Severe Thunderstorm Warning 31, NWS State College, PA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
319 PM EDT FRI MAY 14 2010

.SYNOPSIS...
A COLD FRONT STRETCHING FROM THE FINGER LAKES REGION...THROUGH
NORTHWESTERN PENNSYLVANIA LATE THIS AFTERNOON WILL PUSH SOUTHEAST
ACROSS THE COMMONWEALTH LATE TODAY AND THIS EVENING. SCATTERED
SHOWERS AND THUNDERSTORMS WILL OCCUR ALONG AND AHEAD OF THE FRONT.
HIGH PRESSURE WILL BUILD EAST INTO THE STATE FOR THE WEEKEND
BRINGING DRY WEATHER WITH NEAR TO SLIGHTLY BELOW TEMPERATURES.
THE NEXT LOW PRESSURE AREA WILL APPROACH FROM THE OHIO VALLEY
EARLY NEXT WEEK. THIS SLOW MOVING WEATHER SYSTEM WILL BRING
SEVERAL PERIODS OF RAIN MONDAY THROUGH WEDNESDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
SVR TSTM WATCH 173 ISSUED RECENTLY FOR APPROX THE SOUTHERN HALF OF
PENN. A LENGTHY...BROKEN LINE OF HIGHLY SHEARED (AND SO FAR LOW-
TOPPED) TSRA STRETCHED ALONG AND JUST SE OF A COLD FRONT FROM NEAR
KIPT TO KIDI AT 19Z.

THE TSRA WILL BE DRIFTING INTO A MUCH BETTER ENVIRONMENT
(INSTABILITY AND LOW LEVEL SHEAR WISE) ACROSS LOWER SUSQ VALLEY
AFTER 20Z. 18Z RUC 0-1KM EHI WILL BE A HEALTHY 2-3 M2/S2 ACROSS
THE REGION NEAR AND TO THE EAST OF A KSEG TO KTHV LINE THROUGH
ABOUT 22Z. THEREFORE...SOME STORMS ENTERING THIS BETTER
CONVECTIVE ENVIRONMENT WILL DEVELOP ROTATION AND STRONGER UPDRAFTS
LEADING TO LOCALIZED LARGE HAIL/STRAIGHT LINE WINDS AND PERHAPS
EVEN A BRIEF TORNADO.

ACROSS THE NW HALF OF THE STATE...MOSTLY SUNNY SKIES WILL PREVAIL
THROUGH THE REMAINDER OF THE DAY WITH NOTHING MORE THAN A FEW
MINUTE SHOWER NEAR INTERSTATE THROUGH 21Z.

THIS EVENING THROUGH THE OVERNIGHT...CLEARING SKIES AND A 5 TO 10
KT WEST TO NW BREEZE WILL YIELD NEAR TO SLIGHTLY ABOVE NORMAL MIN
TEMPS. LOWS AT DAYBREAK SATURDAY WILL RANGE FROM THE L40S ACROSS
THE NW MTNS...TO THE MID 50S ACROSS THE LWR SUSQ VALLEY.

BASIN AVERAGE RAINFALL THROUGH EARLY THIS EVENING WILL RANGE FROM
JUST A FEW HUNDREDTHS OF AN INCH NEAR A KIDI TO KUNV AND KAVP
LINE...TO BETWEEN 0.10 AND 0.25 OF AN INCH ACROSS THE SOUTHERN
TIER COUNTIES.

&&

.SHORT TERM /SATURDAY/...
HIGH PRESSURE BUILDS INTO THE REGION SATURDAY...BRINGING MOSTLY
SUNNY SKIES CENTRAL AND SOUTH...WITH A FEW PERIODS OF BKN SKIES
ACROSS THE MTNS. THE VERTICAL MIXING DEPTH WILL INCREASE TO 5-6
KFT AGL DURING THE LATE MORNING AND AFTERNOON HOURS...TAPPING SOME
25 KT WIND WNW WINDS ALOFT AND TRANSPORTING THEM TO THE SFC IN
GUSTS.

