Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 257, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 12, 2021, 3:33 PM EDT for Monroe County, Northampton County, Pennsylvania; Sussex County, Warren County, New Jersey. It was in force for 57 min. 1 report came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- Aug 12, 2021, 3:33 PM EDT (19:33 UTC)
- Expired
- Aug 12, 2021, 4:30 PM EDT
- In force
- 57 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Sussex County, NJ, Warren County, NJ, Monroe County, PA, Northampton County, PA
The radar
The Philadelphia radar (KDIX), 140 km from the middle of the area, began a volume at 19:36 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Aug 12, 3:55 PM EDT | TSTM WND DMG | Five Points, NJ | MULTIPLE REPORTS OF TREES AND WIRES DOWN IN SUSSEX COUNTY. TIME ESTIMATED FROM RADAR. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Brookhaven, NY (KOKX), launched 12:00Z, 7.6 hours before the alert went out and 175 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.
- Mixed-layer CAPE
- 278 J/kg
- Mixed-layer CIN
- -162 J/kg
- Mixed-layer LCL
- 1400 m above ground
- 0-6 km bulk shear
- 14 kt
- 0-1 km storm-relative helicity
- -82 m²/s²
- 0-3 km storm-relative helicity
- -47 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
903
WUUS51 KPHI 121933
SVRPHI
NJC037-041-PAC089-095-122030-
/O.NEW.KPHI.SV.W.0257.210812T1933Z-210812T2030Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
333 PM EDT Thu Aug 12 2021
The National Weather Service in Mount Holly NJ has issued a
* Severe Thunderstorm Warning for...
Sussex County in northwestern New Jersey...
Northern Warren County in northwestern New Jersey...
Eastern Monroe County in northeastern Pennsylvania...
Northeastern Northampton County in eastern Pennsylvania...
* Until 430 PM EDT.
* At 333 PM EDT, severe thunderstorms were located along a line
extending from Ledgerdale to near Canadensis to McMichael, moving
east at 50 mph.
HAZARD...60 mph wind gusts.
SOURCE...Law enforcement. At around 3:25 PM, downed trees were
reported in Tobyhanna. These storms have a history of
producing wind damage.
IMPACT...Damage to roofs, siding, trees, and power lines is
possible.
* Locations impacted include...
Newton, Montague, Hopatcong, East Stroudsburg, Blairstown,
Franklin, Stanhope, Hamburg, Ogdensburg, Sussex, Hope, Branchville,
Andover, Stormville, High Point, Henryville, Lake Mohawk, Werry
Lake, Greendell and Millbrook.
People at the New Jersey State Fair should seek safe shelter
immediately!
This includes the following highways...
Interstate 80 in Pennsylvania between mile markers 306 and 314.
Interstate 80 in New Jersey between mile markers 0 and 24.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Wind damage with these storms will occur before any rain or
lightning. Do not wait for the sound of thunder before taking cover.
SEEK SHELTER IMMEDIATELY inside a sturdy structure and stay away from
windows.
&&
LAT...LON 4120 7437 4097 7464 4092 7466 4088 7498
4092 7531 4114 7525 4123 7520 4125 7522
4125 7513 4115 7515 4114 7509 4108 7503
4116 7490 4127 7484 4135 7475 4136 7469
TIME...MOT...LOC 1933Z 254DEG 45KT 4137 7531 4117 7519 4100 7541
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...OBSERVED
MAX WIND GUST...60 MPH
$$
JEO3 follow-up statements
348
WWUS51 KPHI 122001
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
401 PM EDT Thu Aug 12 2021
NJC037-041-PAC089-095-122030-
/O.CON.KPHI.SV.W.0257.000000T0000Z-210812T2030Z/
Sussex NJ-Warren NJ-Monroe PA-Northampton PA-
401 PM EDT Thu Aug 12 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 430 PM EDT
FOR SUSSEX...NORTHERN WARREN...EAST CENTRAL MONROE AND NORTHEASTERN
NORTHAMPTON COUNTIES...
At 359 PM EDT, severe thunderstorms were located along a line
extending from Shohola to Hainesville to Bushkill, moving east at 50
mph.
HAZARD...60 mph wind gusts.
SOURCE...Law enforcement.
IMPACT...Damage to roofs, siding, trees, and power lines is
possible.
Locations impacted include...
Newton, Montague, Hopatcong, Blairstown, Franklin, Stanhope, Hamburg,
Ogdensburg, Sussex, Hope, Branchville, Andover, High Point, Lake
Mohawk, Werry Lake, Greendell, Millbrook, Delaware Water Gap, Vernon
Valley and Pellettown.
People at the New Jersey State Fair should seek safe shelter
immediately!
This includes the following highways...
Interstate 80 in Pennsylvania near mile marker 314.
