722  
FXUS61 KPBZ 241742  
AFDPBZ  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PITTSBURGH PA  
142 PM EDT FRI OCT 24 2025  
   
SYNOPSIS
 
 
LAKE-EFFECT SHOWERS TAPER TONIGHT INTO SATURDAY. FROST AND  
FREEZE CONCERNS CONTINUE EACH MORNING THROUGH THE WEEKEND.  
LARGE FORECAST UNCERTAINTY DEVELOPS MID-TO-LATE NEXT WEEK.  
 

 
   
NEAR TERM /THROUGH TONIGHT/
 
 
KEY MESSAGES:  
 
- LAKE-EFFECT SHOWERS TAPER OFF NORTH OF I-80 AFTER SUNSET  
- FROST AND FREEZE CONCERNS RETURN TONIGHT  
---------------------------------------------------------------  
 
THE UPPER TROUGH OVER EASTERN CANADA BEGINS TO SHIFT EAST  
TONIGHT, RESULTING IN A SHIFT TO NORTHWEST FLOW WHICH WILL HELP  
FILTER DRIER AIR INTO THE AREA. AS A RESULT, LAKE-EFFECT SHOWERS  
WILL GRADUALLY TAPER OVERNIGHT.  
 
THE MAIN CONCERN TONIGHT IS THE POTENTIAL FOR FROST/FREEZE  
CONDITIONS ACROSS THE AREA. LOCATIONS WHERE CLOUDS ARE ABLE TO  
SCATTER/CLEAR WILL DETERMINE WHERE TEMPERATURES WILL BE  
COLDEST. NORTH OF PITTSBURGH, PERSISTENT LAKE-EFFECT CLOUDS IN  
WEAK NORTHWEST FLOW (EVEN AFTER SHOWERS DISSIPATE) SHOULD HELP  
KEEP TEMPERATURES ABOVE FREEZING. NEAR AND SOUTH/WEST OF  
PITTSBURGH, IT'LL BE A RACE BETWEEN HOW FAST CLOUDS DRIVEN BY  
DAYTIME HEATING/MIXING CAN DISSIPATE AND HOW FAST UPPER-LEVEL  
CLOUDS OVERSPREAD THE AREA FROM SOUTH TO NORTH AHEAD OF LOW  
PRESSURE MOVING INTO THE CENTRAL MISSISSIPPI VALLEY. LATEST  
ENSEMBLES (BOTH HREF AND NBM) SUGGEST THE MOST LIKELY AREA TO  
SEE A BREAK IN CLOUD COVER BETWEEN THESE FEATURES WILL BE ALONG  
A BELT OF COUNTIES EXTENDING FROM ROUGHLY COSHOCTON/TUSCARAWAS  
IN EASTERN OH TO FAYETTE/WESTMORELAND IN SOUTHWEST PA.  
 
A FREEZE WARNING IS IN EFFECT FOR THAT STRETCH OF COUNTIES FROM  
MIDNIGHT TONIGHT UNTIL 9 AM SATURDAY MORNING. THE FREEZE  
WARNING ALSO EXTENDS SOUTH INTO NORTHERN WEST VIRGINIA, BUT  
THERE IS SLIGHTLY LESS CONFIDENCE THAT FAR SOUTH AS HIGH CLOUDS  
COULD MOVE IN AND MITIGATE RADIATIVE COOLING BEFORE TEMPERATURES  
DROP BELOW FREEZING. LATER SHIFTS WILL NEED TO MONITOR  
SATELLITE AND TEMPERATURE TRENDS, AND MAY END UP NEEDING TO TRIM  
THE WARNING IF THAT OCCURS.  
 

 
   
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/
 
 
KEY MESSAGES:  
 
- ENDING PRECIPITATION IN NORTHWEST PA; DRY OTHERWISE  
- TEMPERATURE RISING TOWARD SEASONAL AVERAGE  
----------------------------------------------------------------  
 
A LAST UPPER LEVEL SHORTWAVE HEADING TOWARD NEW ENGLAND MAY BE  
ENOUGH TO KEEP LOW PROBABILITY LAKE EFFECT SHOWERS DURING THE  
DAYTIME HOURS SATURDAY NORTH OF I-80. OTHERWISE, HIGH PRESSURE  
AND SUBSIDENCE OVER THE OHIO RIVER VALLEY IS EXPECTED TO SUPPORT  
DRY WEATHER. THOUGH HEIGHT RISES SHOULD OFFER STRONGER  
TEMPERATURE MODERATION, A LIFTING SOUTHERN STREAM TROUGH  
APPROACHING THE TENNESSEE RIVER VALLEY MAY PROVIDE ENOUGH HIGH-  
LEVEL MOISTURE TO LIMIT INSOLATION (ALONG WITH LAKE-ENHANCED  
DIURNAL CU) AND ACT TO TEMPER SOME OF THE EXPECTED TEMPERATURE  
RISES.  
 
THAT TROUGH WILL SETTLE SOUTH OF THE REGION SUNDAY WHILE RIDGING  
DEVELOPS OVER THE WESTERN GREAT LAKES PLUS ANOTHER DEEP TROUGH  
SITS OVER NORTHERN NEW ENGLAND. WEDGED BETWEEN THESE FEATURES  
BUT REMAINING UNDER THE INFLUENCE OF SURFACE HIGH PRESSURE MEANS  
DRY WEATHER CONTINUES FOR MOST OF THE AREA WITH A MIX OF SUN AND  
CLOUDS ALLOWING TEMPERATURE TO BE WITHIN A FEW DEGREES OF  
NORMAL. LATE DAY APPROACH OF THE SOUTHERN STREAM TROUGH CREATES  
LOW PROBABILITY RAIN CHANCES LATE SUNDAY NIGHT ALONG THE WV  
HIGHER TERRAIN; IF THIS OCCURS, LOW TEMPERATURE MAY BE MORE MILD  
THAN FORECAST AND THUS NOT RESULT IN ANY SNOW FORMATION.  
 