MAX TEMPS SATURDAY WILL BE IN THE U50S TO MID 60S ACROSS THE
MTNS...AND U60S TO LOWER 70S ELSEWHERE.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
MIN TEMPS WILL BE SETTLING INTO THE MID 30S ACROSS NRN PENN SAT
NIGHT...AND U30S TO MID 40S ACROSS THE CENTRAL AND SOUTH UNDER
CLEAR SKIES WITH DIMINISHING WIND. SCATTERED FROST IS POSSIBLE
ACROSS THE NRN MTNS LATE SAT NIGHT THROUGH SHORTLY AFTER DAYBREAK
SUNDAY.

LGT WINDS AND FAIR WX EXPECTED SUNDAY WITH SFC HIGH PRES OVER THE
REGION. THE HIGH WILL SLIDE OFF THE MID ATLC COAST AS LOW
PRESSURE MOVES EWD FROM THE PLAINS/MID MS VLY INTO THE OH VLY/LWR
LKS EARLY NEXT WEEK...BRINGING THE NEXT CHANCE FOR RAIN. MEDIUM
RANGE MODEL/ENSEMBLE GUIDANCE AND HPC PROGS SUGGEST THE SYSTEM
WILL OCCLUDE AND CONTINUE UNSETTLED CONDITIONS INTO THE MIDDLE OF
NEXT WEEK.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
MAINLY VFR FLYING CONDITIONS EXPECTED FROM LATE TODAY RIGHT
THROUGH THE WEEKEND ACROSS THE NRN 2/3RDS OF THE STATE.

SCTD MVFR TO HIGHLY LOCALIZED TO IFR CIGS AND VSBYS WILL OCCUR
ACROSS THE SOUTHERN TIER OF PENN IN SHOWERS/THUNDERSTORMS THROUGH
DUSK. AFTERWARD...VFR FOR THE NEXT 48-60 HOURS.

THE ONLY OTHER FLYING IMPACT FOR THE WEEKEND WILL BE A GUSTY WNW
WIND OF 15 TO 25 KTS...AND TURBULENT MIXING AFFECTING TAKEOFF AND
FAP FROM ABOUT 12Z SAT THROUGH 22Z SAT.

OUTLOOK...
SUN...VFR.
MON-WED...MVFR WITH LOCALIZED IFR...AND POOR FLYING CONDS. SCT
SHRA / ISO TSRA.

&&

.FIRE WEATHER...
MIN RELATIVE HUMIDITY WILL DIP TO 30-40 PERCENT SATURDAY...AND
COMBINE WITH A GUSTY 15 TO 25 MPH WEST NORTHWEST WIND AND DRY FINE
FUELS TO BRING A SLIGHTLY ELEVATED POTENTIAL FOR WILDFIRE
GROWTH/SPREAD.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
SVR THUNDERSTORM WATCH 173 FOR SOUTHERN PENN THROUGH 01Z SATURDAY.

&&

SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...FITZGERALD/STEINBUGL
AVIATION...LAMBERT
FIRE WEATHER...LAMBERT

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE STATE COLLEGE PA
243 PM EDT FRI MAY 14 2010

PAZ004>006-010>012-017>019-037-041-042-045-046-049-151845-
WARREN-MCKEAN-POTTER-ELK-CAMERON-NORTHERN CLINTON-CLEARFIELD-
NORTHERN CENTRE-SOUTHERN CENTRE-TIOGA-NORTHERN LYCOMING-SULLIVAN-
SOUTHERN CLINTON-SOUTHERN LYCOMING-UNION-
243 PM EDT FRI MAY 14 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

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

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

PAZ024>028-033>036-050>053-056>059-063>066-151845-
CAMBRIA-BLAIR-HUNTINGDON-MIFFLIN-JUNIATA-SOMERSET-BEDFORD-FULTON-
FRANKLIN-SNYDER-MONTOUR-NORTHUMBERLAND-COLUMBIA-PERRY-DAUPHIN-
SCHUYLKILL-LEBANON-CUMBERLAND-ADAMS-YORK-LANCASTER-
243 PM EDT FRI MAY 14 2010

...SEVERE THUNDERSTORM WATCH 173 IN EFFECT UNTIL 9 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.

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

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THROUGH EARLY THIS EVENING.

