553  
FXUS61 KCLE 212316  
AFDCLE  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE CLEVELAND OH  
716 PM EDT TUE MAY 21 2019  
   
SYNOPSIS
 
 
HIGH PRESSURE WILL SHIFT EAST TONIGHT AND A WARM FRONT WILL  
LIFT NORTH ACROSS THE AREA WEDNESDAY AFTERNOON. THE COLD FRONT  
WITH THIS SYSTEM WILL CROSS THE AREA THURSDAY. FRIDAY NIGHT,  
AND THROUGH THE HOLIDAY WEEKEND, THE POSITION OF A FRONT WILL  
WAVER ACROSS THE REGION AND BE THE FOCUS FOR CONVECTION.  
 

 
   
NEAR TERM /THROUGH WEDNESDAY NIGHT/
 
 
WEAK WARM ADVECTION AT 850/700 MB WILL CONTINUE PRODUCE LIFT  
OVER THE REGION. THE LOWER LEVELS OF THE ATMOSPHERE ARE FAIRLY  
DRY SO ANYTHING REACHING THE GROUND WILL BE A BRIEF PERIOD OF  
VERY LIGHT RAIN OR SPRINKLES. THE AREA OF STRONGEST WARM  
ADVECTION IS ACROSS INDIANA INTO SW OH. CURRENT THINKING IS THAT  
THIS DOES NOT REACH THE SOUTHWESTERN CWA THROUGH THE EVENING.  
 
PREVIOUS DISCUSSION...  
A FEW SPRINKLES REMAIN ACROSS THE WESTERN COUNTIES EAST TO  
AKRON THIS AFTERNOON AND WILL CONTINUE TO BE THE CASE THROUGH  
APPROX DARK. PRECIP WILL CONTINUE TO STRUGGLE AS THE RIDGE  
BUILDS OVERHEAD TONIGHT. THE THICK CLOUD COVER IS EXPECTED FOR  
THE NIGHT WITH ONLY NW PA GETTING SOME THINNING AT TIMES. LOWS  
WILL AGAIN BE IN THE 40S, BUT WILL LIKELY NOT SEE ANY UPPER 30S  
WITH THE EXPECTED CLOUD COVER AND THE FLOW BEGINNING TO VEER.  
 
THE WARM FRONT LIFTS ACROSS THE AREA WEDNESDAY. LINGERING  
CONVECTION FROM THE WEST WILL BE REACHING NORTHWEST OH IN THE  
MORNING. EXPECTING COVERAGE TO BE LIMITED AS THIS AREA GETS INTO  
OUR WESTERN COUNTIES WITH AN UPTICK IN COVERAGE AND DEVELOPMENT  
GOING INTO THE AFTERNOON AND EARLY EVENING EAST OF I-71. AREA  
WILL BE ON THE WESTERN PERIPHERY OF THE RIDGE. ENOUGH LOW AND  
MID LEVEL FLOW AND DIURNAL INSTABILITY WILL AID IN THE STORM  
DEVELOPMENT. HAVE CHOSEN SCATTERED AND LIKELY WORDING. AGREE  
WITH THE MARGINAL SEVERE RISK IDENTIFIED BY SPC. TEMPERATURES  
WILL WARM WELL INTO THE 70S (ESPECIALLY WEST AND SOUTH). THE  
GRADIENT FLOW IS STRONG ENOUGH TO INHIBIT A LAKE BREEZE.  
 
CONVECTION SHOULD BE CONFINED TO THE EVENING HOURS ACROSS THE  
EAST/SOUTHEAST COUNTIES WITH THE REMAINDER OF THE NIGHT FAIR AND  
MILD IN THE WARM SECTOR. LOWS WILL BE IN THE UPPER 50S/LOW 60S.  
 

