285  
FXUS61 KRLX 190703  
AFDRLX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE CHARLESTON WV  
303 AM EDT FRI SEP 19 2014  
   
SYNOPSIS
 
 
MOISTURE INCREASES IN SOUTHEAST FLOW ALONG EASTERN SLOPES...AS HIGH  
PRESSURE DRIFTS EASTWARD THROUGH SATURDAY. COLD FRONT CROSSES LATE  
SUNDAY. HIGH PRESSURE DOMINATES NEXT WEEK.  
 

 
   
NEAR TERM /THROUGH TONIGHT/
 
 
HIGH PRESSURE WELL NNE OF THE AREA...OVER THE ST LAWRENCE RIVER  
VALLEY EARLY THIS MORNING...WILL DRIFT ESEWD...OFF THE NEW ENGLAND  
COAST THIS PERIOD. THIS WILL ALLOW LOW LEVEL FLOW TO TURN TO THE  
SE...RESULTING IN CLOUDS FORMING ALONG THE EASTERN SLOPES OF THE  
CENTRAL APPALACHIANS EARLY THIS MORNING.  
 
SE FLOW THERE...AND NE LOW LEVEL FLOW OVER THE MIDDLE OHIO  
VALLEY...WILL RESULT IN A SFC INVERTED TROUGH AXIS THAT DRIFTS WWD  
OUT OF THE MOUNTAINS THIS AFTERNOON. THUS HAVE ADJUSTED SCHC POPS  
TO REFLECT ISOLATED SHOWERS COMING WWD OUT OF THE MOUNTAINS LATE  
THIS AFTERNOON ALONG WITH ASSOCIATED INSTABILITY AXIS...BEFORE  
WINDING DOWN TONIGHT. WEAK FORCING...AND A CAP AROUND 10 KFT SHOULD  
KEEP CONVECTION FROM GETTING TALL ENOUGH FOR CHARGE SEPARATION  
SUFFICIENT FOR LIGHTNING.  
 
THE SFC TROUGH WILL DISSIPATE THIS EVENING AS THE HIGH MOVES FARTHER  
AWAY...AND LOW LEVEL FLOW BECOMES S TO SE THROUGHOUT THE AREA  
TONIGHT. THE LOW CLOUDS ALONG THE EASTERN SLOPES MAY BREAK UP FOR A  
TIME THIS EVENING...BEFORE REFORMING OVERNIGHT.  
 
TEMPERATURES LOOKED GOOD IN TERMS OF LATEST GUIDANCE...INCLUDING THE  
COOLING AFFECT OF THE SE FLOW ON THE EASTERN SLOPES TODAY AND  
TONIGHT.  
 

 
   
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/
 
 
HIGH PRESSURE OFF TO THE NORTHEAST AT THE BEGINNING OF THE  
PERIOD...WITH A WARM...MOIST SOUTHERLY FLOW TAKING HOLD ACROSS THE  
REGION. WARM FRONTAL BOUNDARY ASSOCIATED WITH LOW PRESSURE THAT WILL  
SKIRT ACROSS THE GREAT LAKES AREA...WILL LIFT NORTH ACROSS THE AREA  
ON SATURDAY. COULD BE A FEW LIGHT SHOWERS ON SATURDAY OUT AHEAD OF  
THE APPROACHING COLD FRONT...BUT AT THIS POINT...MOISTURE APPEARS  
LIMITED...SO WILL MAINTAIN A DRY FORECAST.  
 
COLD FRONT WILL ENTER SOUTHEAST OHIO EARLY SUNDAY...PUSHING OFF TO  
THE EAST SUNDAY EVENING. NAM CONTINUES TO BE THE SLOWER OF THE  
MODELS WITH PROGRESSING THIS FRONT EAST...AND TENDED TO FOLLOW  
GFS/ECMWF SOLUTIONS A LITTLE CLOSER. EXPECTING SHOWERS AND  
THUNDERSTORMS ON SUNDAY AS THE FRONT PUSHES EAST OF THE AREA...WITH  
A FEW LIGHT SHOWERS LINGERING INTO MONDAY AS UPPER TROUGH PUSHES  
THROUGH. DID ELECT TO HOLD ONTO A SLIGHT CHANCE SUNDAY NIGHT AND  
EARLY MONDAY AS A RESULT.  
 
