Severe Thunderstorm Warning 148, NWS State College, PA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
215 PM EDT MON JUL 10 1995

RAMSDIS VSBL IMAGERY SHWG PLENTY OF CU DVLPMT IN WRN/NRN PA AND OH
ATTM. CU HVG A PREFERENCE FOR ALLEGHENNY FRNT WHICH IS TYPICAL. NO
MAJOR AREAS OF ORGANIZED CONVTN FORMING ATTM. ADAP INDICATING AMS
IS MARGINALLY UNSTBL NOW WITH LI/S FROM -4 TO -6. NGM/ETA INDICATE
THAT LOW-LVL MOISTURE CONV WILL INCREASE AND BECOME A MAXIMUM IN
CNTRL/ERN PA BY 00Z. THIS LOOKS GOOD FOR TWO REASONS: 1) TENDENCY
FOR LEE TROFFING TO OCCUR E OF MTNS IN WRLY FLO AND 2) LOW-LVL
BRANCH OF INDIRECT CIRCULATION FROM APPRCHG UPR LVL JET WILL LEAD
TO A SRLY AGEO ACCERELATION DVLPG A WK SRLY LLJ JET OVR ERN PA BY
00Z (SEEN BEST ON AVN GRIDDS AT 850 MB). THIS LLJ FEATURE WILL
FOCUS CONVERGE. IN ADDITION... LEFT EXIT REGION OF THIS UPR LVL JET
ASSCTD WITH SIGNIFICANT S/W WILL HELP TO STEEPEN LAPSE RATES ON TOP
OF WHAT SFC HEATING DOES LATE THIS AFTERNOON. WUD LIKE TO SEE
SOMETHING DVLPG ON RADAR BY NOW... BUT NOTHING AS OF PRESS TIME (
IPT REPORTS TCU). STILL THINK SCTRD RW/TRW WILL DVLP CNTRL/WRN MTNS
OF PA LATE THIS AFTERNOON AND MOV INTO SUS VLLY THIS EVENING. WILL
GO CHC POPS NRN/WRN CTP ZONES... AND HV LIKELY POPS SUS VLLY DUE TO
BETTER LO-LVL CNVGNCE TONIGHT.

AFTER THIS S/W PASSES E OF FA BY 12Z... ALL THREE MODELS SHOW ANTHR
WK VORT LOBE WORKING ACRS FA TUE. ETA DOESN/T SEEM TO CAPTURE THIS
NEXT FEATURE AS WELL AS NGM OR AVN WHICH BOTH HV SOME SFC
REFLECTION AND BETTER UPR LVL REFLECTION. AMS IS QUITE DRY BEHIND
FIRST S/W AND THIS SECOND S/W WILL BE FIGHTING UPR LVL CONV AND
DRYER AIR BEHIND TROF AXIS... SO UVV/S ARE NOT AS IMPRESSIVE. AVN
QPF SUGGESTS PRECIP ACRS FA AFTER 12Z TUE... NGM HAS MINUTE AMNTS
ALSO... BUT POPS BOTH MODELS ARE LO. SO WILL LEAVE OUT AND ALERT
NEXT SHIFT TO WATCH HOW THIS NEXT FEATURE EVOLVES NEXT MODEL RUN.
WILL GO PS ALL ZONES FOR NOW. SFC NW FLO TUE AND DOWNSLOPE WILL
LEAD TO VERY WARM TEMPS IN SUS VLLY... MDT MAY APPRCH 90.

FOR TUE NGT INTO WED... UPR LVL RDG BUILDS ACRS GREAT LAKES WITH
MAIN FOCUS IN THE FORM OF WAA AND LO-LVL CONV WELL W AND N OF
REGION. LOOKS TO BE DRY AND GRADUALLY WARMING INTO WED. WILL HV MO
CLR TUE NGT AND PC WED.

CTP ZONES IN A FEW. LOOKED AT PITWRKZFP/S AND THEY LOOK SIMILIAR TO
THE ONES I WILL SEND SOON. PHLSFDPHL ALSO LOOKS TO BE IN AGREEMENT
WITH MY THOUGHTS.

NICOSIA