529  
FXUS61 KILN 270611  
AFDILN  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE WILMINGTON OH  
111 AM EST SAT FEB 27 2021  
   
SYNOPSIS
 
 
LOW PRESSURE MOVING THROUGH THE OHIO AND TENNESSEE VALLEYS WILL  
BRING PRECIPITATION TO THE REGION THIS EVENING THROUGH THE  
OVERNIGHT. ANOTHER, STRONGER WAVE OF LOW PRESSURE WILL PROVIDE  
ADDITIONAL RAIN FOR THE LATTER HALF OF THE WEEKEND BEFORE HIGH  
PRESSURE CAUSES DRY WEATHER TO RETURN EARLY NEXT WORK WEEK.  
 

 
   
NEAR TERM /UNTIL 6 AM THIS MORNING/
 
 
MOST OF THE TRADITIONAL SHOWER-TYPE ACTIVITY HAS EXITED THE ILN  
FA, LEAVING IN ITS WAKE SOME PATCHY DRIZZLE AND VERY LIGHT RAIN  
THROUGH THE FIRST PART OF THE OVERNIGHT PERIOD. MOST SPOTS WON'T  
SEE MUCH ADDITIONAL RAIN UNTIL AFTER 3 AM OR SO WHEN SHOWERS  
ALONG/JUST AHEAD OF THE FRONT ITSELF MOVE BACK INTO THE AREA  
FROM THE WEST. THE TIME WINDOW FOR FAVORED SHOWERS FOR ANY ONE  
LOCATION WILL BE ON THE ORDER OF AN HOUR OR TWO AS THE FRONT  
PROGRESSES WEST TO EAST THROUGH THE AREA BETWEEN 3 AM AND 8 AM.  
WILL ALSO SEE A RESURGENCE OF RAIN IN THE FAR SOUTHEAST,  
INCLUDING THE LOWER SCIOTO VALLEY/NORTHEAST KY LATE IN THE  
OVERNIGHT PERIOD AS WELL. ADDITIONAL RAINFALL AMOUNTS THROUGH  
THE REMAINDER OF THE NEAR TERM PERIOD WILL BE ON THE ORDER OF A  
TENTH OR SO, WITH SLIGHTLY MORE POSSIBLE IN A FEW SPOTS. DRIER  
CONDITIONS WILL EVOLVE PAST 8 AM AREA-WIDE IN THE POST-FRONTAL  
ENVIRONMENT.  
 
LOW TEMPERATURES HAVE LIKELY BEEN REACHED ALREADY THIS EVENING  
AND WILL BEGIN TO PLATEAU AND INCH BACK UP LATE IN THE NIGHT AS  
SOUTHERLY SURFACE FLOW BECOMES ESTABLISHED AHEAD OF THE  
AFOREMENTIONED FRONT. FAIRLY UNIFORM TEMPS ARE EXPECTED  
OVERNIGHT IN THE UPPER 30S AND LOWER 40S, WHICH WILL TREND UP BY  
A FEW DEGREES BY DAYBREAK. COULD ALSO SEE SOME PATCHY FOG IN  
WEST-CENTRAL OHIO AND AREAS NORTH OF I-70 LATE IN THE NEAR TERM  
PERIOD AS WELL.  
 

 
   
SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/
 
 
WEAK HIGH PRESSURE WILL BUILD IN FROM THE SOUTHWEST SATURDAY  
AFTERNOON AS AN MID LEVEL TROUGH DIGS SOUTHEAST FROM THE  
CENTRAL ROCKIES INTO THE SOUTHERN PLAINS STATES. THIS WILL SHIFT  
UPPER LEVEL FLOW TO A MORE SOUTHWEST TO NORTHEAST ORIENTATION  
EAST OF THE TROUGH. ENERGY WILL EJECT THROUGH THE SOUTHWESTERLY  
FLOW INTO THE OHIO VALLEY SATURDAY NIGHT INTO SUNDAY, BRINGING  
MODERATE TO HEAVY RAINFALL. MODEL GUIDANCE STILL SHOWS  
SIGNIFICANT UNCERTAINTY AT THIS LATE STAGE, WITH THE GFS  
ENSEMBLE PAINTING HIGHEST CHANCES OF 2"+ RAINFALL VERY NEAR THE  
OHIO RIVER IN NORTHERN/NORTHEASTERN KENTUCKY, WHILE THE  
EUROPEAN ENSEMBLE POSITIONS IT TO THE SOUTH OF THE FORECAST  
AREA, THOUGH WITH HIGHER AMOUNTS. HIGH RESOLUTION MODELS SHOW  
POTENTIAL FOR TRAINING OF MODERATE TO HEAVY RAIN LATE SATURDAY  
NIGHT INTO SUNDAY MORNING IN NORTHEAST KENTUCKY.  
 
DESPITE THE UNCERTAINTY IN POSITION, THE POTENTIAL FOR 1.5" TO  
2.5" OF RAIN ON RELATIVELY SATURATED SOILS BRINGS SOME CAUSE FOR  
CONCERN WITH AREA STREAMS, ESPECIALLY SOUTH OF THE OHIO RIVER.  
PWATS RANGING FROM 1-1.5" DURING THIS TIME, SURFACE DEWPOINTS  
LIFTING INTO THE 50S, AND WARM CLOUD DEPTHS INCREASING TO NEAR  
10KFT DISPLAY THE STRONG POTENTIAL FOR EFFICIENT WARM RAIN  
PROCESSES. WILL CONTINUE TO TRACK THIS RAINFALL EVENT CLOSELY AS  
GUIDANCE ZEROES IN ON A MORE CONFIDENT TRACK.  
 

