Alert archive / New Jersey / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 232, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 29, 2021, 5:03 PM EDT for 5 counties in New Jersey; 4 counties in Pennsylvania. It was in force for 42 min. 4 reports 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
- Jul 29, 2021, 5:03 PM EDT (21:03 UTC)
- Expired
- Jul 29, 2021, 5:45 PM EDT
- In force
- 42 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Tornado
- Possible
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Hunterdon County, NJ, Morris County, NJ, Somerset County, NJ, Sussex County, NJ, Warren County, NJ, Bucks County, PA, Lehigh County, PA, Monroe County, PA, Northampton County, PA
The radar
The Philadelphia radar (KDIX), 105 km from the middle of the area, began a volume at 21:04 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 |
|---|---|---|---|
| Jul 29, 5:11 PM EDT | TSTM WND DMG | Quakertown, PA | SEVERAL TREES DOWN, ALSO HAVE REPORTS FROM BUCKINGHAM AND UPPER MAKEFIELD. TIME ESTIMATED FROM RADAR. |
| Jul 29, 5:15 PM EDT | TSTM WND GST 53 | 1 E Milford Square, PA | QUAKERTOWN. |
| Jul 29, 5:15 PM EDT | TSTM WND GST 53 | 1 Ese Milford Square, PA | QUAKERTOWN AIRPORT AWOS MEASURED GUST. |
| Jul 29, 5:30 PM EDT | TSTM WND DMG | Ottsville, PA | DEBRIS BLOCKING FRETZ VALLEY ROAD, GEIGEL HILL ROAD AND CREAMERY ROAD. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Jul 29, 2:23 PM EDT | Tornado Watch | SPC | 8 hr |
The nearest sounding before it
Brookhaven, NY (KOKX), launched 12:00Z, 9.1 hours before the alert went out and 178 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
- 54 J/kg
- Mixed-layer CIN
- -32 J/kg
- Mixed-layer LCL
- 823 m above ground
- 0-6 km bulk shear
- 29 kt
- 0-1 km storm-relative helicity
- 65 m²/s²
- 0-3 km storm-relative helicity
- 127 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted.
151
WUUS51 KPHI 292103
SVRPHI
NJC019-027-035-037-041-PAC017-077-089-095-292145-
/O.NEW.KPHI.SV.W.0232.210729T2103Z-210729T2145Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
503 PM EDT Thu Jul 29 2021
The National Weather Service in Mount Holly NJ has issued a
* Severe Thunderstorm Warning for...
Hunterdon County in northwestern New Jersey...
Southwestern Morris County in northern New Jersey...
Southwestern Sussex County in northwestern New Jersey...
Warren County in northwestern New Jersey...
Western Somerset County in northern New Jersey...
East central Lehigh County in eastern Pennsylvania...
Northwestern Bucks County in southeastern Pennsylvania...
South central Monroe County in northeastern Pennsylvania...
Northampton County in eastern Pennsylvania...
* Until 545 PM EDT.
* At 502 PM EDT, severe thunderstorms were located along a line
extending from near Stormville to near Pleasant Valley, moving east
at 30 mph.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Damage to roofs, siding, trees, and power lines is
possible.
* Locations impacted include...
Easton, Newton, Bethlehem, Hopatcong, Forks, Hackettstown,
Quakertown, Wilson, Washington, Blairstown, Hellertown, Nazareth,
Bangor, Flemington, Tinicum, High Bridge, Stanhope, Pen Argyl,
Netcong and Wind Gap.
This includes the following highways...
Interstate 78 in Pennsylvania between mile markers 64 and 76.
Interstate 78 in New Jersey between mile markers 0 and 29.
Interstate 80 in New Jersey between mile markers 0 and 27.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A Tornado Watch remains in effect until 900 PM EDT for northern and
northwestern New Jersey...and eastern, southeastern and northeastern
Pennsylvania.
Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.
Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4106 7470 4045 7466 4042 7540 4094 7541
TIME...MOT...LOC 2102Z 255DEG 27KT 4092 7527 4047 7526
TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
$$
Fitzsimmons1 follow-up statement
313
WWUS51 KPHI 292120
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
520 PM EDT Thu Jul 29 2021
PAC077-089-292129-
/O.CAN.KPHI.SV.W.0232.000000T0000Z-210729T2145Z/
Lehigh PA-Monroe PA-
520 PM EDT Thu Jul 29 2021
...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL LEHIGH AND SOUTH
CENTRAL MONROE COUNTIES IS CANCELLED...
The storms which prompted the warning have moved out of the warned
area. Therefore, the warning has been cancelled.
A Tornado Watch remains in effect until 900 PM EDT for northern and
northwestern New Jersey...and eastern, southeastern and northeastern
Pennsylvania.
