Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 131, NWS State College, PA

July 7, 2015Warren County, Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at Jul 7, 2015, 6:50 PM EDT for Warren County, Pennsylvania. It was in force for 55 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jul 7, 2015, 6:50 PM EDT (22:50 UTC)
Expired
Jul 7, 2015, 7:45 PM EDT
In force
55 min
Issued by
NWS State College, PA
Area
Storm-based polygon

County Warren County, PA

The radar

The Buffalo radar (KBUF), 134 km from the middle of the area, began a volume at 22:51 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 10.8 hours before the alert went out and 133 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Buffalo Intl Airport, NY at 12:00Z on 2015-07-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Buffalo Intl Airport, NY at 12:00Z on 2015-07-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 50 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
946 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
50 m²/s²
0-3 km storm-relative helicity
75 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS State College, PA wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 7, 6:38 PM EDT, 12 minutes earlier.

Area forecast discussion, Jul 7, 6:38 PM EDT, 12 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
638 PM EDT TUE JUL 7 2015

.SYNOPSIS...
A WEAK RIDGE WILL BRING VERY WARM AND HUMID CONDITIONS
TO THE REGION TODAY. AN APPROACHING COLD FRONT WILL MOVE THROUGH
OVERNIGHT...THEN STALL OUT ALONG OR JUST SOUTH OF THE MASON DIXON
LINE FOR MUCH OR THE REST OF THE WEEK KEEPING UNSETTLED CONDITIONS
IN THE FORECAST FOR THE NEXT COUPLE OF DAYS. HIGH PRESSURE SHOULD
RETURN FOR FRIDAY AND BRING SLIGHTLY COOLER AND NOTABLY LESS HUMID
WEATHER WITH LITTLE CHANCE FOR RAIN.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
AN OVERACHIEVING BOWING LINE SEGMENT...AIDED BY A CELL MERGER OVER
THE NORTHWEST MOUNTAINS...PRODUCED A FAIRLY LONGLIVED PATH OF WIND
DAMAGE ACROSS MCKEAN AND POTTER COUNTIES EARLY THIS EVENING. THE
CLUSTER OF STORMS RESPONSIBLE FOR THESE ISOLATED SEVERE WIND GUSTS
WAS TRAVERSING MY NORTHERN TIER COUNTIES...AND THE BOW HAS MOVED
NORTH OF THE PA/NY BORDER.

ATTENTION SHIFTS UPSTREAM TO LOCALLY STRONG CELLS JUST WEST OF MY
CWA. CELL MOTION ORTHOGONAL TO INDIVIDUAL DOPPLERS MAKING SAMPLING
DIFFICULT. IN GENERAL...THIS ACTIVITY SHOULD BE WEAKENING AS IT
ENTERS MY NORTHWEST COUNTIES LATER THIS EVENING. SOME TRAINING
POTENTIAL EXISTS AS THE SLOW MOVING FRONT PROGRESSES
SOUTHEASTWARD.

ACCOMPANYING COLD FRONT WILL MOVE INTO THE NORTHWEST ZONES LATER
THIS EVENING AND SLOWLY SOUTHWARD ACROSS THE COMMONWEALTH
OVERNIGHT. SHOWER COVERAGE SHOULD DIMINISH AS THE FRONT MOVES
SOUTH.

TEMPERATURES WILL BE GENERALLY MILD OVERNIGHT AS MOST OF THE AREA
WILL BE CLOUDY AND HUMID WITH SCATTERED SHOWERS.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
THE SURFACE COLD FRONT WILL STALL OUT CLOSE TO THE MASON DIXON
LINE ON WEDNESDAY. THE CHANCE OF SHOWERS AND THUNDERSTORMS WILL
SHIFT TOWARDS THE SOUTHERN HALF OF PENNSYLVANIA TOMORROW. QPF
VALUES WILL BE LESS THAN A THIRD OF AN INCH IN OUR COUNTIES.

