Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 276, NWS State College, PA

September 15, 20214 counties in Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at Sep 15, 2021, 2:54 PM EDT for 4 counties in Pennsylvania. It was in force for 36 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Sep 15, 2021, 2:54 PM EDT (18:54 UTC)
Expired
Sep 15, 2021, 3:30 PM EDT
In force
36 min
Issued by
NWS State College, PA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Clinton County, PA, Lycoming County, PA, Northumberland County, PA, Union County, PA

The radar

The State College radar (KCCX), 92 km from the middle of the area, began a volume at 18:53 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Sep 15, 11:55 AM EDTSevere Thunderstorm WatchSPC8 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 6.9 hours before the alert went out and 241 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, Washington/Dulle, VA at 12:00Z on 2021-09-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 13 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 12:00Z on 2021-09-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 73 square meters per square second.193958Sfc1 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
13 J/kg
Mixed-layer CIN
-270 J/kg
Mixed-layer LCL
1457 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
73 m²/s²
0-3 km storm-relative helicity
106 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

427 
WUUS51 KCTP 151854
SVRCTP
PAC035-081-097-119-151930-
/O.NEW.KCTP.SV.W.0276.210915T1854Z-210915T1930Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service State College PA
254 PM EDT Wed Sep 15 2021

The National Weather Service in State College PA has issued a

* Severe Thunderstorm Warning for...
  Northwestern Northumberland County in central Pennsylvania...
  South central Lycoming County in north central Pennsylvania...
  Northeastern Union County in central Pennsylvania...
  Southeastern Clinton County in north central Pennsylvania...

* Until 330 PM EDT.

* At 253 PM EDT, a severe thunderstorm was located over Carroll,
  moving east at 40 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* Locations impacted include...
  Milton, Montoursville, Carroll, Muncy, Watsontown, Montgomery, New
  Columbia, Allenwood, Elimsport, Spruce Run Reservoir, Delaware Run,
  R.B. Winter State Park, West Milton, Turbotville, Loganton and
  McEwensville.

For those driving on Interstate 80, this includes areas between the
Loganton and Danville exits, specifically from mile markers 185 to
216.

This includes Interstate 180 from mile markers 1 to 18.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4117 7672 4117 7673 4107 7674 4105 7676
      4100 7678 4099 7720 4104 7715 4100 7730
      4107 7733 4127 7681
TIME...MOT...LOC 1853Z 249DEG 34KT 4104 7720 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Evanego
1 follow-up statement
914 
WWUS51 KCTP 151915
SVSCTP

Severe Weather Statement
National Weather Service State College PA
315 PM EDT Wed Sep 15 2021

PAC035-151924-
/O.CAN.KCTP.SV.W.0276.000000T0000Z-210915T1930Z/
Clinton PA-
315 PM EDT Wed Sep 15 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN CLINTON COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 800 PM EDT for
central and north central Pennsylvania.

LAT...LON 4099 7710 4106 7706 4114 7710 4125 7680
      4117 7672 4117 7673 4107 7674 4105 7676
      4100 7678
TIME...MOT...LOC 1914Z 251DEG 31KT 4108 7699 

$$

PAC081-097-119-151930-
/O.CON.KCTP.SV.W.0276.000000T0000Z-210915T1930Z/
Northumberland PA-Lycoming PA-Union PA-
315 PM EDT Wed Sep 15 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 PM EDT
FOR NORTHWESTERN NORTHUMBERLAND...SOUTH CENTRAL LYCOMING AND
NORTHEASTERN UNION COUNTIES...

At 314 PM EDT, a severe thunderstorm was located near Spruce Run
Reservoir, moving east at 35 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

Locations impacted include...
Milton, Muncy, Watsontown, Montgomery, New Columbia, Allenwood,
Elimsport, Delaware Run, Spruce Run Reservoir, West Milton,
Turbotville and McEwensville.

For those driving on Interstate 80, this includes areas between the
Mile Run and Danville exits, specifically from mile markers 200 to
216.

