Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 38, NWS Pittsburgh, PA

May 31, 2015Clarion County, Jefferson County, Pennsylvania

NWS Pittsburgh, PA issued this severe thunderstorm warning at May 31, 2015, 2:40 PM EDT for Clarion County, Jefferson County, Pennsylvania. It was in force for 35 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: May 31, 2015, 2:40 PM EDT (18:40 UTC)
Expired: May 31, 2015, 3:15 PM EDT
In force: 35 min
Issued by: NWS Pittsburgh, PA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Clarion County, PA, Jefferson County, PA

The radar

The State College radar (KCCX), 105 km from the middle of the area, began a volume at 18:41 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

Pittsburgh, PA (KAGC), launched 12:00Z, 6.7 hours before the alert went out and 112 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 78 J/kg
Mixed-layer CIN: -66 J/kg
Mixed-layer LCL: 964 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 146 m²/s²
0-3 km storm-relative helicity: 172 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

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 Pittsburgh, PA wrote its last area forecast discussion before this severe thunderstorm warning went out at May 31, 12:26 PM EDT, 2 hours 14 minutes earlier.

Area forecast discussion, May 31, 12:26 PM EDT, 2 hours 14 minutes before

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Hazardous weather outlook, May 31, 9:56 AM EDT, 4 hours 44 minutes before

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE PITTSBURGH PA
956 AM EDT SUN MAY 31 2015

MDZ001-OHZ039>041-048>050-057>059-068-069-PAZ007>009-013>016-020>023-
029-031-073>076-WVZ001>004-012-021>023-041-011400-
GARRETT-TUSCARAWAS-CARROLL-COLUMBIANA-COSHOCTON-HARRISON-
JEFFERSON OH-MUSKINGUM-GUERNSEY-BELMONT-NOBLE-MONROE-MERCER-VENANGO-
FOREST-LAWRENCE-BUTLER-CLARION-JEFFERSON PA-BEAVER-ALLEGHENY-
ARMSTRONG-INDIANA-WASHINGTON-GREENE-WESTMORELAND-WESTMORELAND RIDGES-
FAYETTE-FAYETTE RIDGES-HANCOCK-BROOKE-OHIO-MARSHALL-WETZEL-MARION-
MONONGALIA-PRESTON-TUCKER-
956 AM EDT SUN MAY 31 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN MARYLAND...EAST
CENTRAL OHIO...NORTHWEST PENNSYLVANIA...SOUTHWEST
PENNSYLVANIA...WEST CENTRAL PENNSYLVANIA...NORTHERN WEST VIRGINIA
AND NORTHERN PANHANDLE OF WEST VIRGINIA.

.DAY ONE...TODAY AND TONIGHT.

THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS TODAY...WITH THE
MAIN THREATS BEING DAMAGING WINDS AND LARGE HAIL. ISOLATED
TORNADOES AND LOCALIZED FLOODING ARE ALSO POSSIBLE.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

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

07

In the hours before

Local storm report, May 31, 11:42 AM EDT, 2 hours 58 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PITTSBURGH PA
1142 AM EDT SUN MAY 31 2015

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

1120 AM     HAIL             7 NW SIGEL              41.35N 79.22W
05/31/2015  M1.00 INCH       CLARION            PA   PARK/FOREST SRVC

            REPORTED AT COOK FOREST STATE PARK

&&

JD

Local storm report, May 31, 12:09 PM EDT, 2 hours 31 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PITTSBURGH PA
1209 PM EDT SUN MAY 31 2015

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

1135 AM     HAIL             4 WNW SIGEL             41.31N 79.19W
05/31/2015  M1.00 INCH       JEFFERSON          PA   PUBLIC

            REPORTED AT DOUBLE DIAMOND DEER RANCH

&&

JD

Special weather statement, May 31, 2:04 PM EDT, 36 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PITTSBURGH PA
204 PM EDT SUN MAY 31 2015

PAZ029-031-WVZ004-311845-
WASHINGTON-GREENE-MARSHALL-
204 PM EDT SUN MAY 31 2015

...A STRONG THUNDERSTORM WILL AFFECT THE AREA...

AT 203 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR IN PITTSBURGH
SHOWED A STRONG THUNDERSTORM WAS NEAR CAMERON...OR 16 MILES
SOUTHEAST OF MOUNDSVILLE...MOVING NORTHEAST AT 30 MPH.