MAX TEMPS WEDNESDAY WILL BE AROUND 10 DEGREES COOLER THAN TODAY AS
CLOUDS WILL DOMINATE THE SKY.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
THE LINGERING QUASI-STATIONARY FRONTAL ZONE EXTENDING FROM THE
MID ATLANTIC COAST WWD INTO THE OHIO VALLEY IS EXPECTED TO REMAIN
A FOCUS FOR PCPN ON DAY 3/THURS. THERE IS REASONABLY GOOD MODEL
AGREEMENT IN A CONVECTIVELY ENHANCED PERTURBATION/SFC WAVE
EMERGING FROM THE SRN PLAINS AND PROGRESSING EWD AROUND THE
PERIPHERY OF A SUBTROPICAL RIDGE OVER THE SOUTHEAST STATES. THE
GLOBAL MODELS TEND TO HAVE A NORTHERN BIAS WITH QPF AXES ASSOCD
WITH THESE MESO FEATURES...AND THEREFORE FOLLOWED WPC LEAD WITH
CLUE FROM THE HI-RES MODELS IN SHIFTING MAX POPS SWD OF CONSENSUS.
THERE IS THE POTENTIAL FOR THIS FEATURE TO MAINTAIN INTENSITY OR
RE-INTENSIFY AS IT REACHES CENTRAL PA THURSDAY AFTERNOON..IN WHICH
CASE IT WOULD BE ACCOMPANIED BY SEVERE WX AND HEAVY RAINFALL
RISK. LATER FORECASTS SHOULD BE ABLE TO PROVIDE GREATER VISIBILITY
AND INCREASED CONFIDENCE IN THE EVOLUTION AND POTENTIAL IMPACTS
ASSOCD WITH THIS SYSTEM.

THE MEDIUM RANGE MODEL AND ENSEMBLE GUIDANCE REMAINS CONSISTENT
IN ITS PROJECTION THAT THE FLOW ALOFT WILL STEADILY EVOLVE TOWARD
AN AMPLIFIED TROUGH/RIDGE/TROUGH PATTERN FROM WEST TO EAST ACROSS
THE LOWER 48. THIS SHOULD OCCUR BY WAY OF NRN PAC ENERGY FEEDING
INTO A TROUGH ALONG THE WEST COAST...A STRENGTHENING UPPER RIDGE
THAT RETROGRADES WWD FROM THE SOUTHEAST INTO THE PLAINS EVENTUALLY
EXPANDING NWD OVER THE ROCKIES INTO WRN CANADA...AND DOWNSTREAM
TROUGHING FROM THE BUILDING RIDGE OVER THE EAST EXTENDING SWD FROM
HUDSON BY VORTEX.

A 24-48HR PERIOD OF DRY WEATHER...WHICH HAS BEEN QUITE ELUSIVE AS
OF LATE...COULD BE IN STORE FOR THE AREA BY THE END OF THE WEEK
AS WEAK RIDGING FOLLOWS IN THE WAKE OF THE D3 CONVECTIVE LOW. THE
PLACEMENT OF PIVOTING FRONTAL BOUNDARY AND ASSOCIATED MSTR/PW AXIS
WILL BE CRUCIAL FOR DETERMINING PCPN RISK INTO THE WEEKEND...WITH
THE LATEST MODEL CONSENSUS KEEPING MOST OF THE ACTIVITY TO THE NW
OR SW OF CENTRAL PA. THE OTHER FACTOR WILL BE WHAT HAPPENS TO
ENERGY EJECTING FROM UPPER LOW MOVING ONSHORE CA IN THE SHORT
RANGE. THERE IS REASONABLE AGREEMENT IN PRINCIPLE THAT THIS
ENERGY SHOULD ROUND THE BUILDING ROCKIES/HIGH PLAINS RIDGE AND
THEN HELP TO CARVE OUT THE DEVELOPING ERN TROUGH DOWNSTREAM.
HOWEVER SOLUTIONS HAVE NOT LOCKED ONTO HOW SHEARED THE ENERGY WILL
BECOME...WHICH ALONG WITH A FEW ADDITIONAL FACTORS LEADS TO
DIFFERENCES IN THE DEPTH OF THE TROUGH AND TIMING OF NEXT PCPN
OPPORTUNITY.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
MOST OF CWA REMAINS VFR THIS EVENING...AS REGION REMAINS IN THE
WARM SECTOR AHEAD OF AN APPROACHING COLD FRONT OVER THE OHIO
VALLEY. BUT THUNDERSTORMS ARE ALREADY IMPACTING THE NW MTNS AND
KBFD AT 22Z...BRINGING SHORT-LIVED REDUCTIONS TO BOTH CIG AND VSBY
ALONG WITH SOME GUSTY WINDS.