 
   
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/
 
 
ACTIVE UPPER LEVEL PATTERN IN PLACE ACROSS THE UNITED STATES.  
UPPER LEVEL TROUGH WILL DIVE INTO THE WESTERN UNITED STATES  
THURSDAY INTO FRIDAY FORCING AMPLIFICATION OF AN UPPER LEVEL  
RIDGE OVER THE EASTERN HALF OF THE COUNTRY. THE RIDGE WILL  
EXTEND NORTH FROM UPPER LEVEL HIGH PRESSURE OVER SOUTHERN  
GEORGIA BY FRIDAY. LOW PRESSURE WILL MOVE EAST ACROSS THE  
NORTHERN GREAT LAKES IN RESPONSE TO UPPER LEVEL SHORTWAVE TROUGH  
MOVING QUICKLY EAST ACROSS THE AREA. THIS LOW WILL FORCE A COLD  
FRONT EAST ACROSS THE AREA THURSDAY. LIMITED MOISTURE WITH THE  
FRONT IS EXPECTED BUT THE THREAT FOR SHOWERS AND THUNDERSTORMS  
IS ALSO POSSIBLE. THERE IS THE THREAT FOR SOME OF THE  
THUNDERSTORMS TO BECOME SEVERE THURSDAY AHEAD OF THE COLD FRONT  
AS DESTABILIZATION TAKES PLACE. DEWPOINT TEMPERATURES WILL CLIMB  
UP INTO THE MIDDLE TO UPPER 60S THURSDAY AND IN WARM AIR  
ADVECTION HIGHS WILL TOP OUT IN THE LOWER TO MIDDLE 80S. COLD  
FRONT WILL BE EAST OF THE AREA THURSDAY NIGHT WITH RELATIVELY  
WEAK COLD AIR ADVECTION. FRONT SHOULD KNOCK TEMPERATURES DOWN  
INTO THE UPPER 50S TO LOWER 60S ACROSS MUCH OF THE AREA.  
NORTHEAST PORTIONS SHOULD BE IN THE LOWER TO MIDDLE 50S. HIGH  
PRESSURE WILL SCOOT BY ACROSS THE AREA FRIDAY AND ANOTHER WARM  
FRONT WILL BEGIN TO APPROACH FROM THE SOUTHWEST. THIS WILL BRING  
A SURGE OF WARM AIR BACK TO THE REGION ALONG WITH INCREASING  
DEWPOINT TEMPERATURES BACK INTO THE MIDDLE 50S NORTHEAST TO THE  
LOWER TO MIDDLE 60S SOUTHWEST.  
 

 
   
LONG TERM /SATURDAY THROUGH TUESDAY/
 
 
UPPER LEVEL RIDGE IS EXPECTED TO SHIFT EAST AND FLATTEN ACROSS  
THE GREAT LAKES SATURDAY AND SUNDAY. MEANWHILE, AN UPPER LEVEL  
LOW PRESSURE SYSTEM WILL DIVE INTO THE WEST COAST AND CAUSE THE  
UPPER LEVEL RIDGE TO AMPLIFY OVER THE EASTERN TWO THIRDS OF THE  
UNITED STATES BY TUESDAY. YET ANOTHER LOW PRESSURE AND  
ASSOCIATED SHORTWAVE WILL MOVE EAST ACROSS CENTRAL ONTARIO,  
CANADA SATURDAY. THIS WILL FORCE A COLD FRONT EAST ACROSS THE  
AREA SATURDAY NIGHT. LIMITED MEAN RELATIVE HUMIDITY WILL BE  
ASSOCIATED WITH THE BOUNDARY BUT THREAT FOR SHOWERS AND  
THUNDERSTORMS ARE EXPECTED AS DESTABILIZATION TAKES PLACE ONCE  
AGAIN. DEWPOINTS ON SATURDAY COULD SURGE WELL INTO THE UPPER 60S  
AGAIN. HIGH PRESSURE WILL MOVE INTO THE GREAT LAKES SUNDAY BUT  
THE FEATURE WASHES OUT AND LITTLE IN THE WAY OF CHANGE OF AIR  
MASS WILL TAKE PLACE. A FAST MOVING UPPER LEVEL SHORTWAVE TROUGH  
WILL MOVE EAST INTO THE NORTHERN GREAT LAKES MONDAY FORCING  
SURFACE LOW PRESSURE TO DEVELOP IN THE NORTHERN LAKES. THIS LOW  
WILL THEN FORCE A COLD FRONT SOUTHEAST ACROSS THE AREA MONDAY  
FOLLOWED BY HIGH PRESSURE INTO THE EARLY PART OF THE WEEK.  
TEMPERATURES WILL BE WELL INTO THE 80S FOR HIGHS SATURDAY AND  
GRADUALLY COOL TO THE MIDDLE AND UPPER 70S MONDAY AND TUESDAY.  
LOWS IN THE UPPER 50S TO AROUND 60.  
 

