Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2020
Severe Thunderstorm Warning 230, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 12, 2020, 1:54 PM EDT for New Castle County, Delaware; Burlington County, Camden County, Gloucester County, New Jersey; 4 counties in Pennsylvania. It was in force for 51 min. 14 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
- Aug 12, 2020, 1:54 PM EDT (17:54 UTC)
- Expired
- Aug 12, 2020, 2:45 PM EDT
- In force
- 51 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties New Castle County, DE, Burlington County, NJ, Camden County, NJ, Gloucester County, NJ, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA
The radar
The Philadelphia radar (KDIX), 84 km from the middle of the area, began a volume at 17:56 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, 1:54 PM EDT | TSTM WND DMG | 1 Nw Willistown Twp, PA | LARGE TREE LIMBS ON DUTTON MILL ROAD NEAR CRATIN LANE. TIME ESTIMATED FROM RADAR. |
| Aug 12, 1:54 PM EDT | TSTM WND DMG | 2 N Winterthur, DE | SEVERAL TREES DOWN ON TWADDELL MILL ROAD. TIME ESTIMATED FROM RADAR. |
| Aug 12, 2:00 PM EDT | TSTM WND GST 60 | 2 Sse East Goshen Twp., PA | WITH STREET FLOODING AND SEVERAL DOWNED TREES AND POWER LINES. TIME ESTIMATED FROM RADAR. |
| Aug 12, 2:00 PM EDT | HAIL 0.25 | 2 E West Goshen, PA | TIME ESTIMATED FROM RADAR. |
| Aug 12, 2:01 PM EDT | TSTM WND DMG | Greenville, DE | REPORTS OF TREES AND WIRES DOWN IN GREENVILLE. TIME ESTIMATED FROM RADAR. |
| Aug 12, 2:04 PM EDT | TSTM WND DMG | Edenridge, DE | REPORTS OF DOWNED TREE LIMBS AND WIRES NEAR KILBURN ROAD AND MOUNT LEBANON ROAD. STREET FLOODING ALSO REPORTED. TIME ESTIMATED FROM RADAR. |
| Aug 12, 2:19 PM EDT | TSTM WND DMG | Haddon Heights, NJ | POWER LINES DOWN IN HADDON HEIGHTS. TIME ESTIMATED FROM RADAR. |
| Aug 12, 2:30 PM EDT | TSTM WND DMG | East Caln Twp, PA | TREES AND WIRES DOWN NEAR COUNTRY CLUB DR AT E LANCASTER AVE, NEAR THE DOWNINGTOWN COUNTRY CLUB. TIME ESTIMATED FROM RADAR. |
| Aug 12, 2:31 PM EDT | TSTM WND DMG | 2 Se East Caln Twp, PA | TREE DOWN PARTIALLY BLOCKING BOOT RD NEAR CIRCLE DR. TIME ESTIMATED FROM RADAR. |
| Aug 12, 2:33 PM EDT | TSTM WND DMG | 1 Wnw Woodbury, NJ | DOWNED TREE LIMBS AND WIRES NEAR GIRARD STREET IN WOODBURY. TIME ESTIMATED FROM RADAR. |
| Aug 12, 2:35 PM EDT | TSTM WND DMG | Woodbury, NJ | SEVERAL REPORTS OF TREE LIMBS AND WIRES DOWN IN WEST DEPTFORD AND WOODBURY. TIME ESTIMATED FROM RADAR. |
| Aug 12, 2:35 PM EDT | TSTM WND DMG | Woodbury, NJ | DOWNED TREE LIMBS AND WIRES NEAR WEST STREET AND GLOVER STREET IN WOODBURY. TIME ESTIMATED FROM RADAR. |
| Aug 12, 2:38 PM EDT | TSTM WND DMG | Woodbury Heights, NJ | DOWNED TREE LIMBS AND WIRES NEAR THE LAKE AVENUE AND PARK AVENUE INTERSECTION IN WOODBURY HEIGHTS. TIME ESTIMATED FROM RADAR. |
| Aug 12, 2:54 PM EDT | TSTM WND DMG | 1 N Blackwood, NJ | DOWNED TREE LIMBS AND POWER LINES NEAR KEYSTONE AVENUE IN BLACKWOOD. 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
Washington/Dulle, VA (KIAD), launched 12:00Z, 5.9 hours before the alert went out and 200 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
- 127 J/kg
- Mixed-layer CIN
- -149 J/kg
- Mixed-layer LCL
- 1202 m above ground
- 0-6 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- 0 m²/s²
- 0-3 km storm-relative helicity
- 48 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
009
WUUS51 KPHI 121754
SVRPHI
DEC003-NJC005-007-015-PAC029-045-091-101-121845-
/O.NEW.KPHI.SV.W.0230.200812T1754Z-200812T1845Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
154 PM EDT Wed Aug 12 2020
The National Weather Service in Mount Holly NJ has issued a
* Severe Thunderstorm Warning for...
Northern New Castle County in northern Delaware...
Northwestern Camden County in southern New Jersey...
Northwestern Gloucester County in southern New Jersey...
West central Burlington County in southern New Jersey...
Southeastern Montgomery County in southeastern Pennsylvania...
Southeastern Chester County in southeastern Pennsylvania...
Southwestern Philadelphia County in southeastern Pennsylvania...
Delaware County in southeastern Pennsylvania...
* Until 245 PM EDT.
* At 153 PM EDT, severe thunderstorms were located along a line
extending from Evesham to Westtown, moving southwest at 10 mph.
