Alert archive / New Jersey / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 248, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 10, 2021, 8:36 PM EDT for 6 counties in New Jersey; 4 counties in Pennsylvania. It was in force for 39 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 10, 2021, 8:36 PM EDT (00:36 UTC)
- Expired
- Aug 10, 2021, 9:15 PM EDT
- In force
- 39 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Atlantic County, NJ, Burlington County, NJ, Camden County, NJ, Cumberland County, NJ, Gloucester County, NJ, Salem County, NJ, Bucks County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA
The radar
The Philadelphia radar (KDIX), 63 km from the middle of the area, began a volume at 00:36 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 10, 8:44 PM EDT | TSTM WND DMG | 2 Nnw Stow Creek Twp, NJ | WIRES DOWN NEAR GRAVELY HILL RD. 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
Wallops Is Stn, VA (KWAL), launched 00:00Z, 0.6 hours before the alert went out and 194 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
- 476 J/kg
- Mixed-layer CIN
- -99 J/kg
- Mixed-layer LCL
- 1128 m above ground
- 0-6 km bulk shear
- 22 kt
- 0-1 km storm-relative helicity
- 118 m²/s²
- 0-3 km storm-relative helicity
- 120 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
477
WUUS51 KPHI 110036
SVRPHI
NJC001-005-007-011-015-033-PAC017-045-091-101-110115-
/O.NEW.KPHI.SV.W.0248.210811T0036Z-210811T0115Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
836 PM EDT Tue Aug 10 2021
The National Weather Service in Mount Holly NJ has issued a
* Severe Thunderstorm Warning for...
Northwestern Atlantic County in southern New Jersey...
Central Cumberland County in southern New Jersey...
Central Salem County in southern New Jersey...
Camden County in southern New Jersey...
Gloucester County in southern New Jersey...
Northwestern Burlington County in southern New Jersey...
Southeastern Montgomery County in southeastern Pennsylvania...
Southeastern Bucks County in southeastern Pennsylvania...
Philadelphia County in southeastern Pennsylvania...
Southeastern Delaware County in southeastern Pennsylvania...
* Until 915 PM EDT.
* At 836 PM EDT, severe thunderstorms were located along a line
extending from Germantown to near Quinton, moving southeast at 35
mph.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Damage to roofs, siding, trees, and power lines is
possible.
* Locations impacted include...
Philadelphia, Camden, Vineland, Millville, Bridgeton, Gloucester
City, Cumberland, Cherry Hill, Bensalem, Evesham, Mount Laurel,
Willingboro, Deptford, Voorhees, Medford, West Deptford, Glassboro,
Lindenwold, Hammonton and Lumberton.
This includes the following highways...
New Jersey Turnpike between exits 2 and 7A.
Pennsylvania Turnpike between mile markers 353 and 359.
Interstate 95 in Pennsylvania between mile markers 8 and 40.
Interstate 76 in Pennsylvania between mile markers 336 and 351.
Interstate 76 in New Jersey between mile markers 0 and 3.
Interstate 295 in New Jersey between mile markers 12 and 56.
Interstate 676 in Pennsylvania between mile markers 0 and 1.
Interstate 676 in New Jersey between mile markers 0 and 4.
Atlantic City Expressway between mile markers 28 and 44.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 3925 7498 3951 7542 4012 7525 4014 7461
TIME...MOT...LOC 0036Z 302DEG 28KT 4005 7521 3958 7539
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
SFJ2 follow-up statements
503
WWUS51 KPHI 110058
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
858 PM EDT Tue Aug 10 2021
NJC001-005-007-011-015-033-PAC017-045-091-101-110115-
/O.CON.KPHI.SV.W.0248.000000T0000Z-210811T0115Z/
Atlantic NJ-Cumberland NJ-Salem NJ-Camden NJ-Gloucester NJ-
Burlington NJ-Montgomery PA-Bucks PA-Philadelphia PA-Delaware PA-
858 PM EDT Tue Aug 10 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM EDT
FOR NORTHWESTERN ATLANTIC...CENTRAL CUMBERLAND...CENTRAL SALEM...
CAMDEN...GLOUCESTER...NORTHWESTERN BURLINGTON...SOUTHEASTERN
MONTGOMERY...SOUTHEASTERN BUCKS...PHILADELPHIA AND SOUTHEASTERN
DELAWARE COUNTIES...
At 857 PM EDT, severe thunderstorms were located along a line
extending from Cherry Hill Mall to Seabrook Farms, moving southeast
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...
Philadelphia, Camden, Vineland, Millville, Bridgeton, Gloucester
City, Cumberland, Cherry Hill, Bensalem, Evesham, Mount Laurel,
Willingboro, Deptford, Voorhees, Medford, West Deptford, Glassboro,
Lindenwold, Hammonton and Lumberton.
This includes the following highways...
