109  
FXUS61 KCLE 062337  
AFDCLE  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE CLEVELAND OH  
737 PM EDT SAT SEP 6 2025  
   
SYNOPSIS
 
 
A DEEP TROUGH OF LOW PRESSURE WILL PERSIST ACROSS THE GREAT  
LAKES THROUGH SUNDAY BEFORE A LARGE DOME OF CANADIAN HIGH  
PRESSURE BUILDS IN SUNDAY NIGHT AND MONDAY. THIS HIGH WILL  
REMAIN IN CONTROL THROUGH MIDWEEK WHILE GRADUALLY SHIFTING  
OFFSHORE OF THE NEW ENGLAND COAST.  
 

 
   
NEAR TERM /THROUGH SUNDAY NIGHT/
 
 
MID AFTERNOON VISIBLE SATELLITE AND WATER VAPOR LOOPS NICELY  
HIGHLIGHT AN UNSEASONABLY DEEP MID/UPPER LONGWAVE TROUGH ACROSS  
CENTRAL AND EASTERN NORTH AMERICA DOWNSTREAM OF A STRONG  
MID/UPPER RIDGE WEST OF THE ROCKIES EXTENDING WELL NORTH THROUGH  
BRITISH COLUMBIA. THIS HIGHLY AMPLIFIED PATTERN WILL MAINTAIN  
WELL BELOW AVERAGE TEMPERATURES AND BREEZY CONDITIONS THE  
REMAINDER OF THE WEEKEND, AS WELL AS PERIODS OF LAKE-EFFECT RAIN  
SHOWERS GIVEN THE STRONG COLD AIR ADVECTION AND WELL-ALIGNED  
MOIST, CYCLONIC FLOW ACROSS THE ROUGHLY 70 F LAKE WATERS.  
 
IN TERMS OF THE LAKE-EFFECT, DRIER AIR AND SUBSIDENCE BEHIND AN  
UPPER JET MAX AND ASSOCIATED SURFACE TROUGH THAT MOVED THROUGH  
THIS MORNING HAS SLOWED THE DEVELOPMENT OF LAKE-EFFECT RAIN  
BANDS. REGIONAL RADAR AS OF MID AFTERNOON SHOWS LAKE-EFFECT  
SHOWERS AND INSTABILITY SHOWERS FILLING IN UPSTREAM ACROSS  
NORTHERN AND CENTRAL LOWER MICHIGAN, AND THESE ARE TIED TO THE  
COLDER POOL OF AIR BENEATH THE MAIN MID/UPPER TROUGH AXIS THAT  
WILL SWING THROUGH THE SOUTHERN GREAT LAKES TONIGHT. AS THIS  
TROUGH AXIS APPROACHES THIS EVENING, DEEPENING SYNOPTIC MOISTURE  
AND BETTER ALIGNED WSW BOUNDARY LAYER FLOW COMBINED WITH  
DEEPENING INSTABILITY AND RESULTANT LAKE INDUCED EQUILIBRIUM  
LEVELS WILL ALLOW A SINGLE, DOMINANT BAND TO DEVELOP OVER THE  
LAKE AND AFFECT WESTERN NY AND PERHAPS NORTHEAST PARTS OF ERIE  
COUNTY, PA. AS THE MID/UPPER TROUGH AXIS SWINGS EASTWARD THROUGH  
THE NIGHT, AN ASSOCIATED SURFACE TROUGH WILL SLOWLY PRESS  
ACROSS THE LAKE, AND THIS COMBINED WITH BOUNDARY LAYER FLOW  
VEERING W AND EVENTUALLY WNW WILL SLOWLY PUSH THE BAND INLAND  
ACROSS THE PRIMARY SNOWBELT OF EASTERN CUYAHOGA, LAKE, GEAUGA,  
ASHTABULA, AND ERIE AND CRAWFORD COUNTIES IN PA. THE INCREASING  
SOUTH SHORE CONVERGENCE AS THE SURFACE TROUGH MOVES THROUGH  
COMBINED WITH EQUILIBRIUM LEVELS RISING TO AROUND 15,000 FEET  
AND LAKE INDUCED CAPE REACHING ABOUT 750 J/KG LATE TONIGHT WILL  
SUPPORT PERIODS OF HEAVY RAIN WITHIN THE MAIN BAND, AS WELL AS  
SOME THUNDER AND LIGHTNING. UTILIZED A BLEND OF RGEM AND WRF-ARW  
FOR POPS AND QPF TONIGHT AND SUNDAY MORNING TO TRY AND BEST  
CAPTURE THE MOVEMENT AND PLACEMENT OF THE MAIN BAND. AFTER 12Z  
SUNDAY, AN ESTABLISHING 290-300 DEGREE BOUNDARY LAYER FLOW MAY  
PUSH THE BAND AS FAR SW AS NORTHERN LORAIN, SOUTHERN CUYAHOGA,  
NORTHERN MEDINA, SUMMIT, AND PORTAGE COUNTIES BEFORE WEAKENING  
AND GIVING WAY TO MORE SCATTERED LAKE-EFFECT SHOWERS BY LATE  
MORNING THROUGH THE AFTERNOON AS DRIER AIR AND INCREASING  
SUBSIDENCE GRADUALLY BUILD IN. MOST AREAS OF NE OHIO AND NW PA  
SHOULD SEE UNDER 0.25 INCHES OF QPF, BUT LOCALIZED AMOUNTS OF  
0.50 TO 1 INCH CANNOT BE RULED OUT WHERE THE BAND PERSISTS WHICH  
APPEARS TO BE MOST LIKELY FROM THE EAST SUBURBS OF CLEVELAND  
INTO GEAUGA COUNTY IN THE ROUGHLY 09-13Z TIMEFRAME SUNDAY  
MORNING. A LARGE SURFACE HIGH OVER THE UPPER MIDWEST WILL BUILD  
IN SUNDAY NIGHT, GRADUALLY SHUTTING DOWN THE REMAINING LAKE-  
EFFECT SHOWERS, BUT KEPT THE TREND OF HANGING ONTO AT LEAST  
SLIGHT CHANCE POPS IN FAR NE OHIO AND NW PA LONGER.  
 
