907  
FXUS61 KCLE 202038  
AFDCLE  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE CLEVELAND OH  
338 PM EST MON JAN 20 2025  
   
SYNOPSIS  
 
HIGH PRESSURE BUILDS THROUGH THE OHIO VALLEY TONIGHT. A RE-  
ENFORCING COLD FRONT CROSSES FROM WEST TO EAST ON TUESDAY. HIGH  
PRESSURE BUILDS BACK IN TUESDAY NIGHT INTO WEDNESDAY.  
 
 
   
NEAR TERM /THROUGH TUESDAY NIGHT/  
 
LAKE EFFECT SNOW HAS JUST ABOUT LIFTED OFFSHORE OF ERIE COUNTY,  
PA AND SHOULD BE ABLE TO LET THE WINTER WEATHER ADVISORY EXPIRE  
AT 4 PM. THIS SNOW BAND WILL SIT JUST OFFSHORE TONIGHT INTO  
EARLY TUESDAY AND COULD GRAZE THE ERIE COUNTY SHORELINE AT TIMES.  
OTHERWISE, WE SHOULD BE DONE WITH LES FOR THE TIME BEING.  
 
HIGH PRESSURE AND THE COLD, DRY ARCTIC AIRMASS WILL LEAD TO A  
COLD BUT QUIET AND CLEAR EVENING AND NIGHT. INTERESTINGLY  
ENOUGH, SOME CUMULUS HAVE DEVELOPED THIS AFTERNOON BUT WILL  
QUICKLY DISSIPATE WITH SUNSET. LOWS TONIGHT ARE STILL EXPECTED  
TO GENERALLY FALL TO A -5 TO 5 ABOVE RANGE. IT LIKELY WILL BE  
HARD FOR WINDS TO DECOUPLE TONIGHT, THOUGH A NARROW SURFACE  
RIDGE AXIS WILL EXTEND OUT OF THE OHIO VALLEY AND TOWARDS  
CENTRAL AND EAST-CENTRAL OHIO. WITH AT LEAST SOME FRESH SNOW IN  
THAT AREA, IT'S POSSIBLE SOME LOWER-LYING AREAS DECOUPLE AND SEE  
TEMPERATURES TANK LOCALLY MORE THAN EXPECTED. WIND CHILLS WILL  
GENERALLY BOTTOM OUT IN THE -14 TO -22 RANGE TONIGHT, WHICH IS  
SOLIDLY WITHIN THE "ADVISORY" REALM.  
 