AS THE FRONT ENTERS NW PA THIS EVENING...SHOWERS AND THUNDERSTORMS
WILL CONTINUE TO IMPACT THE NW MTNS AND KBFD THROUGH THE EVENING
HOURS. EXPECT ANOTHER WAVE OF TSTMS TO SLIDE ACROSS THROUGH
03Z...FOLLOWED BY A COUPLE HOUR PERIOD OF STRATIFORM RAIN
WITH FROPA AS CIG RESTRICTIONS BEGIN.

AS THE COLD FRONT PUSHES SLOWLY SOUTH ACROSS THE AIRSPACE
OVERNIGHT...SCATTERED TO NUMEROUS SHOWERS/TSTMS WILL IMPACT
CENTRAL MTNS STARTING MID EVEING...WITH JUST SCT TSTMS POSS IN
THE SE OVERNIGHT. BY MORNING...CONDITIONS WILL BE MVFR/IFR IN ALL
BUT FAR SE. THE FRONT WILL SETTLE SOUTH WEDNESDAY BEFORE STALLING
OUT ALONG THE MASON DIXON LINE.

WAVES OF LOW PRESSURE WILL MOVE ALONG THE FRONT AND BRING PERIODS
OF SHOWERS/THUNDERSTORMS ALONG WITH REDUCED CONDITIONS INTO
THURSDAY.

OUTLOOK...

WED...SHOWERS/TSTMS LIKELY SOUTH...SCATTERED NORTH.

THU...SHOWERS/TSTMS LIKELY. CIG RESTRICTIONS LIKELY NORTH...LOCAL
RESTRICTIONS SOUTH.

FRI-SUN...MAINLY VFR. CHC OF SHOWERS/TSTMS SW 1/3 OF AIRSPACE.

&&

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

&&

SYNOPSIS...LA CORTE
NEAR TERM...DEVOIR/LA CORTE
SHORT TERM...LA CORTE
LONG TERM...GARTNER/STEINBUGL
AVIATION...RXR
Hazardous weather outlook, Jul 7, 5:33 AM EDT, 13 hours 17 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE STATE COLLEGE PA
533 AM EDT TUE JUL 7 2015

PAZ006-011-012-017>019-024>028-033>037-041-042-045-046-049>053-
056>059-063>066-080945-
POTTER-CAMERON-NORTHERN CLINTON-CLEARFIELD-NORTHERN CENTRE-
SOUTHERN CENTRE-CAMBRIA-BLAIR-HUNTINGDON-MIFFLIN-JUNIATA-SOMERSET-
BEDFORD-FULTON-FRANKLIN-TIOGA-NORTHERN LYCOMING-SULLIVAN-
SOUTHERN CLINTON-SOUTHERN LYCOMING-UNION-SNYDER-MONTOUR-
NORTHUMBERLAND-COLUMBIA-PERRY-DAUPHIN-SCHUYLKILL-LEBANON-CUMBERLAND-
ADAMS-YORK-LANCASTER-
533 AM EDT TUE JUL 7 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA.

.DAY ONE...TODAY AND TONIGHT.

THE PROBABILITY OF WIDESPREAD HAZARDOUS WEATHER IS LOW.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

A FEW WAVES OF LOW PRESSURE WILL RIDE EAST ALONG A FRONTAL
BOUNDARY THAT WILL BE STALLED OUT NEAR OR JUST TO THE SOUTH OF THE
MASON DIXON LINE. SHOWERS AND THUNDERSTORMS WILL ACCOMPANY EACH
WAVE OF LOW PRESSURE AND SOME OF THE STORMS DURING THE AFTERNOON
AND EARLY EVENING HOURS WEDNESDAY AND THURSDAY COULD PRODUCE
STRONG WIND GUSTS AND PERHAPS A FEW INSTANCES OF LARGE HAIL. THE
GREATEST THREAT FOR THE STRONGER STORMS WILL BE ACROSS THE
SOUTHERN HALF OF PENNSYLVANIA.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

PAZ004-005-010-080945-
WARREN-MCKEAN-ELK-
533 AM EDT TUE JUL 7 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA.

.DAY ONE...TODAY AND TONIGHT.