HIGHS SUNDAY WILL BE LIMITED TO THE MID/UPPER 60S, WITH LOW/MID  
60S IN NE OHIO AND NW PA. LOWS TONIGHT WILL FALL INTO THE  
LOW/MID 40S, EXCEPT LOW 50S NEAR THE LAKESHORE. AS THE HIGH  
BUILDS IN SUNDAY NIGHT, LOW 40S WILL BE WIDESPREAD INLAND FROM  
THE LAKE, WITH A FEW UPPER 30S POSSIBLE ALONG THE U.S. 30  
CORRIDOR AND IN INTERIOR NE OHIO AND NW PA, BUT EXPECT  
TEMPERATURES TO REMAIN A FEW DEGREES ABOVE FROST THRESHOLDS AT  
THIS TIME.  
 

 
   
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/
 
 
THE CHILLY PATTERN WILL GRADUALLY RELAX EARLY IN THE WEEK AS THE  
BIG CANADIAN HIGH CENTERED OVER THE SOUTHERN GREAT LAKES MONDAY SHIFTS  
OFF THE NEW ENGLAND COAST BY TUESDAY NIGHT, WITH MID-LEVEL  
HEIGHTS ALSO REBOUNDING IN RESPONSE TO THE WEST COAST RIDGE  
BREAKING DOWN AND AN UPPER LOW PROGRESSING ONSHORE OF OREGON AND  
CALIFORNIA. THIS WILL SET UP SPECTACULAR EARLY FALL WEATHER,  
WITH PLENTY OF SUNSHINE AND HIGHS IN THE UPPER 60S/LOW 70S  
MONDAY WARMING INTO THE MID/UPPER 70S TUESDAY. LOWS WILL ALSO BE  
MODERATING, WITH GENERALLY LOW/MID 40S MONDAY NIGHT (50S NEAR  
THE LAKE) INCREASING TO UPPER 40S/MID 50S TUESDAY NIGHT.  
 

 
   
LONG TERM /WEDNESDAY THROUGH SATURDAY/
 
 
QUIET WEATHER WILL CONTINUE IN THE EXTENDED, BUT TEMPERATURES  
WILL COOL A FEW DEGREES AFTER THE MID WEEK WARMTH BEHIND A COLD  
FRONT AND ASSOCIATED MID/UPPER TROUGH THAT PROGRESSES THROUGH  
THE GREAT LAKES WEDNESDAY NIGHT AND THURSDAY. THIS TROUGH WILL  
NOT BE NEARLY AS STRONG, BUT GUIDANCE SUGGESTS TROUGHING AND  
ASSOCIATED NW FLOW TO CONTINUE ACROSS THE GREAT LAKES AND NE  
CONUS THROUGH NEXT WEEKEND ALONG WITH ANOTHER CANADIAN HIGH  
SETTLING INTO THE REGION, SO SLIGHTLY COOLER AND MAINLY DRY  
CONDITIONS WILL PERSIST. USED NBM POPS AT THIS POINT, WHICH ARE  
COMPLETELY DRY WEDNESDAY THROUGH SATURDAY, BUT WILL NEED TO  
EVALUATE FOR POSSIBLE SHOWERS WITH THE FRONT WEDNESDAY  
NIGHT/THURSDAY DEPENDING ON THE DEGREE OF FORCING AND MOISTURE.  
 