LAMBERT

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1150 AM EDT FRI MAY 14 2010

PAZ026-033>036-141615-
BEDFORD PA-FRANKLIN PA-FULTON PA-HUNTINGDON PA-SOMERSET PA-
1150 AM EDT FRI MAY 14 2010

...A DEVELOPING THUNDERSTORM WILL AFFECT CENTRAL BEDFORD...CENTRAL
FRANKLIN...EAST CENTRAL SOMERSET...NORTHERN FULTON AND SOUTH CENTRAL
HUNTINGDON COUNTIES...

AT 1139 AM EDT...A DEVELOPING THUNDERSTORM WAS NEAR WINDBER...MOVING
EAST AT 50 MPH. THIS CELL WAS WITHIN A LINE OF INTENSIFYING SHOWERS
LOCATED FROM ROCK SPRINGS TO SEVEN SPRINGS.

THE STORM SHOULD PRODUCE LIGHTNING BY NOONTIME...AND MAY WIND UP
PRODUCING WIND GUSTS TO 40 MPH AND SMALL HAIL WITHIN THE NEXT 45
MINUTES. THIS STORM WILL BE NEAR MANNS CHOICE AROUND 1155 AM...
CESSNA AROUND NOON...EVERETT AROUND 1205 PM...BREEZEWOOD AROUND 1210
PM AND VALLEY-HI AROUND 1215 PM.

THIS WILL IMPACT THE FOLLOWING CENTRAL PENNSYLVANIA INTERSTATES...THE
PENNSYLVANIA TURNPIKE BETWEEN MILE MARKERS 134 AND 194...I-70 BETWEEN
MILE MARKERS 147 AND 151...I-81 BETWEEN MILE MARKERS 12 AND 23...I-99
BETWEEN MILE MARKERS 0 AND 8.

THIS WILL ALSO IMPACT THE FOLLOWING MAJOR ROADS...ROUTE 11...ROUTE
30...ROUTE 220...ROUTE 522.

LAT...LON 4000 7883 4018 7881 4014 7759 4012 7756
      4009 7756 4006 7754 3987 7756

EXPERIMENTAL

FORECASTER: DEVOIR

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1252 PM EDT FRI MAY 14 2010

PAZ026-036-056-063-141715-
CUMBERLAND PA-FRANKLIN PA-HUNTINGDON PA-PERRY PA-
1252 PM EDT FRI MAY 14 2010

...A STRONG THUNDERSTORM WILL AFFECT NORTH CENTRAL FRANKLIN...
NORTHERN CUMBERLAND...SOUTHEASTERN HUNTINGDON AND SOUTHERN PERRY
COUNTIES...

AT 1250 PM EDT...A STRONG THUNDERSTORM WAS 20 MILES SOUTH OF
HUNTINGDON...MOVING EAST AT 35 MPH.

WIND GUSTS TO 40 MPH AND SMALL HAIL ARE POSSIBLE WITH THIS STORM.
THIS STORM WILL BE NEAR DOYLESBURG AROUND 110 PM AND BIG SPRING STATE
PARK AROUND 115 PM.

THIS WILL IMPACT THE FOLLOWING CENTRAL PENNSYLVANIA INTERSTATES...THE
PENNSYLVANIA TURNPIKE BETWEEN MILE MARKERS 191 AND 233...I-81 BETWEEN
MILE MARKERS 36 AND 57.

THIS WILL ALSO IMPACT THE FOLLOWING MAJOR ROADS...ROUTE 11...ROUTE
522.

LAT...LON 4012 7803 4029 7805 4032 7773 4027 7770
      4033 7764 4039 7705 4015 7703 4012 7707
      4011 7800

EXPERIMENTAL

FORECASTER: DEVOIR

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
110 PM EDT FRI MAY 14 2010

PAZ035-036-063-064-141745-
ADAMS PA-CUMBERLAND PA-FRANKLIN PA-FULTON PA-
110 PM EDT FRI MAY 14 2010

...A STRONG THUNDERSTORM WILL AFFECT CENTRAL FRANKLIN...NORTHEASTERN
FULTON...SOUTHWESTERN CUMBERLAND AND WEST CENTRAL ADAMS COUNTIES...

AT 102 PM EDT...A STRONG THUNDERSTORM WAS NEAR BREEZEWOOD...MOVING
EAST AT 50 MPH.

