Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2016

Severe Thunderstorm Warning 117, NWS Pittsburgh, PA

August 28, 2016Jefferson County, Pennsylvania

NWS Pittsburgh, PA issued this severe thunderstorm warning at Aug 28, 2016, 2:34 PM EDT for Jefferson County, Pennsylvania. It was in force for 11 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: Aug 28, 2016, 2:34 PM EDT (18:34 UTC)
Expired: Aug 28, 2016, 2:45 PM EDT
In force: 11 min
Issued by: NWS Pittsburgh, PA
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County Jefferson County, PA

The radar

The State College radar (KCCX), 87 km from the middle of the area, began a volume at 18:36 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, 6.6 hours before the alert went out and 122 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: 820 J/kg
Mixed-layer CIN: -76 J/kg
Mixed-layer LCL: 1215 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 41 m²/s²
0-3 km storm-relative helicity: 60 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

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 Aug 28, 1:52 PM EDT, 42 minutes earlier.

Area forecast discussion, Aug 28, 1:52 PM EDT, 42 minutes before

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Hazardous weather outlook, Aug 28, 3:27 AM EDT, 11 hours 7 minutes before

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In the hours before

Special weather statement, Aug 28, 2:20 PM EDT, 14 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PITTSBURGH PA
220 PM EDT SUN AUG 28 2016

PAZ016-281845-
JEFFERSON-
220 PM EDT SUN AUG 28 2016

...A STRONG THUNDERSTORM WILL AFFECT CENTRAL JEFFERSON COUNTY...

AT 219 PM EDT...A STRONG THUNDERSTORM WAS LOCATED NEAR BROOKVILLE...
MOVING NORTHEAST AT 20 MPH.

WINDS IN EXCESS OF 40 MPH ARE POSSIBLE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
BROOKVILLE...REYNOLDSVILLE...SYKESVILLE...SUMMERVILLE...WORTHVILLE
AND ANITA.

THIS INCLUDES  INTERSTATE 80 IN PENNSYLVANIA BETWEEN MILE MARKERS 78
AND 93.

LAT...LON 4095 7915 4106 7922 4113 7921 4128 7891
      4110 7880 4102 7880
TIME...MOT...LOC 1819Z 245DEG 16KT 4106 7912

34

Special weather statement, Aug 28, 2:27 PM EDT, 7 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PITTSBURGH PA
227 PM EDT SUN AUG 28 2016

PAZ016-281845-
JEFFERSON-
227 PM EDT SUN AUG 28 2016

...A STRONG THUNDERSTORM WILL AFFECT NORTHEASTERN JEFFERSON COUNTY...

AT 227 PM EDT...A STRONG THUNDERSTORM WAS LOCATED OVER BROCKWAY...OR
9 MILES NORTH OF DUBOIS...MOVING EAST AT 10 MPH.

WIND GUSTS UP TO 50 MPH ARE POSSIBLE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
BROCKWAY.

LAT...LON 4120 7877 4118 7878 4120 7886 4133 7888
      4126 7874 4123 7874 4123 7871 4120 7871
TIME...MOT...LOC 1827Z 271DEG 10KT 4125 7881

34

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 28, 2:20 PM EDT	Special Weather Statement	PBZ	Jefferson	25 min
Aug 28, 2:27 PM EDT	Special Weather Statement	PBZ	Jefferson	18 min
Aug 28, 5:04 PM EDT	Special Weather Statement	PBZ	Jefferson	56 min
Aug 28, 5:31 PM EDT	Severe Thunderstorm Warning	PBZ	Beaver	59 min
Aug 28, 5:37 PM EDT	Areal Flood Warning	PBZ	Clarion, Forest, Jefferson	4 hr
Aug 28, 5:44 PM EDT	Areal Flood Warning	PBZ	Beaver, Lawrence	3 hr
Aug 28, 5:51 PM EDT	Special Weather Statement	PBZ	Jefferson	54 min
Aug 28, 6:16 PM EDT	Severe Thunderstorm Warning	PBZ	Allegheny	44 min
Aug 28, 6:29 PM EDT	Areal Flood Warning	PBZ	Allegheny	3 hr
Aug 28, 6:34 PM EDT	Areal Flood Warning	PBZ	Jefferson	116 min
Aug 28, 6:57 PM EDT	Areal Flood Warning	PBZ	Clarion	2 hr
Aug 28, 7:02 PM EDT	Severe Thunderstorm Warning	PBZ	Allegheny	28 min
Aug 28, 7:04 PM EDT	Severe Thunderstorm Warning	PBZ	Greene, Washington	26 min
Aug 28, 7:13 PM EDT	Areal Flood Warning	PBZ	Allegheny, Westmoreland	3 hr
Aug 28, 7:22 PM EDT	Special Weather Statement	PBZ	Westmoreland	53 min
Aug 28, 7:34 PM EDT	Severe Thunderstorm Warning	PBZ	Allegheny, Washington	56 min
Aug 28, 7:35 PM EDT	Areal Flood Warning	PBZ	Allegheny, Greene, Washington	3 hr
Aug 28, 7:45 PM EDT	Special Weather Statement	PBZ	Washington	60 min
Aug 28, 7:51 PM EDT	Special Weather Statement	PBZ	Jefferson	54 min
Aug 28, 7:52 PM EDT	Areal Flood Warning	PBZ	Fayette, Westmoreland	6 hr
Aug 28, 4:57 PM EDT	Special Weather Statement	PBZ	Columbiana	63 min
Aug 28, 5:17 PM EDT	Special Weather Statement	PBZ	Carroll	43 min
Aug 28, 6:36 PM EDT	Special Weather Statement	PBZ	Carroll	54 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2016 Every severe thunderstorm warning in 2016

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.