549  
FXUS61 KCLE 091339  
AFDCLE  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE CLEVELAND OH  
939 AM EDT SUN AUG 9 2020  
   
SYNOPSIS
 
 
HIGH PRESSURE CENTERED OVER THE OHIO VALLEY WILL CONTINUE MOVING  
SOUTHEAST TODAY. A WARM FRONT WILL LIFT NORTHEASTWARD ACROSS THE  
REGION ON MONDAY. A COLD FRONT WILL CROSS THE AREA ON TUESDAY.  
HIGH PRESSURE WILL RETURN TO THE REGION ON WEDNESDAY.  
 

 
   
NEAR TERM /THROUGH MONDAY/
 
 
CURRENT FORECAST IS ON TRACK. ONLY MADE MINOR CHANGERS TO CLOUD  
COVER AND HOURLY TEMPERATURES TO REFLECT CURRENT TRENDS.  
 
PREVIOUS DISCUSSION...  
SUNDAY WILL FEATURE THE LAST QUIET WEATHER DAY OF THIS STRETCH  
WITH HIGH PRESSURE SLIDING SOUTHEAST OF THE AREA. SOUTHWEST FLOW  
WILL RETURN TO THE REGION ON THE WEST SIDE OF THIS SYSTEM,  
ALLOWING FOR TEMPERATURES AND MOISTURE TO INCREASE ACROSS THE  
REGION. UPPER RIDGING OVER THE AREA WILL ALLOW FOR DRY  
CONDITIONS, BUT THE INFLUX OF MOISTURE WILL ALLOW FOR SOME  
DIURNAL CUMULUS TO BE THE MAIN PROBLEM OF THE DAY. HIGH  
TEMPERATURES WILL BE SEVERAL DEGREES WARMER THAN SATURDAY AND  
SOME LOCATIONS MAY SEE 90 DEGREES FOR THE FIRST TIME IN SEVERAL  
WEEKS. OVERNIGHT LOWS WILL REMAIN WARM IN THE 60S WITH SOME  
CLOUDS ENTERING THE REGION AND WARMER DAYTIME HIGHS.  
 
A WARM FRONT WILL APPROACH THE AREA ON MONDAY AND WILL PROMOTE  
WARM TEMPERATURES ONCE AGAIN WITH PERHAPS MORE WIDESPREAD LOWER  
90S ACROSS THE REGION. THE MAIN QUESTION WITH THIS FRONT IS  
PRECIPITATION POTENTIAL. THE SUPPORTING SHORTWAVE TROUGH APPEARS  
TO HAVE SLOWED THROUGH THE GREAT LAKES REGION AND THEREFORE, THE  
BEST TIMING OF RAIN HAS SHIFTED SLIGHTLY LATER IN THE DAY. HAVE  
POPS INCREASING THROUGH THE AFTERNOON HOURS ON MONDAY, BUT THE  
BEST RAIN CHANCES APPEAR TO BE BEYOND THE NEAR TERM FORECAST  
PERIOD FOR MUCH OF THE FORECAST AREA. SOME INSTABILITY OVER THE  
REGION WILL ALLOW FOR SOME THUNDER POTENTIAL AND HAVE THUNDER  
MENTIONED FOR MONDAY AFTERNOON.  
 

 
   
SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/
 
 
BY THE BEGINNING OF THE SHORT TERM FORECAST PERIOD, AN UPPER LEVEL  
RIDGE THAT PERSISTED OVER THE AREA DURING THE WEEKEND WILL BEGIN TO  
BE REPLACED BY AN UPPER LEVEL LONGWAVE TROUGH, RESULTING IN UPPER  
WESTERLY FLOW ACROSS THE AREA. MULTIPLE SHORTWAVE DISTURBANCES ARE  
EXPECTED TO MOVE ALONG THE PERIPHERY OF THIS LONGWAVE TROUGH AND  
IMPACT THE CWA THROUGHOUT THE WEEK. BEGINNING ON MONDAY NIGHT, A  
FRONTAL SYSTEM APPROACHES THE AREA FROM THE WEST AS THE RIDGE EXITS  
THE AREA TO THE EAST. AHEAD OF THE COOL FRONT MOVING ACROSS THE AREA  
ON TUESDAY, WINDS WILL BE FROM THE SOUTHWEST DUE TO THE BACK EDGE OF  
THE HIGH PRESSURE SYSTEM. THIS WILL ALLOW FOR AMPLE MOISTURE  
ADVECTION INTO THE REGION FROM THE GULF OF MEXICO, RESULTING IN THE  
RETURN OF HUMID CONDITIONS. THE COOL FRONT SHOULD MOVE THROUGH THE  
AREA BY TUESDAY AFTERNOON/EVENING. SCATTERED SHOWERS AND  
THUNDERSTORMS ARE POSSIBLE MONDAY EVENING THROUGH TUESDAY EVENING  
WITH THE APPROACH AND PASSAGE OF THE FRONT. CURRENT MODELS HAVE  
LIMITED VERTICAL WINDS SHEAR ASSOCIATED WITH THIS SYSTEM, HOWEVER  
MODERATE FORECAST INSTABILITY VALUES, A VERY MOIST ATMOSPHERE, AND  
SOME MODELS SUGGESTING UPPER LEVEL SUPPORT WITH A SHORT WAVE TROUGH  
MAY ALLOW FOR A FEW PULSE THUNDERSTORMS TO BECOME STRONG, WITH  
STRONG WINDS BEING THE PRIMARY THREAT.  
 