This includes Interstate 180 from mile markers 1 to 15.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4099 7710 4106 7706 4114 7710 4125 7680
      4117 7672 4117 7673 4107 7674 4105 7676
      4100 7678
TIME...MOT...LOC 1914Z 251DEG 31KT 4108 7699 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Banghoff

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 15, 11:48 AM EDTSpecial Weather StatementCTPWarren42 min
Sep 15, 1:11 PM EDTSpecial Weather StatementCTPSullivan49 min
Sep 15, 1:27 PM EDTSpecial Weather StatementCTPCentre33 min
Sep 15, 1:44 PM EDTSevere Thunderstorm WarningCTPCentre31 min
Sep 15, 1:48 PM EDTSevere Thunderstorm WarningCTPSullivan42 min
Sep 15, 2:14 PM EDTAreal Flood AdvisoryCTPLycoming, Sullivan2 hr
Sep 15, 2:14 PM EDTSevere Thunderstorm WarningCTPCentre, Clinton31 min
Sep 15, 2:36 PM EDTFlash Flood WarningCTPLycoming, Sullivan66 min
Sep 15, 2:45 PM EDTSpecial Weather StatementCTPUnion30 min
Sep 15, 2:46 PM EDTSpecial Weather StatementCTPSullivan44 min
Sep 15, 3:13 PM EDTSpecial Weather StatementCTPUnion17 min
Sep 15, 3:20 PM EDTSevere Thunderstorm WarningCTPJuniata, Mifflin40 min
Sep 15, 3:24 PM EDTSevere Thunderstorm WarningCTPMontour, Northumberland, Union36 min
Sep 15, 3:30 PM EDTSpecial Weather StatementCTPHuntingdon30 min
Sep 15, 3:55 PM EDTSpecial Weather StatementCTPSnyder35 min
Sep 15, 3:59 PM EDTSpecial Weather StatementCTPColumbia, Montour31 min
Sep 15, 4:03 PM EDTAreal Flood AdvisoryCTPLycoming, Sullivan2 hr
Sep 15, 4:12 PM EDTFlash Flood WarningCTPColumbia, Lycoming, Sullivan3 hr
Sep 15, 4:18 PM EDTSevere Thunderstorm WarningCTPColumbia27 min
Sep 15, 4:27 PM EDTSpecial Weather StatementCTPPerry33 min
Sep 15, 4:36 PM EDTSpecial Weather StatementCTPColumbia, Northumberland24 min
Sep 15, 4:43 PM EDTSevere Thunderstorm WarningCTPCumberland, Franklin, Perry32 min
Sep 15, 4:46 PM EDTAreal Flood AdvisoryCTPMontour, Northumberland89 min
Sep 15, 4:58 PM EDTSpecial Weather StatementCTPNorthumberland32 min
Sep 15, 4:59 PM EDTSpecial Weather StatementCTPPerry31 min
Sep 15, 5:15 PM EDTSpecial Weather StatementCTPPerry30 min
Sep 15, 5:19 PM EDTSpecial Weather StatementCTPFranklin26 min
Sep 15, 5:32 PM EDTSpecial Weather StatementCTPDauphin28 min
Sep 15, 5:37 PM EDTSpecial Weather StatementCTPSchuylkill23 min
Sep 15, 5:54 PM EDTSpecial Weather StatementCTPLebanon36 min
Sep 15, 6:16 PM EDTSpecial Weather StatementCTPYork29 min
Sep 15, 6:17 PM EDTSevere Thunderstorm WarningCTPLebanon, Schuylkill43 min
Sep 15, 6:24 PM EDTSevere Thunderstorm WarningCTPAdams, Franklin27 min
Sep 15, 6:41 PM EDTSpecial Weather StatementCTPDauphin34 min
Sep 15, 6:54 PM EDTSpecial Weather StatementCTPBerks21 min
Sep 15, 7:09 PM EDTAreal Flood AdvisoryCTPDauphin, York96 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2021Every severe thunderstorm warning in 2021

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.