WIND GUSTS TO 40 MPH AND SMALL HAIL ARE POSSIBLE WITH THIS STORM.
THIS STORM WILL BE NEAR FANNETTSBURG AROUND 120 PM...WILLOW HILL
AROUND 125 PM...UPPER STRASBURG AROUND 130 PM...SCOTLAND AROUND 135
PM AND SHIPPENSBURG AROUND 140 PM.

THIS WILL IMPACT THE FOLLOWING CENTRAL PENNSYLVANIA INTERSTATES...THE
PENNSYLVANIA TURNPIKE BETWEEN MILE MARKERS 169 AND 190...I-81 BETWEEN
MILE MARKERS 14 AND 35.

THIS WILL ALSO IMPACT THE FOLLOWING MAJOR ROADS...ROUTE 11...ROUTE
30...ROUTE 522.

LAT...LON 3993 7814 4011 7813 4011 7795 4007 7786
      4011 7783 4011 7738 3989 7739

EXPERIMENTAL

FORECASTER: DEVOIR

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
158 PM EDT FRI MAY 14 2010

PAZ049-051>053-141830-
COLUMBIA PA-MONTOUR PA-NORTHUMBERLAND PA-UNION PA-
158 PM EDT FRI MAY 14 2010

...A THUNDERSTORM WILL AFFECT CENTRAL COLUMBIA...MONTOUR...
NORTHEASTERN UNION AND NORTHERN NORTHUMBERLAND COUNTIES...

AT 148 PM EDT...A THUNDERSTORM WAS NEAR MIFFLINBURG...MOVING EAST AT
50 MPH.

THE STORM MAY PRODUCE GUSTY WINDS TO 40 MPH AND SMALL HAIL. THIS
STORM WILL BE NEAR MILTON AROUND 205 PM...WEST MILTON AROUND 210
PM...WASHINGTONVILLE AROUND 215 PM...JERSEYTOWN AROUND 220
PM...MILLVILLE AROUND 225 PM AND ORANGEVILLE AROUND 230 PM.

THIS WILL IMPACT THE FOLLOWING CENTRAL PENNSYLVANIA INTERSTATES...
I-80 BETWEEN MILE MARKERS 198 AND 240...I-180 BETWEEN MILE MARKERS 1
AND 5.

THIS WILL ALSO IMPACT THE FOLLOWING MAJOR ROADS...STATE HIGHWAY
147...ROUTE 11...ROUTE 15...STATE ROAD 45.

LAT...LON 4094 7633 4091 7708 4108 7710 4109 7698
      4110 7697 4117 7636

EXPERIMENTAL

FORECASTER: DEVOIR

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
259 PM EDT FRI MAY 14 2010

PAZ024>026-141945-
BLAIR PA-CAMBRIA PA-HUNTINGDON PA-
259 PM EDT FRI MAY 14 2010

...A STRONG THUNDERSTORM WILL AFFECT CENTRAL BLAIR...CENTRAL CAMBRIA
AND NORTHWESTERN HUNTINGDON COUNTIES...

AT 253 PM EDT...A STRONG THUNDERSTORM WAS NEAR NANTY-GLO...MOVING
EAST AT 40 MPH.

WIND GUSTS TO 40 MPH AND SMALL HAIL ARE POSSIBLE WITH THIS STORM.
THIS STORM WILL BE NEAR LILLY...LORETTO...CASSANDRA...AND CHEST
SPRINGS AROUND 305 PM...TUNNELHILL...GALLITZIN...AND ASHVILLE AROUND
310 PM...HORSESHOE CURVE AROUND 315 PM...HOLLIDAYSBURG AND
DUNCANSVILLE AROUND 320 PM.

THIS WILL IMPACT I-99 BETWEEN MILE MARKERS 24 AND 45.

THIS WILL ALSO IMPACT THE FOLLOWING MAJOR ROADS...ROUTE 22...ROUTE
219...ROUTE 220...ROUTE 422...ROUTE 522...STATE ROAD 453.

LAT...LON 4057 7881 4070 7788 4045 7787 4042 7790
      4040 7787 4034 7787 4041 7882

EXPERIMENTAL

FORECASTER: DEVOIR