484  
FXUS61 KPBZ 191915  
AFDPBZ  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PITTSBURGH PA  
215 PM EST TUE NOV 19 2019  
   
SYNOPSIS
 
 
BROAD UPPER-LEVEL TROUGHING WILL MAINTAIN COOLER TEMPERATURE  
ALONG WITH PATCHY DRIZZLE TODAY. DRIZZLE OR FREEZING DRIZZLE MAY BE  
POSSIBLE LATE TONIGHT BEFORE WARMER TEMPERATURE RETURNS DURING THE  
SECOND HALF OF THE WEEK. THE HIGHEST CHANCE FOR PRECIPITATION WILL  
COME LATE THURSDAY AND FRIDAY.  
 

 
   
NEAR TERM /THROUGH TONIGHT/
 
 
LOW-LEVEL MOISTURE HAS BEEN MAINTAINED THROUGH MUCH OF THE DAY  
BENEATH A STOUT INVERSION NEAR H8, HELPING CLOUD COVER TO PERSEVERE.  
AS A RESULT, HEATING/MIXING HAVE BEEN LIMITED, AND A NEAR-SATURATED  
LOW-LEVEL THERMAL PROFILE HAS REMAINED.  
 
A SHORTWAVE TROUGH CROSSING THIS AFTERNOON AND EVENING WILL SUPPORT  
MODEST LIFT OF THIS SATURATED LAYER, ENSURING CONTINUOUS OVERCAST AND  
PATCHY DRIZZLE/SPRINKLES THIS AFTERNOON AND EVENING.  
 
IN THE WAKE OF THE WAVE, WEAK NWLY FLOW ACROSS LAKE ERIE WILL PROVIDE  
OROGRAPHIC LIFT TO THIS SATURATED AIRMASS. BUT A LACK OF ICE CRYSTALS  
SUGGESTS ANY PRECIPITATION IS MOST LIKELY TO BE DRIZZLE/FREEZING  
DRIZZLE, ESPECIALLY IN NRN ZONES AND THE RIDGE ZONES, WHERE SFC COLD  
AIR MAY BE SUFFICIENT FOR MODEST ICE DEVELOPMENT.  
 
AT THIS TIME, LOW CONFIDENCE AND COMPLICATING FACTORS LIKE WARM  
GROUND AND PATCHY COVERAGE PRECLUDE ANY HEADLINES, BUT THIS CONCERN  
WILL NEED TO BE MONITORED THIS EVENING. THE CONCERN WILL BE INCLUDED  
IN THE HWO.  
 

 
   
SHORT TERM /WEDNESDAY THROUGH THURSDAY/
 
 
DRY CONDITIONS AND A WARMING TREND ARE EXPECTED WED AND THU AS  
RIDGING BUILDS SFC HIGH PRESSURE ACROSS THE REGION, WITH FORECAST  
MAXIMA ON THU REACHING SLIGHTLY ABOVE SEASONAL AVERAGE.  
 
RAIN ONSET HAS TRENDED SLOWER THE LAST FEW DAYS, WITH MINIMAL MORNING  
CHANCES AND PROBABILITY INCREASING ONLY SLIGHTLY LATE THU AFTERNOON.  
 

 
   
LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/
 
 
PRECIPITATION CHANCES WILL INCREASE MARKEDLY LATE THU NIGHT IN  
ADVANCE OF A COLD FRONT, WHICH IS EXPECTED TO BRING MORE WIDESPREAD  
PRECIPITATION TO THE REGION. BEST CHANCES AT THIS TIME LOOK TO BE  
LATE THU NIGHT-FRI MORNING, ALTHOUGH FORECASTED AMOUNTS APPEAR TO BE  
LIGHT.  
 
TEMPERATURE THU AND THU NIGHT WILL BE COMPARATIVELY MILD AS CLOUD  
COVER AND WARM ADVECTION ON SWLY FLOW WILL LIMIT TYPICAL DIURNAL  
TRENDS. MODELS ARE IN FAIRLY GOOD AGREEMENT WITH FRONTAL PASSAGE  
DURING THE DAY ON FRI, WITH A RETURN TO BELOW-AVERAGE TEMPERATURE.  
 
ALTHOUGH MEDIUM-RANGE DETAILS VARY AMONG ENSEMBLES/MEMBERS, THE  
GENERAL IDEA OF BROAD ERN-CONUS TROUGHING INTO EARLY NEXT WEEK  
APPEARS CONSISTENT UNTIL RIDGING BUILDS MID-WEEK. BELOW-AVERAGE  
TEMPERATURE IS EXPECTED THROUGH TUE, WITH A POTENTIAL WARM-UP ON  
WED.  
 

 
   
AVIATION /19Z TUESDAY THROUGH SUNDAY/
 
 
LOW-LEVEL MOISTURE UNDER AN UPPER-LEVEL TROUGH SHOULD MAINTAIN MVFR  
CONDITIONS INTO WEDNESDAY. WITH LIGHT WIND AND OVERNIGHT LOWS  
FALLING TOWARDS THE CROSSOVER TEMPERATURE, FOG SHOULD FORM AT  
FKL/DUJ.  
 
WINDS ARE EXPECTED TO SHIFT FROM THE NORTHWEST EARLY WEDNESDAY AS  
THE UPPER-LEVEL TROUGH EXITS EAST. COLD ADVECTION OVER LAKE ERIE  
WILL REINFORCE MVFR STRATOCU COVERAGE FOR AREAS NORTHEAST OF HLG  
INTO THE LATE EVENING; THERE MAY BE BRIEF PERIODS OF IFR FOR FKL/DUJ.  
FKL ALSO COULD OBSERVE FREEZING DRIZZLE OR A RAIN/SNOW MIX FOR A  
BRIEF PERIOD OF TIME NEAR 12Z, HOWEVER CONFIDENCE IS NOT HIGH ENOUGH  
TO MENTION IN THE TAF. BUILDING HIGH PRESSURE IN CENTRAL OHIO SHOULD  
ELIMINATE RESTRICTIONS FROM WEST TO EAST LATE WEDNESDAY/EARLY  
THURSDAY MORNING.  
   
OUTLOOK
 
 
MORE WIDESPREAD RESTRICTIONS ARE EXPECTED WITH A LATE-WEEK FRONTAL  
ENCROACHMENT.  
 

 
   
PBZ WATCHES/WARNINGS/ADVISORIES
 
 
MD...NONE.  
OH...NONE.  
PA...NONE.  
WV...NONE.  
 

 
 

 
 
KRAMAR  
 
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