Severe Thunderstorm Warning 8, NWS State College, PA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1135 AM EDT THU MAY 3 2012

.SYNOPSIS...
AN OSCILLATING FRONTAL BOUNDARY WILL REMAIN OVER EASTERN PA
TODAY...THEN LIFT NORTH OF THE ENTIRE STATE ON FRIDAY. A COLD
FRONT WILL PUSH SOUTH ACROSS THE REGION FRIDAY NIGHT. A DEEPENING
UPPER TROUGH WILL APPROACH THE AREA EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
MCV NOW PUSHING THROUGH LOWER SUSQ TAKING LAST VESTIGES OF LAST
NIGHT'S CONVECTION (NOW JUST A FEW SPRINKLES) WITH IT. LATEST
VISIBLE LOOP SHOWS STATIONARY FRONT WHICH WAS DRAPED OVER CENTRAL
PA BISECTING WEST FROM EAST EARLIER THIS MORNING NOW MAKING GOOD
EASTWARD PROGRESS BEHIND THE DEPARTING MCV. LOW CLOUDS AND FOG
ACROSS NORTHERN TIER DISSIPATING QUICKLY ADN TEMPS WARMING INTO
THE LOWER TO MIDDLE 70S.

MORNING MODELS SIMILAR TO PREVIOUS THINKING...DEPICTING A MOIST
INSTABILITY AXIS BUILDING OVER WESTERN AND CENTRAL PA THIS
AFTERNOON CAPABLE OF SUPPORTING SCATTERED DEEP CONVECTION. LOW
SHEAR UNDER THE SPRAWLING UPPER RIDGE AND HIGH PRECIPITABLE WATER
MEAN THAT PULSE CELLS WILL BE THE FAVORED MODE WITH LOCALLY HEAVY
RAIN THE MAIN THREAT DUE TO ANY SLOWER MOVING CELLS. LATEST HRR-
3KM AND COSPA DATA INDICATE CONVECTIVE INITIATION OVER THE HIGH
TERRAIN OF WESTERN AND CENTRAL PA WEST OF THE ADVANCING WARM
FRONTAL BOUNDARY AFT 19Z. DESPITE DIURNAL DESTABILIZATION THIS
AFTN...THE OVERALL LACK OF FORCING AND FOCUS SHOULD KEEP
CONVECTIVE CVRG ISOLD TO SCT...KEPT POPS AOB 50 PCT.

MAXES WILL BE VERY WARM AND QUITE MUGGY FOR EARLY MAY WITH HIGHS
AROUND 80F AND SFC DEWPOINTS IN THE 60S. MAX TEMPS WILL AVG 10-15F
ABV NORMAL WHEN COMPARED TO 30YR CLIMO RECORDS...BUT STILL ABOUT
10F SHY OF RECORD LEVELS FOR THE DATE.

LOWER CONFIDENCE FCST HEADING INTO THE TNT PD. IT APPEARS THE PRIMARY
PCPN AXIS SHOULD BE LOCATED TO THE NW OF CENTRAL PA /FM THE IA
CORNBELT EWD THRU THE LWR GRT LKS/ AS A SERIES OF MID-LVL IMPULSES
INTERACT WITH FAVORABLE UPPER JET DYNAMICS...LOW-MID LVL ISENT LIFT
VIA SWLY LLJ AND POOL OF HI PWATS ALONG AND AHEAD OF SLOW-MOVG FNTL
BNDRY. WILL CARRY MEDIUM TO LOW CHC POPS BASED ON MDL CONSENSUS
BLEND. OVERNIGHT READINGS WILL BE VERY MILD IN THE UPPER 50S AND LOW
60S.

&&

.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
FAST-MOVING SHORTWAVE TRACKING ACROSS S ONTARIO/QUEBEC WILL PUSH A
COLD FRONT THRU CENTRAL PA FRI EVENING. AM SUNSHINE SOUTH OF FRONT
SHOULD PUSH READINGS INTO THE L/80S ACROSS MUCH OF CENTRAL PA BY
EARLY AFTN...RESULTING IN A MODERATELY UNSTABLE AIR MASS /SREF
MEAN CAPES ARND 1000 J/KG/. GIVEN ONLY MODEST DEEP LYR
SHEAR...DON/T EXPECT ORGANIZED...WIDESPREAD SVR WX. BEST CHC OF
ISOLATED SVR WX APPEARS TO BE ACROSS NORTHEAST PA...WHERE 00Z MDL
DATA AGREES THE HIGHEST CAPES WILL DEVELOP BY LATE AFTN. DWINDLING
LINE OF CONVECTION SHOULD SHIFT SOUTH ACROSS THE STATE FRI EVENING
WITH PASSAGE OF COLD FRONT.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
A DRY...COOLER WX PATTERN APPEARS LIKELY FOR THE UPCOMING
WEEKEND...AS LG SFC ANTICYCLONE BUILDS SE FROM CANADA. PASSAGE OF
A WEAK...FAST-MOVING SHORTWAVE COULD PRODUCE A FEW PM SHRA/TSRA ACROSS
SOUTHERN PA ON SAT. HOWEVER...CONFIDENCE LOW ATTM AND WILL KEEP
POPS LOW. GEFS 850 TEMPS STILL 10-12C SAT...SUPPORTIVE OF HIGHS IN
THE 70S TO NR 80F SE. SUNDAY SHOULD BE DRY AND SEASONABLE AS SFC RIDGE
BUILDS DIRECTLY OVR THE STATE.

