Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 30, NWS Pittsburgh, PA

April 20, 2017Clarion County, Forest County, Pennsylvania

NWS Pittsburgh, PA issued this severe thunderstorm warning at Apr 20, 2017, 9:38 PM EDT for Clarion County, Forest County, Pennsylvania. It was in force for 22 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: Apr 20, 2017, 9:38 PM EDT (01:38 UTC)
Expired: Apr 20, 2017, 10:00 PM EDT
In force: 22 min
Issued by: NWS Pittsburgh, PA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Clarion County, PA, Forest County, PA

The radar

The Pittsburgh radar (KPBZ), 118 km from the middle of the area, began a volume at 01:39 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 00:00Z, 1.6 hours before the alert went out and 123 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: 901 J/kg
Mixed-layer CIN: -23 J/kg
Mixed-layer LCL: 1052 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 259 m²/s²
0-3 km storm-relative helicity: 395 m²/s²
Significant tornado parameter: 1.1
Supercell composite: 6.5

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 Apr 20, 9:06 PM EDT, 32 minutes earlier.

Area forecast discussion, Apr 20, 9:06 PM EDT, 32 minutes before

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Hazardous weather outlook, Apr 20, 9:11 PM EDT, 27 minutes before

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In the hours before

Local storm report, Apr 20, 5:21 PM EDT, 4 hours 17 minutes before

PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE PITTSBURGH PA
521 PM EDT THU APR 20 2017

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

1235 PM     HAIL             NEW KENSINGTON          40.57N  79.75W
04/20/2017  M1.25 INCH       WESTMORELAND       PA   SOCIAL MEDIA

            PHOTOS SUBMITTED THROUGH NWS FACEBOOK

1243 PM     HAIL             WEST NEW KENSINGTON     40.56N  79.77W
04/20/2017  M2.00 INCH       WESTMORELAND       PA   TRAINED SPOTTER

1245 PM     HAIL             ARNOLD                  40.58N  79.76W
04/20/2017  M1.00 INCH       WESTMORELAND       PA   TRAINED SPOTTER

1250 PM     HAIL             5 SE NEW KENSINGTON     40.52N  79.68W
04/20/2017  M1.00 INCH       WESTMORELAND       PA   TRAINED SPOTTER

0103 PM     HAIL             7 ESE NEW KENSINGTON    40.53N  79.63W
04/20/2017  M1.00 INCH       WESTMORELAND       PA   TRAINED SPOTTER

0108 PM     HAIL             2 SE NORTH WASHINGTON   40.51N  79.58W
04/20/2017  M1.50 INCH       WESTMORELAND       PA   PUBLIC

0115 PM     HAIL             2 SW SALINA             40.50N  79.53W
04/20/2017  M1.25 INCH       WESTMORELAND       PA   TRAINED SPOTTER

0223 PM     TSTM WND DMG     2 E WHITE OAK           40.34N  79.77W
04/20/2017                   WESTMORELAND       PA   911 CALL CENTER

            TREES DOWN ON CARPENTER LANE

0229 PM     TSTM WND DMG     NORTH IRWIN             40.33N  79.71W
04/20/2017                   WESTMORELAND       PA   911 CALL CENTER

            WIRES DOWN ALONG MAIN ST

0232 PM     TSTM WND DMG     CRANBERRY TWP           40.69N  80.10W
04/20/2017                   BUTLER             PA   TRAINED SPOTTER

            LARGE TREES REPORTED DOWN

0235 PM     TSTM WND DMG     1 S ARONA               40.26N  79.66W
04/20/2017                   WESTMORELAND       PA   911 CALL CENTER

            TREES DOWN ALONG LIBERTY HILL RD

0236 PM     TSTM WND DMG     1 NE JEANNETTE          40.34N  79.60W
04/20/2017                   WESTMORELAND       PA   911 CALL CENTER