WINDS IN EXCESS OF 40 MPH AND NICKEL SIZE HAIL ARE POSSIBLE WITH THIS
STORM.

LOCATIONS IMPACTED INCLUDE...
WAYNESBURG...JEFFERSON BORO...ROGERSVILLE...MARIANNA...ALEPPO...NEW
FREEPORT AND AMITY.

THIS INCLUDES  INTERSTATE 79 IN PENNSYLVANIA BETWEEN MILE MARKERS 8
AND 21...AND BETWEEN MILE MARKERS 22 AND 25.

LAT...LON 3979 8059 4008 8015 3984 7998 3972 8059
TIME...MOT...LOC 1803Z 240DEG 25KT 3979 8048

07

Special weather statement, May 31, 2:20 PM EDT, 20 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PITTSBURGH PA
220 PM EDT SUN MAY 31 2015

PAZ009-015-016-311845-
JEFFERSON-CLARION-FOREST-
220 PM EDT SUN MAY 31 2015

...A STRONG THUNDERSTORM WILL AFFECT NORTHWESTERN JEFFERSON...EASTERN
FOREST AND NORTHEASTERN CLARION COUNTIES...

AT 219 PM EDT...A STRONG THUNDERSTORM WAS 10 MILES SOUTHWEST OF
MARIENVILLE...MOVING NORTHEAST AT 35 MPH.

WIND GUSTS UP TO 50 MPH AND NICKEL SIZE HAIL ARE POSSIBLE WITH THIS
STORM.

LOCATIONS IMPACTED INCLUDE...
MARIENVILLE...LEEPER...FISHER...COOK FOREST STATE PARK...CLEAR CREEK
STATE PARK AND CLARINGTON.

LAT...LON 4144 7896 4144 7897 4145 7898 4145 7906
      4142 7907 4142 7909 4134 7909 4135 7908
      4136 7903 4135 7902 4138 7897 4136 7895
      4123 7923 4137 7937 4163 7900 4163 7896
TIME...MOT...LOC 1819Z 233DEG 29KT 4135 7923

34

Local storm report, May 31, 2:26 PM EDT, 14 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PITTSBURGH PA
226 PM EDT SUN MAY 31 2015

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

0208 PM     HAIL             8 WNW SIGEL             41.33N 79.26W
05/31/2015  M0.88 INCH       CLARION            PA   TRAINED SPOTTER

&&

JD

The office that day

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

Issued	Product	Office	Counties	Lasted
May 31, 8:34 AM EDT	Special Weather Statement	PBZ	Lawrence, Mercer	26 min
May 31, 11:05 AM EDT	Severe Thunderstorm Warning	PBZ	Clarion, Forest, Jefferson	25 min
May 31, 11:30 AM EDT	Severe Thunderstorm Warning	PBZ	Clarion, Forest, Jefferson	30 min
May 31, 1:26 PM EDT	Severe Thunderstorm Warning	PBZ	Butler, Clarion, Venango	34 min
May 31, 2:04 PM EDT	Special Weather Statement	PBZ	Greene	41 min
May 31, 2:20 PM EDT	Special Weather Statement	PBZ	Forest	25 min
May 31, 4:00 PM EDT	Severe Thunderstorm Warning	PBZ	Beaver	30 min
May 31, 4:29 PM EDT	Severe Thunderstorm Warning	PBZ	Beaver, Butler, Lawrence	31 min
May 31, 4:41 PM EDT	Areal Flood Advisory	PBZ	Mercer	6 hr
May 31, 5:41 PM EDT	Severe Thunderstorm Warning	PBZ	Greene, Washington	27 min
May 31, 6:11 PM EDT	Special Weather Statement	PBZ	Clarion	64 min
May 31, 6:35 PM EDT	Severe Thunderstorm Warning	PBZ	Armstrong, Clarion, Jefferson	55 min
May 31, 6:45 PM EDT	Special Weather Statement	PBZ	Allegheny	45 min
May 31, 7:30 PM EDT	Special Weather Statement	PBZ	Armstrong, Jefferson	45 min
May 31, 7:39 PM EDT	Severe Thunderstorm Warning	PBZ	Indiana, Jefferson	36 min
May 31, 7:48 AM EDT	Special Weather Statement	PBZ	Columbiana	27 min
May 31, 6:42 PM EDT	Special Weather Statement	PBZ	Preston	63 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2015 Every 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.