A SHORTWAVE AND SURFACE COLD FRONT WILL MOVE ACROSS THE REGION  
FROM WEST TO EAST ON TUESDAY, BRINGING A MODEST INCREASE IN  
SYNOPTIC MOISTURE AND SOME LIFT TO THE REGION. SOME MID-LEVEL  
CLOUDS SHOULD SPREAD IN LATE TONIGHT INTO TUESDAY MORNING AS  
PVA/HEIGHT FALLS AHEAD OF THE SHORTWAVE AND MODEST LOW TO MID-  
LEVEL WARM AIR ADVECTION/ISENTROPIC LIFT ARRIVE. SOME VERY LIGHT  
SNOW COULD BREAK OUT AHEAD OF THE COLD FRONT TUESDAY DUE TO THE  
ISENTROPIC LIFT. THE MORE INTERESTING FEATURE WILL BE THE COLD  
FRONT ITSELF. DECENT LOW-LEVEL CONVERGENCE, ALONG WITH  
SUFFICIENT LOW-LEVEL MOISTURE AND STEEP LOW-LEVEL LAPSE RATES,  
WILL YIELD POTENTIAL FOR SNOW SHOWERS ALONG AND JUST AHEAD OF  
THE FRONT. THIS FORECASTER WAS A BIT AMUSED TO SEE FORECAST  
SOUNDINGS DEPICTING JUST A LITTLE BIT OF CAPE AHEAD OF THE FRONT  
ON TUESDAY IN SUCH A COLD AIRMASS. IN RESPONSE, HIT MOST OF THE  
AREA WITH CHANCE (30-50%) POPS FOR A RATHER BRIEF WINDOW FROM  
WEST TO EAST ON TUESDAY. HAVE LOWER POPS (10-20%) IN THE TOLEDO  
AREA AND ACTUALLY INCREASE TO LIKELY (60-70%) FROM OUR EASTERN  
COUPLE TIERS OF OHIO COUNTIES INTO NORTHWEST PA. SNOW AMOUNTS  
WILL GENERALLY BE LESS THAN 0.5" WEST OF I-77, WITH LOCALLY UP  
TO AN INCH POSSIBLE FARTHER EAST. THERE COULD BE A BRIEF PERIOD  
OF TRAVEL ANNOYANCES ON TUESDAY WITH ANY SNOW. WHILE AMOUNTS ARE  
LIGHT, IT WILL BE QUITE COLD AND ANY MEASURABLE SNOW WILL STICK  
TO ROADS. ALSO, THERE COULD BE A CONVECTIVE COMPONENT ALONG THE  
FRONT, LEADING TO BRIEF INTENSITY WITH SOME SNOW SHOWERS. GIVEN  
THE COLD AND DRY ARCTIC AIRMASS, MOST OR ALL OF THE CLOUDS AND  
SNOW GROWTH WILL TAKE PLACE ABOVE THE PREFERRED DENDRITIC GROWTH  
ZONE ON TUESDAY. THIS WILL LIKELY MEAN SMALLER FLAKES WHICH  
WON'T HAVE AN EXCEPTIONALLY HIGH SNOW TO LIQUID RATIO, BUT COULD  
EFFECTIVELY REDUCE VISIBILITY. HIGHS ON TUESDAY WILL GENERALLY  
WARM TO A 5 TO 12 DEGREE RANGE, WITH A BIT OF A NON-DIURNAL  
TREND POSSIBLE IN NORTHWEST OH WITH COLD AIR ADVECTION KICKING  
IN DURING THE AFTERNOON BEHIND THE FRONTAL PASSAGE. WIND CHILLS  
RECOVER A FEW DEGREES TUESDAY AFTERNOON, THOUGH WILL STRUGGLE TO  
WARM ABOVE -5 TO -15.  
 
THE FRONT EXITS EAST TUESDAY NIGHT WITH HIGH PRESSURE BUILDING  
QUICKLY OUT OF THE OHIO VALLEY, LEADING TO A DRY AND MAINLY  
CLEAR NIGHT. LAKE EFFECT WILL TRY TO BRIEFLY COME BACK ONSHORE  
INTO ERIE COUNTY, PA RIGHT BEHIND THE FRONT BEFORE LIFTING BACK  
OVER THE LAKE. DON'T WANT TO ENTIRELY RULE OUT A QUICK INCH OR  
SO OF "DUSTY" SNOW IF THAT HAPPENS. OTHERWISE, THE BIG STORY  
WILL BE THE COLD. CLEARING SKIES, RATHER FRESH SNOW PACK ACROSS  
THE EASTERN TWO-THIRDS OF OUR AREA, A "REFRESHED" COLD AIRMASS  
RIGHT BEHIND THE FRONT, AND SLACKENING PRESSURE GRADIENT WILL  
SET THE STAGE FOR SURFACE TEMPERATURES TO PLUMMET TUESDAY NIGHT.  
HAVE AIR TEMPERATURES FALLING TO -5 TO -15 IN GENERAL, SLIGHTLY  
WARMER NEAR THE EASTERN LAKESHORE. LIGHTER WINDS WILL WORK  
AGAINST EXTREMELY COLD WIND CHILLS, THOUGH IT MAY BE HARD FOR  
WINDS TO GO COMPLETELY CALM. WIND CHILLS WILL BOTTOM OUT -20 TO 25  
ACROSS MOST OF THE AREA, AND STILL CAN'T RULE OUT A POTENTIAL  
NEED TO EVENTUALLY UPGRADE PARTS OF THE AREA TO AN EXTREME COLD  
WARNING (CRITERIA IS -25F). WITH DEW POINTS EXPECTED TO DROP TO  
THE -15 TO -20 RANGE, ROOM IS THERE FOR LOW-LYING AND LESS-  
URBAN AREAS TO DROP TO NEAR OR BELOW -20 DEGREES IF THEY'RE ABLE  
TO DECOUPLE. HARD TO GET THIS IN THE FORECAST GRIDS, THOUGH DID  
LOWER TEMPERATURES FROM THE PRIOR FORECAST A BIT, ESPECIALLY IN  
LOWER-LYING AREAS WHERE WE HAVE RELATIVELY LIGHTER WINDS IN THE  
FORECAST. INFRASTRUCTURE ISSUES CAUSED BY THE COLD WILL PEAK  
TUESDAY NIGHT-EARLY WEDNESDAY.  
 
