Severe Thunderstorm Warning 184, NWS State College, PA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
259 PM EDT FRI JUL 29 2011

.SYNOPSIS...

A FRONTAL SYSTEM WILL MOVE THROUGH THE REGION TONIGHT. SHOWERS AND
THUNDERSTORMS WILL DEVELOP AHEAD OF THE FRONT THIS AFTERNOON. A
FEW OF THESE STORMS WILL BRING HEAVY RAINFALL AND STRONG WINDS
THIS AFTERNOON AND EVENING. STORMS WILL WIND DOWN OVERNIGHT AS THE
FRONT SAGS SOUTH OF THE AREA. BEHIND THIS FRONT WILL BE DRIER AIR
FOR THE WEEKEND...THOUGH AFTERNOON TEMPERATURES WILL STILL RUN
ABOVE AVERAGE...MAKING FOR ANOTHER HOT SUMMER AFTERNOON BOTH DAYS.

&&

.NEAR TERM /UNTIL 8 PM THIS EVENING/...

UPDATED THE NEAR TERM FOR THE SEVERE THUNDERSTORM WATCH...

CONVECTION BEGINNING TO INCREASE OVER THE CWA. LOOKS LIKE THERE IS
A BROKEN LINE OF CONVECTION FORMING WEST TO EAST FROM CENTRAL OHIO
THROUGH CENTRAL PA TURNING NE INTO UPSTATE NY. HRRR RUNS SHOW THIS
AREA AS THE FOCUS FOR STORMS FOR THE REST OF THE DAY. WITH SPEED
SHEAR IN PLACE SOME OF THESE STORMS WILL HAVE STRONG OUTFLOW
BOUNDARIES WITH THEM AS THEY MOVE EAST AND SOUTHEAST.

HEAT ADVY AND AIR QUALITY ALERT REMAIN IN EFFECT FOR THE LWR SUSQ
VLY WITH HEAT INDEX VALUES BTWN 100-104F AND CODE ORANGE AIR
QUALITY LEVELS. HIGHS WILL RANGE FROM THE LOW 80S IN THE NW MTNS
TO NEAR 100 OVR SOUTH MTN.

&&

.SHORT TERM /8 PM THIS EVENING THROUGH 6 PM SATURDAY/...
THE COLD FRONT WILL SHIFT SWD ACRS SRN PENN OVRNGT WITH IMPROVING
CONDS FROM NORTH TO SOUTH. MUCH DRIER...BELOW NORMAL PW AIR WILL
BE FOUND IN THE NORTH BY DAYBREAK SATURDAY AS SFC RIDGE SLIDES EWD
FM THE OH VLY. THE BEST CHC FOR LINGERING RAINS WILL BE ALONG THE
SRN TIER CNTYS. MDL DATA SUGGESTS SOME SHOWERS COULD LINGER OVER
SW PA AFT MIDNIGHT NEAR AREA OF HIER PWS. DEWPOINTS DROP
SIGNIFICANTLY SATURDAY...WITH A WARM AFTERNOON BUT MUCH LOWER HEAT INDICES.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...

SUNDAY LOOKS DRY AND WARM AS A WEAK SURFACE HIGH SLIDES OVER THE
AREA.

SYNOPTIC FLOW WILL BE BROAD NORTHWESTERLY AROUND A BIG RIDGE
OVER THE CENTRAL US AND UPPER LOW OVER ERN CANADA NEAR HUDSON'S
BAY. THIS WILL AFFORD SOME OPPORTUNITIES FOR PRECIP AS WEAK
DISTURBANCES ROTATE DOWN INTO THE NERN US AROUND THE PERIPHERY OF
THE RIDGE.

FIRST OPPORTUNITY IN THE EXTENDED SEEMS LIKE IT WILL BE MONDAY AS
GUIDANCE AGREES IN MAKING A COLD FRONT APPROACH THE AREA. CURRENT
TIMING SUGGESTS WE SEE HIGH PRESSURE BUILD IN FOR TUES INTO MID
WEEK BEFORE ANOTHER DISTURBANCE BRINGS PRECIP SOMETIME WED INTO
THURS.

IT LOOKS LIKE ANOTHER VERY WARM PERIOD COMING WITH TEMPERATURES
AVERAGING SOME 5 TO 10 DEG ABOVE NORMAL INTO THE END OF THE WEEK.

&&

.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
FRONT WILL TRAVERSE THE REGION THIS AFTN AND PRODUCE SCT- BKN
LINES OF TSTMS WITH PDS OF LCL MVFR/IFR CONDS. SOME STORMS MAY BE
STRONG TO SEVERE. WESTERLY WINDS MAY GUST UP TO 20 KTS THIS AFTN
OVR THE ALLEGHENIES.

FOLLOWING THE PASSAGE OF THE FRONT LATE TNT HIGH PRESSURE WILL
BUILD OVER THE COMMONWEALTH FROM THE OHIO VALLEY. ASIDE FROM SOME
MORNING FOG...EXPECT PREVAILING VFR CONDITIONS THROUGHOUT THE
WEEKEND. A SECONDARY COLD FRONT WILL SLIDE IN FROM THE NORTH/WEST
ON MONDAY...BRINGING A CHANCE OF ISOLATED SHRA/TSRA. HIGH PRESSURE
WILL BUILD INTO THE REGION AGAIN ON TUESDAY.

OUTLOOK...
SAT-SUN...VFR WITH A.M. FOG.
MON...MAINLY VFR WITH BRIEF MVFR POSSIBLE IN SHRA/TSRA.
TUE...VFR. NO SIG WX.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR PAZ036-056-057-
059-063>066.