New Jersey Turnpike between exits 2 and 7A.
Pennsylvania Turnpike between mile markers 353 and 359.
Interstate 95 in Pennsylvania between mile markers 8 and 40.
Interstate 76 in Pennsylvania between mile markers 336 and 351.
Interstate 76 in New Jersey between mile markers 0 and 3.
Interstate 295 in New Jersey between mile markers 12 and 56.
Interstate 676 in Pennsylvania between mile markers 0 and 1.
Interstate 676 in New Jersey between mile markers 0 and 4.
Atlantic City Expressway between mile markers 28 and 44.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 3925 7498 3951 7542 4012 7525 4014 7461
TIME...MOT...LOC 0057Z 302DEG 28KT 3996 7503 3949 7521
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
SFJ331
WWUS51 KPHI 110106
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
906 PM EDT Tue Aug 10 2021
NJC001-005-007-011-015-033-PAC017-045-091-101-110116-
/O.EXP.KPHI.SV.W.0248.000000T0000Z-210811T0115Z/
Atlantic NJ-Cumberland NJ-Salem NJ-Camden NJ-Gloucester NJ-
Burlington NJ-Montgomery PA-Bucks PA-Philadelphia PA-Delaware PA-
906 PM EDT Tue Aug 10 2021
...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN ATLANTIC...
CENTRAL CUMBERLAND...CENTRAL SALEM...CAMDEN...GLOUCESTER...
NORTHWESTERN BURLINGTON...SOUTHEASTERN MONTGOMERY...SOUTHEASTERN
BUCKS...PHILADELPHIA AND SOUTHEASTERN DELAWARE COUNTIES WILL EXPIRE
AT 915 PM EDT...
The storms which prompted the warning have weakened below severe
limits, and no longer pose an immediate threat to life or property.
Therefore, the warning will be allowed to expire. However gusty
winds to 40 mph are still possible with these thunderstorms.
LAT...LON 3925 7498 3951 7542 4012 7525 4014 7461
TIME...MOT...LOC 0106Z 302DEG 28KT 3993 7497 3946 7515
$$
SFJThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 10, 8:02 PM EDT | Severe Thunderstorm Warning | PHI | Camden, Gloucester | 43 min |
| Aug 10, 8:18 PM EDT | Severe Thunderstorm Warning | PHI | Gloucester, Salem | 42 min |
| Aug 10, 8:23 PM EDT | Special Marine Warning | PHI | 79 min | |
| Aug 10, 8:43 PM EDT | Areal Flood Advisory | PHI | Burlington, Camden, Gloucester | 2 hr |
| Aug 10, 9:07 PM EDT | Special Weather Statement | PHI | Burlington, Camden, Cumberland | 23 min |
| Aug 11, 2:56 PM EDT | Excessive Heat Watch | PHI | Hunterdon, Morris, Warren | 12 hr |
| Aug 11, 5:57 PM EDT | Special Weather Statement | PHI | Sussex | 48 min |
| Aug 11, 6:32 PM EDT | Special Weather Statement | PHI | Morris, Sussex, Warren | 28 min |
| Aug 11, 6:50 PM EDT | Areal Flood Advisory | PHI | Hunterdon, Morris, Somerset, Sussex, Warren | 3 hr |
| Aug 11, 7:04 PM EDT | Areal Flood Advisory | PHI | Gloucester, Hunterdon, Salem | 2 hr |
| Aug 11, 7:04 PM EDT | Severe Thunderstorm Warning | PHI | Morris, Sussex, Warren | 41 min |
| Aug 11, 7:11 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Camden, Gloucester | 49 min |
| Aug 11, 7:28 PM EDT | Flash Flood Warning | PHI | Morris, Warren | 3 hr |
| Aug 11, 7:45 PM EDT | Special Weather Statement | PHI | Morris | 45 min |
| Aug 11, 7:52 PM EDT | Special Weather Statement | PHI | Atlantic, Burlington, Camden, Gloucester, Mercer | 53 min |
| Aug 11, 7:57 PM EDT | Special Weather Statement | PHI | Hunterdon, Middlesex, Somerset | 48 min |
| Aug 11, 4:46 PM EDT | Special Weather Statement | PHI | Monroe | 44 min |
| Aug 11, 4:58 PM EDT | Special Weather Statement | PHI | Berks | 47 min |
| Aug 11, 5:20 PM EDT | Areal Flood Advisory | PHI | Carbon, Monroe | 57 min |
| Aug 11, 5:48 PM EDT | Severe Thunderstorm Warning | PHI | Berks | 57 min |
| Aug 11, 6:16 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Lehigh, Montgomery | 44 min |
| Aug 11, 6:26 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Chester, Delaware, Montgomery | 49 min |
| Aug 11, 6:48 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Lehigh, Montgomery, Northampton | 42 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.