 
   
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/  
 
SLOWLY WILL BE COMING OUT OF THE COLDEST AIR OF THE SEASON FOR THE  
AREA, WITH TEENS WEDNESDAY AND A SIGNIFICANT JUMP THURSDAY BACK INTO  
THE 20S WITH SOME BRIEF LOW LEVEL WARM AIR ADVECTION. 850MB  
TEMPERATURES CLIMB INTO THE -10C RANGE WEDNESDAY AS THE CANADIAN  
HIGH PRESSURE SYSTEM THAT BROUGHT THE COLD AIRMASS SHIFTS EAST OF  
THE CWA AND A CLIPPER SYSTEM TRACKS INTO THE NORTHERN GREAT LAKES.  
EXPECTING A COLD FRONT SHORTLY THEREAFTER FROM THE SURFACE LOW OVER  
THE NORTHERN LAKES ON THURSDAY BRINGING A FEW SNOW SHOWERS WITH IT  
ALONG WITH A WEAK REINFORCEMENT TO THE CHILLY AIR THAT HAS PLAGUED  
THE REGION FOR THE MONTH OF JANUARY. THE PATTERN IS VERY PROGRESSIVE  
WITH THAT COLD FRONT OFF TO THE EAST VERY QUICKLY AND HIGH PRESSURE  
BACK INTO PLAY FOR THURSDAY NIGHT. SOME QUESTIONS IN THE FORECAST AT  
THIS POINT WITH THE POTENTIAL FOR LAKE EFFECT BEHIND THE COLD FRONT.  
FAVORABLE LAKE EFFECT SNOW WIND DIRECTIONS ARE NOT A SLAM DUNK AND  
MIGHT BE A LITTLE MORE VARIABLE DURING THE THURSDAY NIGHT PERIOD, SO  
ONLY CARRYING LOW POPS/SNOW AMOUNTS AT THIS TIME, BUT WILL BE  
SOMETHING TO WATCH GOING FORWARD.  
 
 
   
LONG TERM /FRIDAY THROUGH MONDAY/  
 
PATTERN ALOFT BECOMES MORE ZONAL, WHICH WILL ALLOW TEMPERATURES TO  
PUSH TOWARDS THE FREEZING MARK HEADING INTO THE WEEKEND AS MORE  
MODERATE AIR THAT HAS BEEN PINNED WELL TO THE SOUTH IS ALLOWED TO  
CREEP BACK NORTHWARD. NO MAJOR SYSTEMS ON THE HORIZON, BUT COULD SEE  
A COUPLE WEAK TROUGHS ALOFT PUSH THROUGH IN THE LONG TERM PERIOD,  
LARGELY BENIGN. STILL GOING TO BE LARGELY BELOW NORMAL FOR  
TEMPERATURES AS WE HEAD INTO THE LAST WEEK OF JANUARY.  
 
 
   