&&

SYNOPSIS...ROSS/LA CORTE/STEINBUGL
NEAR TERM...ROSS/STEINBUGL
SHORT TERM...ROSS/STEINBUGL
LONG TERM...LA CORTE/MARTIN
AVIATION...STEINBUGL/COLBERT

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE STATE COLLEGE PA
245 PM EDT FRI JUL 29 2011

PAZ012-017>019-024>028-033>035-037-041-042-045-046-049>053-058-
301845-
NORTHERN CLINTON-CLEARFIELD-NORTHERN CENTRE-SOUTHERN CENTRE-CAMBRIA-
BLAIR-HUNTINGDON-MIFFLIN-JUNIATA-SOMERSET-BEDFORD-FULTON-TIOGA-
NORTHERN LYCOMING-SULLIVAN-SOUTHERN CLINTON-SOUTHERN LYCOMING-UNION-
SNYDER-MONTOUR-NORTHUMBERLAND-COLUMBIA-SCHUYLKILL-
245 PM EDT FRI JUL 29 2011

...SEVERE THUNDERSTORM WATCH 699 IN EFFECT UNTIL 11 PM EDT THIS
EVENING...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO
WEATHER.GOV/STATECOLLEGE ON THE INTERNET FOR MORE
INFORMATION ABOUT THE FOLLOWING HAZARDS.

   SEVERE THUNDERSTORM WATCH.

A COLD FRONT NORTH OF THE LOWER GREAT LAKES EARLY THIS
MORNING WILL MOVE SOUTHWARD ACROSS THE KEYSTONE STATE
LATE TODAY.

STRONG TO SEVERE STORMS WILL BE POSSIBLE ACROSS THE REGION
INTO THE EARLY EVENING HOURS. SOME STORMS MAY BE SEVERE...WITH
TORRENTIAL RAIN...DAMAGING WINDS...AND PERHAPS HAIL. RAPID CHANGES
IN CONDITIONS WILL BE LIKELY. THE THREAT OF SEVERE WEATHER SHOULD
END FROM NORTH TO SOUTH BY MID TO LATE EVENING.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

PAZ036-056-057-059-063>066-301845-
FRANKLIN-PERRY-DAUPHIN-LEBANON-CUMBERLAND-ADAMS-YORK-LANCASTER-
245 PM EDT FRI JUL 29 2011

...HEAT ADVISORY IN EFFECT UNTIL 8 PM EDT THIS EVENING...
...SEVERE THUNDERSTORM WATCH 699 IN EFFECT UNTIL 11 PM EDT THIS
EVENING...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO
WEATHER.GOV/STATECOLLEGE ON THE INTERNET FOR MORE
INFORMATION ABOUT THE FOLLOWING HAZARDS.

   HEAT ADVISORY.
   SEVERE THUNDERSTORM WATCH.

STRONG TO SEVERE STORMS WILL BE POSSIBLE ACROSS THE LOWER
SUSQUEHANNA VALLEY THIS AFTERNOON INTO THE MID EVENING HOURS.
SOME STORMS MAY BE SEVERE...WITH TORRENTIAL RAIN...DAMAGING WINDS...
AND PERHAPS HAIL. RAPID CHANGES IN CONDITIONS WILL BE LIKELY. THE
THREAT OF SEVERE WEATHER SHOULD END FROM NORTH TO SOUTH BY MID TO
LATE EVENING.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

PAZ004>006-010-011-301845-
WARREN-MCKEAN-POTTER-ELK-CAMERON-
245 PM EDT FRI JUL 29 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

A COLD FRONT WILL MOVE SOUTHWARD ACROSS THE KEYSTONE STATE LATE
TODAY.

STRONG TO SEVERE STORMS WILL BE POSSIBLE ACROSS THE REGION
FROM LATE MORNING INTO THE EARLY EVENING HOURS. SOME STORMS
MAY BE SEVERE...WITH TORRENTIAL RAIN...DAMAGING WINDS...AND
PERHAPS HAIL. RAPID CHANGES IN CONDITIONS WILL BE LIKELY. THE
THREAT OF SEVERE WEATHER SHOULD END FROM NORTH TO SOUTH BY MID
TO LATE EVENING.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
352 PM EDT FRI JUL 29 2011

PAZ024>026-292015-
BLAIR PA-CAMBRIA PA-HUNTINGDON PA-
352 PM EDT FRI JUL 29 2011

...STRONG THUNDERSTORMS WILL AFFECT BLAIR...CENTRAL CAMBRIA AND
NORTHERN HUNTINGDON COUNTIES...

AN AREA OF STRONG THUNDERSTORMS COVERED PORTIONS OF BLAIR...CAMBRIA
AND HUNTINGDON COUNTIES AT 348 PM EDT. THE STRONG THUNDERSTORMS WERE
GENERALLY MOVING EAST AT 35 MPH.

FREQUENT LIGHTNING AND WIND GUSTS TO 30 MPH ARE POSSIBLE WITH THESE
STRONG THUNDERSTORMS. VERY HEAVY RAIN WILL FALL FROM THESE STRONG
THUNDERSTORMS...AND WILL CAUSE WATER TO POND ON ROADS AND FILL POOR
DRAINAGE AREAS. THE RAIN WILL CAUSE RAPID RISES ON SMALL STREAMS AND
CREEKS.

THIS WILL IMPACT I-99 BETWEEN MILE MARKERS 23 AND 51.

THIS WILL ALSO IMPACT THE FOLLOWING MAJOR ROADS...ROUTE 22...ROUTE
219...ROUTE 220...ROUTE 422...STATE ROAD 453.

LAT...LON 4048 7893 4073 7830 4064 7777 4032 7853
      4038 7899

FORECASTER: KREKELER