 
   
LONG TERM /MONDAY THROUGH FRIDAY/
 
 
KEY MESSAGES:  
 
- HIGHLY VARIABLE LONG RANGE FORECAST THAT FAVORS A TREND TOWARD  
A COOLER, MORE WET PATTERN  
-------------------------------------------------------------------  
 
THE UPPER OHIO RIVER VALLEY IS LIKELY TO REMAIN WEDGED BETWEEN  
THE THREE UPPER LEVEL FEATURES (GREAT LAKES RIDGE, NEW ENGLAND  
TROUGH, TENNESSEE VALLEY TROUGH) MONDAY WHILE AWAITING NOTABLE  
UPPER LEVEL ENERGY TO ARRIVE FROM THE PACIFIC NORTHWEST. THERE  
IS REASONABLY HIGH CONFIDENCE FOR THIS TO MAINTAIN SEASONABLE  
TEMPERATURE AND ANY PRECIPITATION CHANCES REMAINING SOUTH OF  
I-70 DEPENDING ON THE DEGREE OF NORTHWARD MOVEMENT OF THE  
TENNESSEE TROUGH.  
 
CLUSTER ANALYSIS OF ENSEMBLE WEATHER MODELING FOR TUESDAY INTO  
LATE NEXT WEEK SHOWS LARGE VARIABILITY IN THE BROADER 500MB  
PATTERN EVOLUTION; CURRENT MEANS AND FORECASTED VALUES FOLLOW A  
TREND OF A POTENT UPPER TROUGH PHASING WITH THE TN TROUGH WHILE  
DISPLACING THE GREAT LAKES RIDGE NORTHWARD AND RESULT IN A  
BROADER EASTERN CONUS TROUGH AXIS. THIS PORTENDS A PROLONGED  
PERIOD OF BELOW AVERAGE TEMPERATURE WITH PERIODIC PRECIPITATION  
CHANCES WITH POTENTIAL FOR ENOUGH COLD ADVECTION TO CREATE WV  
HIGH TERRAIN SNOW BY THE END OF THE WEEK. HOWEVER, THAT CLUSTER  
ANALYSIS SHOWS TROUGH POSITIONING TO STRETCH FROM AS FAR WEST AS  
TX AND AS FAR EAST AS THE ATLANTIC COAST; TEMPERATURE PROFILES  
RANGE FROM ABOVE NORMAL READINGS TO WELL BELOW NORMAL READINGS  
AND PRECIPITATION CHANCES (LET ALONE AMOUNTS) WILDLY OSCILLATING  
FROM THERE. ADDITIONAL MODEL RUNS WILL BE NEEDED TO BETTER SORT  
OUT THE HIGHLY VARIABLE PATTERN, BUT IT DOES APPEAR THE  
POTENTIAL FOR IMPACTFUL WEATHER (LIKELY TIED TO SNOWFALL  
ACCUMULATION) IS VERY LOW.  
 

 
   
AVIATION /18Z FRIDAY THROUGH WEDNESDAY/
 
 
VFR STRATOCU ARE ONGOING ACROSS MUCH OF THE AREA THIS AFTERNOON,  
SAVE FOR LINGERING PATCHES OF MVFR CEILINGS IN LAKE-EFFECT  
CLOUDS FROM PIT/AGC UP TO FKL/DUJ. WIDESPREAD VFR IS EXPECTED BY  
LATER THIS AFTERNOON AND SHOULD PREVAIL THROUGH THE REST OF THE  
FORECAST PERIOD, THOUGH THERE REMAINS A LOW PROBABILITY FOR  
CEILINGS TO DROP BACK TO MVFR AT FKL/DUJ OVERNIGHT. RAIN SHOWERS  
TAPER OFF AFTER DARK AS DRY AIR BEGINS TO FILTER INTO THE AREA.  
WINDS WILL BE LIGHT AND GRADUALLY SHIFT TO NORTHERLY AND THEN  
EAST-NORTHEASTERLY TONIGHT INTO SATURDAY.  
   
OUTLOOK
 
 
AREAWIDE VFR RETURNS OVER THE WEEKEND AS THE TROUGH AXIS SHIFTS  
EAST AND WEAK RIDGING BUILDS OVERHEAD. ANOTHER SYSTEM COULD  
RETURN RAIN AND RESTRICTION CHANCES FROM THE SOUTH EARLY NEXT  
WEEK.  
 

 
   
PBZ WATCHES/WARNINGS/ADVISORIES
 
 
PA...FREEZE WARNING FROM MIDNIGHT TONIGHT TO 9 AM EDT SATURDAY FOR  
PAZ020-021-029-031-073>076.  
OH...FREEZE WARNING FROM MIDNIGHT TONIGHT TO 9 AM EDT SATURDAY FOR  
OHZ039>041-048>050-057>059-068-069.  
WV...FREEZE WARNING FROM MIDNIGHT TONIGHT TO 9 AM EDT SATURDAY FOR  
WVZ001>004-012-021-509>514.  
 

 
 

 
 
SYNOPSIS...CERMAK  
NEAR TERM...CERMAK  
SHORT TERM...FRAZIER  
LONG TERM...FRAZIER  
AVIATION...CERMAK  
 
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