            WIRES DOWN ALONG ALTMAN RD

0308 PM     TSTM WND DMG     2 N MILLBANK            40.29N  79.27W
04/20/2017                   WESTMORELAND       PA   911 CALL CENTER

            WIRES DOWN AT MATSON AND CLARK HOLLOW ROAD

0313 PM     HAIL             4 E CHICORA             40.95N  79.67W
04/20/2017  M1.00 INCH       ARMSTRONG          PA   TRAINED SPOTTER

0313 PM     TSTM WND GST     4 E CHICORA             40.95N  79.67W
04/20/2017  E50 MPH          ARMSTRONG          PA   TRAINED SPOTTER

0316 PM     HAIL             EAST BRADY              40.98N  79.61W
04/20/2017  M1.50 INCH       CLARION            PA   PUBLIC

0325 PM     HAIL             LIMESTONE               41.13N  79.33W
04/20/2017  M1.75 INCH       CLARION            PA   TRAINED SPOTTER

0435 PM     TSTM WND DMG     INDEPENDENCE            39.39N  79.87W
04/20/2017                   PRESTON            WV   911 CALL CENTER

            TREE DOWN

0450 PM     TSTM WND DMG     KINGWOOD                39.47N  79.68W
04/20/2017                   PRESTON            WV   911 CALL CENTER

            TREE DOWN

0455 PM     TSTM WND DMG     ALBRIGHT                39.49N  79.64W
04/20/2017                   PRESTON            WV   911 CALL CENTER

            TREE DOWN

&&

EVENT NUMBER PBZ1701322 PBZ1701318 PBZ1701319 PBZ1701317 PBZ1701320
PBZ1701323 PBZ1701321 PBZ1701324 PBZ1701325 PBZ1701328 PBZ1701326
PBZ1701327 PBZ1701333 PBZ1701329 PBZ1701330 PBZ1701331 PBZ1701332
PBZ1701334 PBZ1701335 PBZ1701336

XX

Special weather statement, Apr 20, 6:36 PM EDT, 3 hours 2 minutes before

Special Weather Statement
National Weather Service Pittsburgh PA
636 PM EDT THU APR 20 2017

OHZ048-057-202315-
Coshocton-Muskingum-
636 PM EDT THU APR 20 2017

...A STRONG THUNDERSTORM CAPABLE OF PRODUCING GUSTY WIND WILL AFFECT
COSHOCTON AND NORTHWESTERN MUSKINGUM COUNTIES...

At 635 PM EDT, a strong thunderstorm was located 8 miles east of
Utica, or 13 miles northeast of Newark, moving east at 50 mph.

Wind gusts up to 45 mph and brief heavy rain are possible with this
storm.

Locations impacted include...
Coshocton...                      West Lafayette...
Frazeysburg...                    Warsaw...
Conesville...                     Plainfield...
Nellie...                         Chili...
New Guilford...                   Walhonding...
Layland...                        Blissfield...

LAT...LON 4037 8219 4045 8197 4044 8173 4041 8171
      4037 8171 4037 8169 4022 8163 4022 8166
      4021 8167 4010 8219 4024 8218 4024 8220
TIME...MOT...LOC 2235Z 253DEG 42KT 4023 8228

CL

Special weather statement, Apr 20, 7:08 PM EDT, 2 hours 30 minutes before

Special Weather Statement
National Weather Service Pittsburgh PA
708 PM EDT THU APR 20 2017

OHZ057-058-202345-
Guernsey-Muskingum-
708 PM EDT THU APR 20 2017

...A LINE OF STRONG THUNDERSTORMS CAPABLE OF PRODUCING GUSTY WIND
WILL AFFECT SOUTHWESTERN GUERNSEY AND MUSKINGUM COUNTIES...

At 708 PM EDT, radar indicated strong thunderstorms were located
along a line extending from 6 miles south of Marne to 7 miles
northeast of Somerset to near Bremen. Movement was east at 45 mph.

Wind gusts up to 50 mph are possible with these storms.