 
   
AVIATION /00Z WEDNESDAY THROUGH SUNDAY/
 
 
WEAK WARM ADVECTION AT 850/700 MB WILL CONTINUE PRODUCE LIFT  
OVER THE REGION. THE LOWER LEVELS OF THE ATMOSPHERE ARE FAIRLY  
DRY SO ANYTHING REACHING THE GROUND WILL BE A BRIEF PERIOD OF  
VERY LIGHT RAIN OR SPRINKLES. THE AREA OF STRONGEST WARM  
ADVECTION IS ACROSS INDIANA INTO SW OH. CURRENT THINKING IS THAT  
THIS DOES NOT REACH THE SOUTHWESTERN CWA THROUGH THE EVENING.  
SO EXPECT TO SEE CEILINGS GRADUALLY SPREAD OVER ALL THE AREA  
OVERNIGHT AND SLOWLY LOWER AS A WARM FRONT APPROACHES. A FEW  
SHOWERS MAY REACH NW OHIO IN THE STRONGER WARM ADVECTION IN THE  
MORNING. AS THE WARM FRONT MOVES ACROSS THE AREA WEDNESDAY  
AFTERNOON EXPECT TO SEE SHOWERS AND THUNDERSTORMS REDEVELOP.  
MVFR/IFR CONDITIONS AND A FEW STRONGER WIND GUSTS TO 40 KNOTS  
MAY ACCOMPANY THE STRONGEST THUNDERSTORMS.  
 
WINDS WILL BE MOSTLY FROM THE EAST OVERNIGHT AT 5 TO 12 KNOTS.  
AS THE WARM FRONT LIFTS ACROSS THE AREA WINDS WILL SHIFT TO THE  
SOUTH AND SOUTHWEST. SPEEDS WILL GENERALLY BE 10 TO 15 KNOTS  
WITH A FEW GUSTS IN THE 20 TO 25 KNOT RANGE.  
 
OUTLOOK...NON-VFR POSSIBLE WEDNESDAY EVENING, THURSDAY/THURSDAY  
NIGHT, SATURDAY AND SUNDAY.  
 

 
   
MARINE
 
 
EAST TO SOUTHEAST WINDS WILL DEVELOP OVERNIGHT CAUSING WATER  
LEVELS TO RISE ONCE AGAIN ON THE WESTERN BASIN OF THE LAKE.  
POSSIBLE SHORE LINE FLOODING COULD OCCUR LATE TONIGHT INTO  
TOMORROW MORNING. A LAKESHORE FLOOD WATCH HAS BEEN ISSUED FOR 2  
AM THROUGH ABOUT 10 AM TOMORROW. EVENT SHOULD BE SHORT LIVED AS  
FLOW SHIFTS TO MORE SOUTHEASTERLY CUTTING DOWN ON THE FETCH.  
OTHERWISE, WINDS WILL GRADUALLY SHIFT TO WESTERLY THURSDAY AND  
INCREASE IN SPEED TO ABOUT 15 TO 25 KNOTS AND THEN DIMINISH TO  
LIGHT AND VARIABLE BY THURSDAY NIGHT AND FRIDAY. RETURN  
SOUTHERLY FLOW DEVELOPS FRIDAY NIGHT BUT LIGHT AND THEN  
INCREASES TO 15 TO 25 KNOTS AGAIN SATURDAY FROM THE SOUTHWEST.  
FLOW WILL GRADUALLY BECOME LIGHT AND VARIABLE BY SUNDAY.  
 

 
   
CLE WATCHES/WARNINGS/ADVISORIES
 
 
OH...LAKESHORE FLOOD WATCH FROM 2 AM EDT WEDNESDAY THROUGH  
WEDNESDAY MORNING FOR OHZ003-007>009.  
PA...NONE.  
MARINE...NONE.  
 

 
 

 
SYNOPSIS...OUDEMAN  
NEAR TERM...MM/OUDEMAN  
SHORT TERM...LOMBARDY  
LONG TERM...LOMBARDY  
AVIATION...MM  
MARINE...LOMBARDY  
 
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