LAT...LON 4106 7470 4045 7467 4042 7537 4093 7522
4095 7515 4097 7512 4098 7513
TIME...MOT...LOC 2119Z 255DEG 27KT 4095 7511 4050 7510
$$
NJC019-027-035-037-041-PAC017-095-292145-
/O.CON.KPHI.SV.W.0232.000000T0000Z-210729T2145Z/
Hunterdon NJ-Morris NJ-Sussex NJ-Warren NJ-Somerset NJ-Bucks PA-
Northampton PA-
520 PM EDT Thu Jul 29 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 545 PM EDT
FOR HUNTERDON...SOUTHWESTERN MORRIS...SOUTHWESTERN SUSSEX...WARREN...
WESTERN SOMERSET...NORTHWESTERN BUCKS AND EASTERN NORTHAMPTON
COUNTIES...
At 519 PM EDT, severe thunderstorms were located along a line
extending from Columbia to Erwinna, moving east at 30 mph.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Damage to roofs, siding, trees, and power lines is
possible.
Locations impacted include...
Easton, Newton, Bethlehem, Forks, Hackettstown, Quakertown, Wilson,
Washington, Blairstown, Bangor, Flemington, Tinicum, High Bridge,
Stanhope, Netcong, Clinton, Belvidere, Harmony, Oxford and Alpha.
This includes the following highways...
Interstate 78 in Pennsylvania between mile markers 69 and 76.
Interstate 78 in New Jersey between mile markers 0 and 29.
Interstate 80 in New Jersey between mile markers 2 and 27.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A Tornado Watch remains in effect until 900 PM EDT for northern and
northwestern New Jersey...and eastern, southeastern and northeastern
Pennsylvania.
Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.
Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4106 7470 4045 7467 4042 7537 4093 7522
4095 7515 4097 7512 4098 7513
TIME...MOT...LOC 2119Z 255DEG 27KT 4095 7511 4050 7510
TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
$$
FitzsimmonsThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 29, 3:33 AM EDT | Small Craft Advisory | PHI | 20 hr | |
| Jul 29, 1:33 PM EDT | Special Marine Warning | PHI | 42 min | |
| Jul 29, 2:53 PM EDT | Special Marine Warning | PHI | 100 min | |
| Jul 29, 4:26 PM EDT | Special Weather Statement | PHI | Morris | 34 min |
| Jul 29, 4:30 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Warren | 45 min |
| Jul 29, 4:57 PM EDT | Areal Flood Advisory | PHI | Hunterdon, Morris, Sussex, Warren | 3 hr |
| Jul 29, 5:01 PM EDT | Special Weather Statement | PHI | Morris | 29 min |
| Jul 29, 5:08 PM EDT | Tornado Warning | PHI | Hunterdon | 37 min |
| Jul 29, 5:27 PM EDT | Areal Flood Advisory | PHI | Hunterdon, Mercer, Morris, Somerset | 3 hr |
| Jul 29, 5:32 PM EDT | Flash Flood Warning | PHI | Warren | 2 hr |
| Jul 29, 5:32 PM EDT | Tornado Warning | PHI | Hunterdon | 28 min |
| Jul 29, 5:51 PM EDT | Tornado Warning | PHI | Hunterdon, Mercer | 24 min |
| Jul 29, 5:58 PM EDT | Flash Flood Warning | PHI | Hunterdon, Mercer, Somerset | 3 hr |
| Jul 29, 6:06 PM EDT | Tornado Warning | PHI | Burlington, Hunterdon, Mercer, Middlesex, Monmouth | 39 min |
| Jul 29, 6:44 PM EDT | Tornado Warning | PHI | Mercer, Monmouth, Ocean | 46 min |
| Jul 29, 6:45 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Mercer | 45 min |
| Jul 29, 6:56 PM EDT | Flash Flood Warning | PHI | Mercer, Middlesex, Monmouth, Ocean, Somerset | 4 hr |
| Jul 29, 7:07 PM EDT | Tornado Warning | PHI | Burlington | 23 min |
| Jul 29, 7:12 PM EDT | Flash Flood Warning | PHI | Burlington | 4 hr |
| Jul 29, 7:18 PM EDT | Tornado Warning | PHI | Mercer, Middlesex, Monmouth, Ocean | 27 min |
| Jul 29, 7:25 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Monmouth, Ocean | 50 min |
| Jul 29, 7:28 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Mercer, Middlesex, Monmouth, Ocean | 47 min |
| Jul 29, 7:52 PM EDT | Special Marine Warning | PHI | 113 min | |
| Jul 29, 3:48 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Lehigh, Northampton | 42 min |
| Jul 29, 4:03 PM EDT | Tornado Warning | PHI | Berks, Lehigh, Northampton | 27 min |
| Jul 29, 4:27 PM EDT | Tornado Warning | PHI | Lehigh, Northampton | 16 min |
| Jul 29, 4:46 PM EDT | Areal Flood Advisory | PHI | Berks, Lehigh, Northampton | 3 hr |
| Jul 29, 4:56 PM EDT | Tornado Warning | PHI | Bucks, Lehigh, Northampton | 34 min |
| Jul 29, 6:21 PM EDT | Special Weather Statement | PHI | Bucks | 24 min |
Nearby
Severe Thunderstorm Warnings in New Jersey, 2021Severe 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.