Interstate 80 in New Jersey between mile markers 0 and 24.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Wind damage with these storms will occur before any rain or
lightning. Do not wait for the sound of thunder before taking cover.
SEEK SHELTER IMMEDIATELY inside a sturdy structure and stay away from
windows.
&&
LAT...LON 4120 7437 4097 7464 4092 7466 4088 7498
4090 7517 4110 7512 4110 7505 4108 7503
4116 7490 4127 7484 4135 7475 4136 7469
TIME...MOT...LOC 1959Z 254DEG 45KT 4145 7492 4125 7480 4108 7502
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...OBSERVED
MAX WIND GUST...60 MPH
$$
JEO961
WWUS51 KPHI 122014
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
414 PM EDT Thu Aug 12 2021
PAC089-095-122024-
/O.CAN.KPHI.SV.W.0257.000000T0000Z-210812T2030Z/
Monroe PA-Northampton PA-
414 PM EDT Thu Aug 12 2021
...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL MONROE AND
NORTHEASTERN NORTHAMPTON COUNTIES IS CANCELLED...
The storms which prompted the warning have moved out of the warned
area. Therefore, the warning has been cancelled.
LAT...LON 4120 7437 4097 7464 4092 7466 4088 7498
4089 7504 4104 7500 4105 7494 4113 7481
4127 7484 4132 7472 4134 7465
TIME...MOT...LOC 2014Z 254DEG 45KT 4149 7472 4129 7460 4112 7482
$$
NJC037-041-122030-
/O.CON.KPHI.SV.W.0257.000000T0000Z-210812T2030Z/
Sussex NJ-Warren NJ-
414 PM EDT Thu Aug 12 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 430 PM EDT
FOR SUSSEX AND NORTHEASTERN WARREN COUNTIES...
At 414 PM EDT, severe thunderstorms were located along a line
extending from near Oakland to Unionville to Crandon Lakes, moving
east at 50 mph.
HAZARD...60 mph wind gusts.
SOURCE...Law enforcement. These storms have a history of producing
downed trees and power lines.
IMPACT...Damage to roofs, siding, trees, and power lines is
possible.
Locations impacted include...
Newton, Hopatcong, Blairstown, Franklin, Stanhope, Hamburg,
Ogdensburg, Sussex, Hope, Branchville, Andover, Allamuchy-Panther
Valley, High Point, Lake Mohawk, Greendell, Vernon Valley, Five
Points, Pellettown, Highland Lake and Hainesville.
People at the New Jersey State Fair should seek safe shelter
immediately!
This includes Interstate 80 in New Jersey between mile markers 9 and
24.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Wind damage with these storms will occur before any rain or
lightning. Do not wait for the sound of thunder before taking cover.
SEEK SHELTER IMMEDIATELY inside a sturdy structure and stay away from
windows.
&&
LAT...LON 4120 7437 4097 7464 4092 7466 4088 7498
4089 7504 4104 7500 4105 7494 4113 7481
4127 7484 4132 7472 4134 7465
TIME...MOT...LOC 2014Z 254DEG 45KT 4149 7472 4129 7460 4112 7482
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...OBSERVED
MAX WIND GUST...60 MPH
$$
JEO527
WWUS51 KPHI 122029
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
429 PM EDT Thu Aug 12 2021
NJC037-041-122037-
/O.EXP.KPHI.SV.W.0257.000000T0000Z-210812T2030Z/
Sussex NJ-Warren NJ-
429 PM EDT Thu Aug 12 2021
...THE SEVERE THUNDERSTORM WARNING FOR SUSSEX AND NORTHEASTERN WARREN
COUNTIES WILL EXPIRE AT 430 PM EDT...
The storms which prompted the warning have moved out of the area.
Therefore, the warning will be allowed to expire.
LAT...LON 4120 7437 4097 7464 4092 7466 4088 7498
4089 7504 4104 7500 4105 7494 4113 7481
4127 7484 4132 7472 4134 7465
TIME...MOT...LOC 2027Z 254DEG 45KT 4149 7472 4129 7460 4112 7482
$$
JEOThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 12, 2:56 PM EDT | Severe Thunderstorm Warning | PHI | Carbon, Monroe | 49 min |
| Aug 12, 3:38 PM EDT | Special Weather Statement | PHI | Carbon | 52 min |
| Aug 11, 8:10 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Morris, Sussex, Warren | 35 min |
| Aug 11, 10:54 PM EDT | Areal Flood Warning | PHI | Morris, Warren | 3 hr |
| Aug 12, 4:11 PM EDT | Severe Thunderstorm Warning | PHI | Morris, Sussex, Warren | 34 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 2021Severe Thunderstorm Warnings in New Jersey, 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.