Locations impacted include...
Zanesville...                     New Concord...
South Zanesville...               North Zanesville...
Philo...                          Pleasant Grove...
Gratiot...                        Fultonham...
Norwich...                        Cannelville...
High Hill...                      Chandlersville...

This includes  Interstate 70 in Ohio near mile marker 143, and
between mile
  markers 145 and 172.

LAT...LON 3995 8223 3995 8220 4005 8219 4014 8176
      3991 8163 3984 8168 3984 8170 3983 8169
      3976 8175 3977 8207 3982 8208 3982 8217
      3991 8216 3991 8223
TIME...MOT...LOC 2308Z 267DEG 38KT 3999 8227 3990 8223 3974 8235

CL

Special weather statement, Apr 20, 7:59 PM EDT, 1 hour 39 minutes before

Special Weather Statement
National Weather Service Pittsburgh PA
759 PM EDT THU APR 20 2017

OHZ049-058-059-068-210030-
Guernsey-Noble-Harrison-Belmont-
759 PM EDT THU APR 20 2017

...A STRONG THUNDERSTORM CAPABLE OF PRODUCING GUSTY WIND WILL AFFECT
SOUTHWESTERN HARRISON...GUERNSEY...NORTHWESTERN BELMONT AND
NORTHEASTERN NOBLE COUNTIES...

At 759 PM EDT, a strong thunderstorm was located near Cambridge,
moving east at 40 mph.

Wind gusts up to 55 mph are possible with this storm.

Locations impacted include...
Cambridge...                      Barnesville...
Freeport...                       Byesville...
Bethesda...                       Antrim...
Flushing...                       Quaker City...
Senecaville...                    Belmont...
Holloway...                       Lore City...

This includes the following highways...
  Interstate 70 in Ohio between mile markers 177 and 210.

  Interstate 77 in Ohio between mile markers 39 and 53.

LAT...LON 3992 8159 4009 8165 4029 8113 3994 8096
TIME...MOT...LOC 2359Z 256DEG 36KT 4004 8149

CL

Special weather statement, Apr 20, 8:27 PM EDT, 1 hour 11 minutes before

Special Weather Statement
National Weather Service Pittsburgh PA
827 PM EDT THU APR 20 2017

PAZ008-009-210100-
Forest-Venango-
827 PM EDT THU APR 20 2017

...A STRONG THUNDERSTORM CAPABLE OF PRODUCING SMALL HAIL AND GUSTY
WIND WILL AFFECT NORTHERN VENANGO AND NORTHWESTERN FOREST COUNTIES...

At 826 PM EDT, a strong thunderstorm was located 7 miles southeast of
Guys Mills, or 10 miles north of Franklin, moving east at 40 mph.

Wind gusts up to 45 mph and small hail are possible with this storm.

Locations impacted include...
Sugarcreek...                     Tionesta...
Rouseville...                     Cooperstown...
Pleasantville...                  Utica...
West Hickory...                   Oil Creek State Park...
East Hickory...                   Starr...

This storm may intensify, so monitor local radio or television
stations for additional information and possible warnings from the
National Weather Service.

LAT...LON 4151 7936 4143 7995 4151 7997 4153 7994
      4154 7994 4154 7993 4156 7991 4156 7989
      4157 7989 4157 7987 4158 7987 4160 7983
      4162 7983 4162 7961 4163 7950 4163 7940
TIME...MOT...LOC 0026Z 256DEG 34KT 4154 7988

CL

Special weather statement, Apr 20, 9:15 PM EDT, 23 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 20, 8:27 PM EDT	Special Weather Statement	PBZ	Venango	33 min
Apr 20, 8:40 PM EDT	Severe Thunderstorm Warning	PBZ	Clarion, Forest, Venango	50 min
Apr 20, 9:15 PM EDT	Special Weather Statement	PBZ	Greene	30 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2017 Every severe thunderstorm warning in 2017

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.