ANOTHER WEAK HIGH PRESSURE IS EXPECTED TO BUILD INTO THE AREA  
TUESDAY NIGHT INTO WEDNESDAY. OPTED TO KEEP CHANCE OF SCATTER  
SHOWERS AND THUNDERSTORMS IN THE FORECAST ON WEDNESDAY AS LINGERING  
MOISTURE AND DIURNAL INSTABILITY CANNOT COMPLETELY RULE THEM OUT.  
HIGH TEMPERATURES ON TUESDAY AND WEDNESDAY WILL BE IN THE LOW TO MID  
80S, WITH HUMIDITY RETURNING ACROSS THE AREA. LOW TEMPERATURES  
OVERNIGHT WILL DIP DOWN INTO THE MID 60S.  
 

 
   
LONG TERM /THURSDAY THROUGH SATURDAY/
 
 
DURING THE LONG TERM PERIOD, THE LONG WAVE TROUGH WILL CONTINUE TO  
SLOWLY PROGRESS EASTWARD AS EMBEDDED SHORTWAVE TROUGHS ALSO CONTINUE  
TO PROPOGATE EASTWARD THROUGHOUT THE PERIOD. BEHIND THIS TROUGH, A  
RIDGE OF HIGH PRESSURE BEGINS TO BUILD ACROSS THE EASTERN US,  
HOWEVER A LOW PRESSURE BUILDING IN THE MISSISSIPPI VALLEY IS  
EXPECTED TO UNDERCUT THIS RIDGE DURING THE LONG TERM FORECAST  
PERIOD. OVER OUR AREA, IT IS FORECAST THAT A WEAK HIGH PRESSURE  
REMAINS OVER THE AREA, HOWEVER MODELS BEGIN TO DIVERGE TOWARDS THE  
END OF THE PERIOD WITH HANDLING THIS NEXT SYSTEM. KEPT CHANCE OF  
POPS IN FOR THE MAJORITY OF THE FORECAST PERIOD DUE TO THE DIURNAL  
CYCLE INTERACTING WITH THE LINGERING MOISTURE OVER THE AREA. HIGH  
TEMPERATURES DURING THIS PERIOD WILL BE IN THE MID 80S WITH  
OVERNIGHT LOWS NEAR THE MID TO UPPER 60S.  
 

 
   
AVIATION /12Z SUNDAY THROUGH THURSDAY/
 
 
HIGH PRESSURE CENTERED SOUTHEAST OF THE AIRSPACE WILL ALLOW FOR  
VFR CONDITIONS TO CONTINUE THROUGH TAF PERIOD. SOME SPOTTY  
CIRRUS HAS BEEN OVERHEAD THIS MORNING AND AS HIGH PRESSURE  
CONTINUES MOVING SOUTHEAST, BETTER MOISTURE WILL ENTER THE  
REGION AND DIURNAL CUMULUS SHOULD FORM OVER THE REGION THIS  
AFTERNOON. ANY OF THESE LOWER CLOUDS SHOULD DISSIPATE LATE THIS  
EVENING. SHOWERS AND THUNDERSTORMS TO THE WEST OF THE REGION  
MAY ALLOW FOR SOME CIRRUS CLOUDS TO MOVE IN TONIGHT. WINDS WILL  
BE GENERALLY SOUTHWESTERLY THROUGH THE PERIOD AS HIGH PRESSURE  
MOVES TO THE SOUTHEAST.  
 
OUTLOOK...NON-VFR POSSIBLE WITH AFTERNOON SHOWERS AND THUNDERSTORMS  
MONDAY THROUGH WEDNESDAY.  
 

 
   
MARINE
 
 
HIGH PRESSURE WILL CONTINUE TO PERSIST OVER LAKE ERIE FOR SUNDAY AND  
PART OF MONDAY. WINDS TODAY WILL BE FROM THE SOUTHWEST AT 5 TO 10  
KNOTS IN THE WESTERN BASIN AND 10 TO 15 KNOTS IN THE EASTERN BASIN.  
BY SUNDAY NIGHT, WINDS WILL BECOME MORE SOUTHERLY AND WEAKEN TO 5 TO  
10 KNOTS ACROSS THE ENTIRE LAKE AND PERSIST UNTIL MONDAY AFTERNOON  
AS THE HIGH PRESSURE SHIFTS TOWARDS THE SOUTHERN APPALACHIANS. A  
COLD FRONT SHOULD MOVE ACROSS LAKE ERIE TUESDAY AFTERNOON, CAUSING  
WINDS TO BECOME MORE WESTERLY. AHEAD OF AND WITH THE PASSAGE OF THIS  
FRONT, SHOWERS AND THUNDERSTORMS ARE POSSIBLE, WHICH HAVE THE  
POSSIBILITY OF PRODUCING LOCALLY STRONGER WINDS AND HIGHER WAVES.  
HIGH PRESSURE IS EXPECTED TO BUILD BACK IN ACROSS THE AREA ON  
WEDNESDAY INTO THURSDAY, ALLOWING WINDS TO BECOME NORTHEASTERLY AT 5  
TO 15 KNOTS. THROUGHOUT THE ENTIRE FORECAST PERIOD, WAVES WILL  
LIKELY BE BETWEEN 1 TO 3 FEET. NO HEADLINES ARE EXPECTED AT THIS  
TIME.  
 

 
   
CLE WATCHES/WARNINGS/ADVISORIES
 
 
OH...NONE.  
PA...NONE.  
MARINE...NONE.  
 

 
 

 
SYNOPSIS...SEFCOVIC  
NEAR TERM...MM/SEFCOVIC  
SHORT TERM...CAMPBELL  
LONG TERM...CAMPBELL  
AVIATION...SEFCOVIC  
MARINE...CAMPBELL  
 
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