLOPE  
FLOW MAY BE REALIZED TO ALLOW THE DEVELOPMENT OF SOME LIGHT RAIN  
SHOWERS, WITH TONIGHT AND WEDNESDAY STILL THE MOST FAVORED  
PERIOD. UNFORTUNATELY, ANY PRECIPITATION WOULD BE VERY LIGHT  
AND DO LITTLE TO THE DEVELOPING DROUGHT OVER THE REGION.  
DOWNSLOPING TO THE WEST OF THE RIDGES WILL HELP TO SUPPRESS  
PRECIPITATION AWAY FROM THE HIGHER ELEVATIONS, WITH LOWLAND  
AREAS REMAINING DRY THROUGHOUT THE SHORT TERM.  
 
DAYTIME HIGHS ON WEDNESDAY WILL BE SIMILAR TO TODAY (ABOVE-  
AVERAGE), WHILE NIGHTTIME LOWS REMAIN CLOSER TO AVERAGE THANKS  
TO THE DRY AIR AND EFFICIENT RADIATIVE COOLING.  
 
 
   
LONG TERM /THURSDAY THROUGH MONDAY/  
 
KEY MESSAGES:  
 
- ABOVE-AVERAGE TEMPERATURES CONTINUE  
- PROLONGED DRY WEATHER CONTINUES THROUGH SATURDAY  
- MINIMAL RAIN CHANCES RETURN FOR SUNDAY AND MONDAY  
------------------------------------------------------------------  
 
BY THURSDAY MORNING, THE COASTAL LOW OPENS UP INTO A SHORTWAVE  
TROUGH THAT SLOWLY EDGES OUT TO SEA WITH TIME. MEANWHILE, THE MID-  
LEVEL RIDGE ALSO SHIFTS EASTWARD ACCORDINGLY, WITH THE AXIS OVER THE  
UPPER OHIO VALLEY BY SATURDAY MORNING. A WEAK FRONTAL BOUNDARY  
MAY DROP SOUTH INTO OUR REGION ON THE FRONT SIDE OF THE  
APPROACHING RIDGE, BUT ANY SUCH PASSAGE IS NOT EXPECTED TO  
THREATEN THE OVERALL DRY REGIME THROUGH SATURDAY.  
 
WITH 500MB HEIGHTS RISING, HIGH TEMPERATURES WILL ONCE AGAIN  
RISE TO AROUND 10 DEGREES ABOVE NORMAL TO CLOSE OUT THE WORK  
WEEK. IN CONTRAST, OVERNIGHT LOWS SHOULD REMAIN FAIRLY CLOSE TO  
SEASONABLE WITH THE DRY AIR AND DECENT RADIATIONAL COOLING  
OPPORTUNITIES.  
 
THERE CONTINUES TO BE DISAGREEMENT AMONG THE VARIOUS MODEL  
CLUSTERS REGARDING THE PATTERN LATE THIS WEEKEND INTO EARLY NEXT  
WEEK. THE BIG QUESTION MARK IS HOW AN EAST COAST RIDGE HANDLES  
THE NEXT UPSTREAM TROUGH WHICH IS EXPECTED TO MOVE INTO THE  
UPPER MIDWEST ON SUNDAY. IF THE RIDGE HOLDS FIRM, WE'D CONTINUE  
TO SEE ABOVE-NORMAL TEMPERATURES AND DRY CONDITIONS LOCALLY AS  
THE UPSTREAM TROUGH (AND ANY ASSOCIATED MOISTURE/PRECIPITATION)  
WOULD BE SHUNTED NORTHWARD INTO SOUTHERN ONTARIO. HOWEVER, SOME  
SOLUTIONS SUGGEST THE RIDGE GIVES WAY AND PUSHES TO THE EAST OR  
SOUTHEAST, ALLOWING SOME SHORTWAVE ACTIVITY TO MAKE IT ACROSS  
THE OHIO VALLEY. IF THIS LATTER SCENARIO VERIFIES, IT WOULD  
BRING SOME LIGHT PRECIPITATION AND MORE SEASONAL TEMPERATURES TO  
THE AREA, WHICH WOULD BE WELCOME AT THIS POINT GIVEN THE  
DEVELOPING DROUGHT. FOR NOW, THE FORECAST INCLUDES A SLOW  
INCREASE IN LOW RAIN CHANCES AT THE TAIL END OF THE FORECAST,  
ALONG WITH A MODEST TREND TOWARDS COOLER TEMPERATURES.  
 
 
   
AVIATION /14Z TUESDAY THROUGH SATURDAY/  
 
HIGH CONFIDENCE VFR CONTINUES THROUGH THE TAF PERIOD AS HIGH  
PRESSURE REMAINS ACROSS THE REGION. WINDS WILL REMAIN LIGHT AND  
VARIABLE, THOUGH GENERALLY EASTERLY. SCATTERED AFTERNOON CU IS  
EXPECTED BETWEEN 7-10KFT. HIGH CLOUDS ARE EXPECTED TO BE MORE  
PREVALENT TODAY FILTERING IN FROM A COASTAL SYSTEM NEAR SE  
VIRGINIA.  
 
MORE NOTABLE HIGH CLOUD COVERAGE MAY KEEP THE LID ON FOG  
POTENTIAL OVERNIGHT, BUT BREAKS IN THIS MAY ALLOW FOR LOW END  
FOG POTENTIAL ESPECIALLY FOR FKL.  
   
OUTLOOK.  
 
SURFACE HIGH PRESSURE NEAR NEW ENGLAND WILL CONTINUE TO DOMINATE THE  
WEATHER PATTERN, PROMOTING VFR AND LIGHT EASTERLY WIND. CLEAR SKY  
NIGHTS MAY RESULT IN PATCHY RIVER FOG DURING THE PRE-DAWN HOURS.  
 
 
   
PBZ WATCHES/WARNINGS/ADVISORIES  
 
PA...NONE.  
OH...NONE.  
WV...NONE.  
 
 
 
 
 
SYNOPSIS...CERMAK/CL  
NEAR TERM...CERMAK/CL  
SHORT TERM...CERMAK/CL  
LONG TERM...CERMAK/CL  
AVIATION...AK/RACKLEY  
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