HIGHS IN THE UPPER 70S/LOW 80S WEDNESDAY WILL COOL INTO THE MID  
70S TO NEAR 80 THURSDAY AND GENERALLY LOW/MID 70S FRIDAY AND  
SATURDAY.  
 

 
   
AVIATION /00Z SUNDAY THROUGH THURSDAY/
 
 
VFR ACROSS THE TAF SITES THIS EVENING WITH PRIMARILY VFR TO  
PERSIST THROUGH THE TAF PERIOD. MAIN CONCERN WILL BE THE  
POTENTIAL FOR LAKE EFFECT RAIN SHOWERS TO IMPACT ERI/CLE  
OVERNIGHT INTO SUNDAY MORNING. CONFIDENCE REMAINS LOW SINCE ANY  
BAND THAT DEVELOPS WILL BE NARROW, SO OPTED TO MAINTAIN PROB30  
AT ERI AND ALSO INTRODUCED A PROB30 AT CLE FOR MVFR VSBYS.  
OTHERWISE, SCT DECKS AROUND 5KFT MAY DEVELOP AREAWIDE SUNDAY  
AFTERNOON.  
 
WINDS WILL GENERALLY FAVOR A SOUTHWEST DIRECTION OVERNIGHT, 5  
KNOTS OR LESS. WINDS WILL SHIFT TOWARDS THE NORTHWEST LATE  
SUNDAY MORNING AND AFTERNOON, 8 TO 10 KNOTS.  
 
OUTLOOK...NON-VFR POSSIBLE IN LAKE EFFECT RAIN AND CLOUDS ACROSS  
NORTHEAST OHIO AND NORTHWEST PENNSYLVANIA SUNDAY NIGHT INTO  
MONDAY. OTHERWISE, MAINLY VFR EXPECTED THROUGH THURSDAY.  
 

 
   
MARINE
 
 
ELEVATED WESTERLY TO NORTHWESTERLY WINDS 15-25 KNOTS WILL  
REMAIN OVER LAKE ERIE THROUGH SUNDAY NIGHT. ONSHORE FLOW WILL  
ALLOW FOR WAVE HEIGHTS TO BUILD TO 3-6 FEET THROUGH THE WEEKEND.  
A SMALL CRAFT ADVISORY AND BEACH HAZARDS STATEMENT REMAINS IN  
EFFECT ACROSS THE CENTRAL AND EASTERN BASINS AND CORRESPONDING  
LAKESHORE COUNTIES THROUGH SUNDAY EVENING. WATERSPOUTS REMAIN  
POSSIBLE IN ANY LAKE EFFECT RAIN SHOWERS TONIGHT INTO SUNDAY.  
 
AN EXPANSIVE AREA OF HIGH PRESSURE WILL BUILD ACROSS THE GREAT  
LAKES REGION SUNDAY NIGHT AND PERSIST ACROSS THE NORTHEAST INTO  
EARLY NEXT WEEK. WINDS BECOME LIGHT AND VARIABLE ON MONDAY  
BEFORE FAVORING AN OFFSHORE COMPONENT TUESDAY AND WEDNESDAY AS  
THE HIGH BUILDS OVERHEAD.  
 

 
   
CLE WATCHES/WARNINGS/ADVISORIES
 
 
OH...BEACH HAZARDS STATEMENT THROUGH SUNDAY EVENING FOR OHZ010>012-  
089.  
PA...BEACH HAZARDS STATEMENT THROUGH SUNDAY EVENING FOR PAZ001.  
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT SUNDAY FOR LEZ145>149.  
 

 
 

 
 
SYNOPSIS...GARUCKAS  
NEAR TERM...GARUCKAS  
SHORT TERM...GARUCKAS  
LONG TERM...GARUCKAS  
AVIATION...KAHN  
MARINE...13  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab OH Page
The Nexlab PA Page Main Text Page