343 
FXUS61 KPBZ 031923
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
320 PM EDT MON JUN 3 2002

OPERATIONAL MRF MORE IN LINE WITH THE MAIN CLUSTER OF MRF ENSEMBLES 
TODAY. ALL SHOW THE UPPER LEVEL FLOW PATTERN EVOLVING FROM A SPLIT 
FLOW OUT WEST INTO A PROGRESSIVE TROUGH DEVELOPING OVER THE ROCKIES 
LATE THIS WEEK WITH A SUBSEQUENT UPPER LEVEL RIDGE IN THE EAST. 
DURING EARLY NEXT WEEK...THE EASTBOUND ROCKIES TROUGH WILL PASS 
THROUGH THE HEAD OF THE OHIO REGION. 

SO...IN THE SHORT TERM...THE ETA SHOWS THE FIRST OF SEVERAL IMPULSES 
BEING EJECTED FROM THE ROCKIES SPLIT FLOW TROUGH WILL BE CROSSING 
THE HEAD OF THE OHIO REGION TONIGHT...WITH THE HUMID WARM FRONT 
STILL OVER KENTUCKY AND SOUTHERN WEST VIRGINIA. AS THE WARM FRONT 
BEGINS TO MOVE NORTHWARD...ANOTHER WILL CROSS THE REGION TUESDAY 
MORNING WITH THE WARM FRONTAL PASSAGE...AND A THIRD IMPULSE WILL 
CROSS THE REGION LATE TUESDAY...IMMERSED IN WARM SECTOR HIGH 
HUMIDITY. 

USING MODEL SOUNDINGS WITH INPUT FROM HPC AND SPC DISCUSSIONS... 
OPTED TO DROP MENTION OF HEAVY RAIN TONIGHT/DEEP MOISTURE TOO FAR TO 
THE SOUTH/...AND MAY ADD MENTION OF GUSTY WINDS TO THUNDERSTORMS 
LATE TUESDAY PER LARGE CAPE/1500-2000J/ AND MODERATE 
HELICITY/50-200M2S-2/.  THUNDERSTORMS WILL HAVE SIMILAR POTENTIAL 
LATE WEDNESDAY AS THE AVN SHOWS THE FRONT RETURNS AS A COLD FRONT 
MOVING SOUTH. 

THIS WILL BE FOLLOWED BY A DRY PERIOD FROM MIDDAY THURSDAY INTO 
EARLY MONDAY. AS THE PROGRESSIVE TROUGH APPROACHES...A PREFRONTAL 
BAND OF THUNDERSTORMS CAN DEVELOP OVER THE UPPER OHIO VALLEY. 

FOR TEMPERATURES...USED AVN MOS ADJUSTED MAINLY BY ETA MOS FOR DAYS 
1-3...THEN MAINLY MRF ENSEMBLE MEAN MOS FOR DAYS 4-7. ...GIORDANO


.PBZ...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.