THERE IS A BROAD MDL CONSENSUS FOR OUR NEXT ORGANIZED PCPN EVENT
NEXT TUE-WED...AS A MID-UPPER TROUGH SHIFTS EWD FM THE UPPER
MIDWEST AND CENTRAL PLAINS STATES. THERE IS SOME DISCREPANCY
BETWEEN THE MODELS ON THE TIMING AND PROGRESSION OF THAT
SYSTEM...THOUGH BOTH GEFS AND ECMWF ENSEMBLE MEAN SOLUTIONS TRACK
SFC COLD FRONT THRU THE AREA EITHER TUES OR EARLY WED.

UNSETTLED...COOL WX APPEARS LIKELY LATE NEXT WEEK...AS UPPER TROF
SLOWLY PASSES THRU.

&&

.AVIATION /14Z THURSDAY THROUGH MONDAY/...
EXPECT LOW CLOUDS/FOG AND ASSOCD MVFR-IFR CONDS TO IMPROVE TO VFR
THRU THE LATE MORNING AND INTO THE AFTN. JST/AOO VCNTY WILL BE
IMPACTED BY -SHRA/-TSRA THRU 13-14Z.

HI RES MDL DATA/COSPA DEVELOPS TSTMS OVR NW PA BY 18Z AND ADDED
VCTS TO FM GROUP. DECIDED NOT MENTION TS FOR THIS AFTN AT
REMAINING TERMINALS GIVEN LOW CONFIDENCE/COVERAGE. THE HIGHEST
PROBABILITY FOR SHRA/TSRA TONIGHT IS OVR NRN SXNS. TABULAR DATA IS
FAVORS THE RETURN OF LOW CIGS AND FOG LATE TONIGHT INTO EARLY FRI
IN THE SE AIRFIELDS AND HAVE ADDED MVFR/IFR GROUPS AT MDT AND LNS
AFT 03Z.

OUTLOOK...
FRI...SCT PM TSRA IMPACTS.
SAT...ISOLD TSRA IMPACTS PSBL OVER SRN AIRFIELDS.
SUN-MON...VFR.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

SYNOPSIS...FITZGERALD
NEAR TERM...DEVOIR/STEINBUGL
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/STEINBUGL
AVIATION...STEINBUGL

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE STATE COLLEGE PA
215 AM EDT THU MAY 3 2012

PAZ006-012-018-019-026>028-035>037-041-042-045-046-049>053-056>059-
063>066-040615-
POTTER-NORTHERN CLINTON-NORTHERN CENTRE-SOUTHERN CENTRE-HUNTINGDON-
MIFFLIN-JUNIATA-FULTON-FRANKLIN-TIOGA-NORTHERN LYCOMING-SULLIVAN-
SOUTHERN CLINTON-SOUTHERN LYCOMING-UNION-SNYDER-MONTOUR-
NORTHUMBERLAND-COLUMBIA-PERRY-DAUPHIN-SCHUYLKILL-LEBANON-CUMBERLAND-
ADAMS-YORK-LANCASTER-
215 AM EDT THU MAY 3 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA.

.DAY ONE...TODAY AND TONIGHT.

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

AN APPROACHING COLD FRONT WILL PRODUCE LATE DAY THUNDERSTORMS
ACROSS THE AREA ON FRIDAY. THERE IS A SLIGHT CHANCE THAT SOME OF
THESE STORMS COULD PRODUCE DAMAGING WIND GUSTS OR LARGE HAIL.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

PAZ004-005-010-011-017-024-025-033-034-040615-
WARREN-MCKEAN-ELK-CAMERON-CLEARFIELD-CAMBRIA-BLAIR-SOMERSET-BEDFORD-
215 AM EDT THU MAY 3 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA.

.DAY ONE...TODAY AND TONIGHT.

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
143 PM EDT THU MAY 3 2012

PAZ004-031830-
WARREN PA-
143 PM EDT THU MAY 3 2012

...A STRONG THUNDERSTORM WILL AFFECT NORTHWESTERN WARREN COUNTY...

AT 136 PM EDT...A STRONG THUNDERSTORM WAS 12 MILES WEST OF ELGIN...
MOVING EAST AT 20 MPH.

WIND GUSTS TO 30 MPH AND PEA SIZE HAIL ARE POSSIBLE WITH THIS STORM.
THIS STORM WILL AFFECT COLUMBUS.

THIS WILL IMPACT ROUTE 6.

LAT...LON 4178 7948 4181 7962 4197 7962 4200 7961
      4200 7943

FORECASTER: DEVOIR