A COLD FRONT APPROACHING FROM THE GREAT LAKES WILL BRING
THUNDERSTORMS TO THE AREA LATE TODAY AND EARLY TONIGHT. THERE IS
A SLIGHT CHANCE THAT SOME OF THESE STORMS COULD PRODUCE LOCALIZED
DAMAGING WIND GUSTS OR LARGE HAIL.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

THE PROBABILITY OF WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

LAMBERT

In the hours before

Local storm report, Jul 7, 5:17 PM EDT, 1 hour 33 minutes before
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Local storm report, Jul 7, 5:25 PM EDT, 1 hour 25 minutes before
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Local storm report, Jul 7, 5:57 PM EDT, 53 minutes before
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<body>
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    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
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Special weather statement, Jul 7, 6:09 PM EDT, 41 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
609 PM EDT TUE JUL 7 2015

PAZ004-072300-
WARREN PA-
609 PM EDT TUE JUL 7 2015

...A STRONG THUNDERSTORM WILL AFFECT WARREN COUNTY UNTIL 700 PM
EDT...

AT 608 PM EDT...DOPPLER RADAR INDICATED A STRONG THUNDERSTORM NEAR
COLUMBUS...MOVING EAST AT 30 MPH.

50 MPH WIND GUSTS WILL BE POSSIBLE WITH THIS STORM.

THIS STRONG THUNDERSTORM WILL BE NEAR...
  SPRING CREEK AROUND 615 PM EDT.
  GARLAND AROUND 620 PM EDT.
  LOTTSVILLE AROUND 625 PM EDT.
  YOUNGSVILLE AROUND 635 PM EDT.
  RUSSELL AND WARREN AROUND 655 PM EDT.

OTHER LOCATIONS IMPACTED BY THIS STORM INCLUDE BEAR LAKE...STARBRICK
AND SUGAR GROVE.

LAT...LON 4200 7906 4179 7912 4177 7961 4200 7961
TIME...MOT...LOC 2208Z 258DEG 25KT 4191 7958

RXR
Local storm report, Jul 7, 6:33 PM EDT, 17 minutes before
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE STATE COLLEGE PA
633 PM EDT TUE JUL 07 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0510 PM     TSTM WND DMG     3 W KANE                41.66N  78.87W
07/07/2015                   MCKEAN             PA   911 CALL CENTER

            TREES DOWN

0530 PM     TSTM WND DMG     1 S LAFAYETTE           41.78N  78.68W
07/07/2015                   MCKEAN             PA   911 CALL CENTER

            TREES AND WIRES DOWN BLOCKING PINE RUN ROAD.

0610 PM     TSTM WND DMG     SHINGLEHOUSE            41.97N  78.19W
07/07/2015                   POTTER             PA   911 CALL CENTER

            TREES DOWN ON ELEVEN MILE ROAD.

&&

EVENT NUMBER CTP1500245 CTP1500247 CTP1500248

MACH
Local storm report, Jul 7, 6:39 PM EDT, 11 minutes before
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE STATE COLLEGE PA
639 PM EDT TUE JUL 07 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0510 PM     TSTM WND DMG     3 W KANE                41.66N  78.87W
07/07/2015                   MCKEAN             PA   911 CALL CENTER

            TREES DOWN

0530 PM     TSTM WND DMG     1 S LAFAYETTE           41.78N  78.68W
07/07/2015                   MCKEAN             PA   911 CALL CENTER

            TREES AND WIRES DOWN BLOCKING PINE RUN ROAD.

0610 PM     TSTM WND DMG     5 SE SHINGLEHOUSE       41.91N  78.12W
07/07/2015                   POTTER             PA   911 CALL CENTER

            TREES DOWN ON ELEVEN MILE ROAD.

&&

EVENT NUMBER CTP1500245 CTP1500247 CTP1500248

MACH

The office that day

Everything else NWS State College, PA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 6, 11:13 PM EDTSpecial Weather StatementCTPLancaster62 min
Jul 7, 3:57 PM EDTSpecial Weather StatementCTPWarren63 min
Jul 7, 4:36 PM EDTSevere Thunderstorm WarningCTPElk, McKean, Warren39 min
Jul 7, 5:15 PM EDTSevere Thunderstorm WarningCTPElk, McKean, Warren45 min
Jul 7, 5:41 PM EDTSevere Thunderstorm WarningCTPMcKean, Potter34 min
Jul 7, 6:09 PM EDTSpecial Weather StatementCTPWarren51 min
Jul 7, 6:56 PM EDTSpecial Weather StatementCTPTioga34 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2015Every severe thunderstorm warning in 2015

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.