DRIER AIR EXPECTED TO RETURN TO THE AREA EARLY NEXT WEEK AS HIGH  
PRESSURE...AND NORTHWESTERLY FLOW ALOFT TAKES HOLD. DROPPED DEW  
POINTS EARLY NEXT WEEK TO ACCOUNT FOR THIS.  
 

 
   
LONG TERM /MONDAY THROUGH THURSDAY/
 
 
USED WPC THINKING WITH SOME MINOR TWEAKS. COLD FRONT WILL PUSH  
SOUTHEAST OF THE MOUNTAINS SUNDAY NIGHT WITH HIGH PRESSURE TAKING  
CONTROL BY MONDAY AFTERNOON. THE HIGH SHOULD BE IN CONTROL THROUGH  
THE REMAINDER OF THE PERIOD...RESULTING IN DRY AND SEASONABLY COOL  
TEMPERATURES.  
 
WPC TEMPS LOOKED GOOD AND WERE GENERALLY USED.  
 

 
   
AVIATION /07Z FRIDAY THROUGH TUESDAY/
 
 
HIGH PRESSURE SLOWLY DRIFTS AWAY TO THE NE THRU FRI BEFORE SLIDING  
OFF THE E COAST THIS WEEKEND. IN THE NEAR TERM...THIS ALLOWS LOW  
LEVEL FLOW TO VEER TO THE SE OVERNIGHT...BY ABOUT 09Z FRI. THIS  
WILL ALLOW LOW CLOUDS TO INCREASE ALONG THE EASTERN SLOPES...WITH  
MVFR CIGS 1 TO 2 KFT AT BKW FRI STARTING AROUND 09Z AND THEN  
SCATTERING OUT FOR A TIME FRI EVENING.  
 
DENSE VALLEY FOG IS LIKELY TO FORM ELSEWHERE...FIRST OVER THE TUG  
FORK AND COAL FIELDS WHERE DEW POINTS ARE HIGHEST...AND LASTLY ALONG  
RIVERS FARTHER N. MORNING CU IS LIKELY AS THE FOG DISSIPATES AFTER  
SUNRISE...LEADING TO PATCHY MVFR CIGS 14-18Z FRI. VFR WILL FOLLOW  
WITH AFTERNOON CUR AOA 4 KFT.  
 
AFTER A CALM OVERNIGHT...SFC FLOW WILL BECOME LIGHT SE OVER THE  
CENTRAL APPALACHIANS FRI AND LIGHT NE BECOMING LIGHT SE OVER THE  
MIDDLE OHIO VALLEY. LIGHT TO MODERATE NE FLOW ALOFT WILL BECOME  
LIGHT SE OVER THE CENTRAL APPALACHIANS LATE OVERNIGHT AND OVER THE  
MIDDLE OHIO VALLEY DURING THE DAY FRI.  
 
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z SATURDAY...  
 
FORECAST CONFIDENCE: MEDIUM.  
 
ALTERNATE SCENARIOS: TIMING LOWERING CEILING INTO SRN WV MOUNTAINS  
WITH THE DEVELOPING EASTERLY UPSLOPE FLOW AROUND BKW MAY VARY.  
TIMING AND DENSITY OF FOG MAY ALSO VARY INTO FRI MORNING.  
 
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY  
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:  
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.  
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.  
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.  
 
DATE FRI 09/19/14  
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17  
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13  
CRW CONSISTENCY M M L L L L L L M M M H  
HTS CONSISTENCY H H H L L L L H H H H H  
BKW CONSISTENCY H H H M M M M M M M M M  
EKN CONSISTENCY H H H L L L L L M H M M  
PKB CONSISTENCY H H H H H H H H H H H H  
CKB CONSISTENCY H H H H H H H H H H H H  
 
AFTER 06Z SATURDAY...  
BRIEF IFR CONDITIONS POSSIBLE SUNDAY IN SHOWERS/STORMS.  
 

 
   
RLX WATCHES/WARNINGS/ADVISORIES
 
 
WV...NONE.  
OH...NONE.  
KY...NONE.  
VA...NONE.  
 

 
 

 
SYNOPSIS...TRM/SL  
NEAR TERM...TRM  
SHORT TERM...SL  
LONG TERM...JSH  
AVIATION...TRM  
 
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