 
   
LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/
 
 
RAINFALL EVENT WILL BE ONGOING WITH PRIMARY FOCUS ACROSS SOUTHERN  
COUNTIES. THERE REMAINS UNCERTAINTY WHERE AXIS OF HEAVIEST RAINFALL  
WILL OCCUR WHICH OBVIOUSLY AFFECTS FLOOD POTENTIAL. EXPECT A FAIRLY  
SHARP NORTHERN GRADIENT TO HEAVIER RAIN AS WELL. GROUND IS SATURATED  
AND RAINFALL HAS THE POTENTIAL TO BE RATHER EFFICIENT. SO IN  
COLLABORATION WITH NEIGHBORING KENTUCKY OFFICES, HAVE GONE AHEAD AND  
ISSUED A FLOOD WATCH FOR A NUMBER OF NORTHERN KENTUCKY COUNTIES FROM  
LATE SATURDAY NIGHT THROUGH SUNDAY. THERE IS THE POSSIBILITY THAT  
THIS MAY NEED TO BE ADJUSTED NORTHWARDS A BIT, ESPECIALLY INTO SOUTH  
CENTRAL OHIO, IF MORE NORTHERN MODEL SOLUTIONS LOOK MORE LIKELY.  
 
RAIN INTENSITY IS FORECAST TO DIMINISH SUNDAY AFTERNOON, AND  
PRECIPITATION WILL COME TO AN END AFTER A COLD FRONT SWEEPS ACROSS  
THE AREA LATE SUNDAY AFTERNOON INTO THE EVENING. A SECONDARY  
BOUNDARY WILL PUSH THROUGH ON MONDAY WITH HIGH PRESSURE BUILDING  
ACROSS THE AREA MONDAY NIGHT AND MOVING EAST ON TUESDAY.  
 
THERE CONTINUES TO BE VARIATIONS IN THE GUIDANCE WHETHER A SYSTEM  
PASSES SOUTH OF THE AREA ON TUESDAY NIGHT INTO WEDNESDAY. WILL KEEP  
LOW CHANCE POPS FOR THIS TIME PERIOD. TEMPERATURES MAY GET COLD  
ENOUGH TUESDAY NIGHT FOR THERE TO BE RAIN OR SNOW. ANOTHER HIGH  
BUILDS IN THURSDAY. MID LEVEL FLOW WILL BE AMPLIFYING LATE IN THE  
WEEK WITH TROUGHING IN THE EAST. THIS COULD BRING ANOTHER WEAK  
SYSTEM THROUGH THE AREA FRIDAY.  
 

 
   
AVIATION /06Z SATURDAY THROUGH WEDNESDAY/
 
 
WEAK MID LEVEL SHORTWAVE AND ASSOCIATED ISENTROPIC LIFT WILL  
RESULT IN AN INCREASED CHANCE FOR SHOWERS OVERNIGHT. AS THE  
SHORTWAVE AND WEAK FORCING SHIFTS EAST -- EXPECT PCPN TO END  
FROM WEST TO EAST THRU 13Z. MVFR CEILINGS WHICH ARE DROPPING TO  
IFR ACROSS THE WESTERN TAF SITES WILL DO SO ACROSS ALL TAF  
SITES OVERNIGHT.  
 
THESE IFR CEILINGS WILL LINGER THROUGH THE MORNING HOURS BEFORE  
LIFTING TO MVFR BY EARLY AFTERNOON. AS WEAK SURFACE HIGH  
PRESSURE BUILDS ACROSS THE AREA THIS AFTN EXPECT TO SEE  
CONTINUED IMPROVEMENT. UNCERTAINTY EXISTS IF CLOUDS SCATTER OUT  
WITH VFR CONDITIONS DEVELOPING. HAVE KEPT MVFR CONDITIONS AT  
KCVG/KLUK WITH A PERIOD OF VFR CONDITIONS AT THE REMAINDER  
OF THE TAF SITES LATER IN THE DAY INTO THIS EVENING.  
 
MOISTURE INCREASES LATE THIS EVENING WITH CLOUDS AND RAIN  
SHOWERS OVERSPREADING THE AREA FROM THE SOUTHWEST BETWEEN 04Z  
AND 09Z. HAVE MVFR TO IFR CONDITIONS REDEVELOPING AT KCVG/KLUK  
WITH MVFR AT THE REMAINDER OF THE SITES LATE IN THE TAF PERIOD.  
 
OUTLOOK... MVFR/IFR CIGS AND MVFR VSBYS LIKELY LATE SATURDAY  
NIGHT INTO SUNDAY MORNING.  
 

 
   
ILN WATCHES/WARNINGS/ADVISORIES
 
 
OH...NONE.  
KY...FLOOD WATCH FROM LATE TONIGHT THROUGH SUNDAY EVENING FOR  
KYZ094>100.  
IN...NONE.  
 

 
 

 
SYNOPSIS...HOGUE  
NEAR TERM...KC  
SHORT TERM...HOGUE  
LONG TERM...  
AVIATION...AR  
 
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