AVIATION /18Z MONDAY THROUGH SATURDAY/  
 
MAINLY VFR THIS AFTERNOON OUTSIDE OF ERI, WHERE A BAND OF  
MODERATE TO HEAVY LAKE EFFECT SNOW IS REDUCING VSBY TO AS LOW AS  
1/4SM. THIS BAND SHOULD LIFT NORTH OF ERI 19-20Z, BRINGING  
SIGNIFICANT IMPROVEMENT. OTHERWISE, SOME SCATTERED CUMULUS IN  
THE 025-040 RANGE, ALLEGEDLY BKN AT YNG. THESE CUMULUS SHOULD  
DISSIPATE WITH SUNSET THIS EVENING LEADING TO MAINLY CLEAR SKIES  
INTO TONIGHT. A WEAK DISTURBANCE AND COLD FRONT WILL CROSS FROM  
WEST TO EAST ON TUESDAY. EXPECT A PERIOD OF LOW VFR TO MVFR  
CEILINGS, ALONG WITH SNOW SHOWERS WHICH COULD PRODUCE IFR VSBY  
FOR A BRIEF PERIOD, ESPECIALLY FROM CLE-MFD POINTS EAST. BEGAN  
INTRODUCING MVFR CIGS AND VSBY IN SNOW SHOWERS, WITH PROB30S AT  
SOME SITES FOR BRIEF IFR VSBY. SOUTHWEST WINDS AT 8 TO 15 KNOTS  
WITH GUSTS 20 TO 25 KNOTS THIS AFTERNOON SLACKEN TO 5 TO 12  
KNOTS (WITH NO GUSTS TONIGHT). WINDS GRADUALLY VEER A BIT MORE  
WESTERLY BEHIND THE FRONT ON TUESDAY AND INCREASE TO A 10 TO 15  
KNOT RANGE, WITH SOME 20 TO 25 KNOT GUSTS RETURNING.  
 
OUTLOOK...MAINLY VFR EXPECTED TUESDAY NIGHT THROUGH EARLY  
THURSDAY. NON-VFR POSSIBLE IN SCATTERED SNOW SHOWERS THURSDAY.  
 
 
   
MARINE  
 
FREEZING SPRAY IN THE OPEN WATERS EAST OF AVON POINT CONTINUES TO BE  
A POTENTIAL HAZARD THROUGH TUESDAY NIGHT WITH SOUTHWEST WIND GUSTS  
REACHING 25-35KTS. THE HEAVY FREEZING SPRAY WARNING REMAINS IN  
EFFECT DURING THIS PERIOD. AS THE LAKE BECOMES LESS TURBULENT  
THROUGH MID WEEK AND INTO THE END OF THE WEEK, CONTINUED ICE  
COVERAGE IS FAVORABLE WITH THE COLDEST AIRMASS OF THE SEASON  
CURRENTLY IN PLACE. MAINLY ICED OVER FROM VERMILION WEST, ALTHOUGH  
LOTS OF ICE SHIFTING STILL TAKING PLACE WITH WIND DIRECTION CHANGES.  
WINDS DO NOT COME DOWN BELOW 15KTS UNTIL THURSDAY.  
 
SMALL CRAFT ADVISORY ISSUANCE HAS BEEN SUSPENDED UNTIL FURTHER  
NOTICE FOR NEARSHORE WATERS FROM MAUMEE BAY TO RIPLEY DUE TO  
EXTENSIVE ICE COVER.  
 
 
   
CLIMATE  
 
ARCTIC AIR PERSISTS THROUGH WEDNESDAY. THE COLDEST TEMPERATURES  
ARE EXPECTED LATE TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING  
WITH FORECAST TEMPERATURES APPROACHING RECORD LOWS FOR 1/22.  
BELOW ARE THE CURRENT RECORD LOW TEMPERATURES FOR 1/21-22.  
 
DATE TOLEDO MANSFIELD CLEVELAND AKRON YOUNGSTOWN ERIE  
01-21 -20(1984) -19(1985) -17(1985) -24(1985) -20(1985) -16(1985)  
01-22 -12(1936) -10(1936) -10(1936) -13(1936) -9(2022) -7(1970)  
 
 
   
CLE WATCHES/WARNINGS/ADVISORIES  
 
OH...COLD WEATHER ADVISORY UNTIL 10 AM EST WEDNESDAY FOR OHZ003-  
006>014-017>023-027>033-036>038-047-089.  
PA...COLD WEATHER ADVISORY UNTIL 10 AM EST WEDNESDAY FOR PAZ001>003.  
WINTER WEATHER ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR  
PAZ001-002.  
MARINE...HEAVY FREEZING SPRAY WARNING UNTIL 1 AM EST WEDNESDAY FOR  
LEZ166>169.  
 
 
 
 
 
SYNOPSIS...SULLIVAN  
NEAR TERM...SULLIVAN  
SHORT TERM...26  
LONG TERM...26  
AVIATION...SULLIVAN  
MARINE...26  
CLIMATE...  
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