HAZARD...60 mph wind gusts.
SOURCE...Law enforcement. These storms have downed several power
lines in Burlington County.
IMPACT...Damage to roofs, siding, trees, and power lines is
possible.
* Locations impacted include...
Philadelphia, Camden, Wilmington, West Chester, Gloucester City,
Cherry Hill, Evesham, Mount Laurel, Chester, Deptford, Voorhees,
Medford, West Deptford, Lindenwold, Bellmawr, Yeadon, Westtown,
Woodbury, Downingtown and Berlin.
This includes the following highways...
New Jersey Turnpike between exits 3 and 4.
Interstate 95 in Pennsylvania between mile markers 0 and 25.
Interstate 95 in Delaware between mile markers 15 and 23.
Interstate 76 in Pennsylvania between mile markers 341 and 351.
Interstate 76 in New Jersey between mile markers 0 and 3.
Interstate 295 in New Jersey between mile markers 11 and 40.
Interstate 676 in Pennsylvania between mile markers 0 and 1.
Interstate 676 in New Jersey between mile markers 0 and 4.
Interstate 476 in Pennsylvania between mile markers 0 and 12.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Protecting yourself from immediate threats to life and safety shall
take priority. Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.
For your protection move to an interior room on the lowest floor of a
building.
In addition to large hail and damaging winds, frequent cloud to
ground lightning is occurring with these storms. Move indoors
immediately. Remember, if you can hear thunder, you are close enough
to be struck by lightning.
Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4007 7569 3994 7476 3980 7490 3976 7540
3978 7541 3978 7544 3976 7546 3974 7573
TIME...MOT...LOC 1753Z 036DEG 7KT 3988 7490 3991 7555
HAIL...<.75IN
WIND...60MPH
$$
CMS1 follow-up statement
263
WWUS51 KPHI 121816
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
216 PM EDT Wed Aug 12 2020
DEC003-NJC005-007-015-PAC029-045-091-101-121845-
/O.CON.KPHI.SV.W.0230.000000T0000Z-200812T1845Z/
New Castle DE-Camden NJ-Gloucester NJ-Burlington NJ-Montgomery PA-
Chester PA-Philadelphia PA-Delaware PA-
216 PM EDT Wed Aug 12 2020
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 245 PM EDT
FOR NORTHERN NEW CASTLE...NORTHWESTERN CAMDEN...NORTHWESTERN
GLOUCESTER...WEST CENTRAL BURLINGTON...SOUTHEASTERN MONTGOMERY...
SOUTHEASTERN CHESTER...SOUTHWESTERN PHILADELPHIA AND DELAWARE
COUNTIES...
At 216 PM EDT, severe thunderstorms were located along a line
extending from Voorhees to Elam, moving south at 10 mph.
HAZARD...60 mph wind gusts.
SOURCE...Law enforcement. This storm downed trees in West Goshen
Township in Chester County.
IMPACT...Damage to roofs, siding, trees, and power lines is
possible.
Locations impacted include...
Philadelphia, Camden, Wilmington, West Chester, Gloucester City,
Cherry Hill, Evesham, Mount Laurel, Chester, Deptford, Voorhees,
Medford, West Deptford, Lindenwold, Bellmawr, Yeadon, Westtown,
Woodbury, Downingtown and Berlin.
This includes the following highways...
New Jersey Turnpike between exits 3 and 4.
Interstate 95 in Pennsylvania between mile markers 0 and 25.
Interstate 95 in Delaware between mile markers 15 and 23.
Interstate 76 in Pennsylvania between mile markers 341 and 351.
Interstate 76 in New Jersey between mile markers 0 and 3.
Interstate 295 in New Jersey between mile markers 11 and 40.
Interstate 676 in Pennsylvania between mile markers 0 and 1.
Interstate 676 in New Jersey between mile markers 0 and 4.
Interstate 476 in Pennsylvania between mile markers 0 and 12.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Protecting yourself from immediate threats to life and safety shall
take priority. Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.
For your protection move to an interior room on the lowest floor of a
building.
Frequent cloud to ground lightning is occurring with these storms.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.
Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4007 7569 3994 7476 3980 7490 3976 7540
3978 7541 3978 7544 3976 7546 3974 7573
TIME...MOT...LOC 1816Z 006DEG 8KT 3985 7493 3984 7552
HAIL...<.75IN
WIND...60MPH
$$
CMSThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 12, 12:43 PM EDT | Areal Flood Advisory | PHI | New Castle | 3 hr |
| Aug 12, 12:55 PM EDT | Areal Flood Advisory | PHI | Kent, New Castle | 3 hr |
| Aug 12, 12:55 PM EDT | Special Weather Statement | PHI | Kent | 35 min |
| Aug 12, 1:06 PM EDT | Flash Flood Warning | PHI | Kent, New Castle | 3 hr |
| Aug 12, 1:37 PM EDT | Areal Flood Advisory | PHI | New Castle | 3 hr |
| Aug 12, 2:38 PM EDT | Severe Thunderstorm Warning | PHI | Kent | 52 min |
| Aug 12, 2:40 PM EDT | Flash Flood Warning | PHI | New Castle | 3 hr |
| Aug 12, 3:06 PM EDT | Areal Flood Advisory | PHI | Kent, Sussex | 3 hr |
| Aug 12, 3:15 PM EDT | Severe Thunderstorm Warning | PHI | Kent, Sussex | 45 min |
| Aug 12, 3:20 PM EDT | Severe Thunderstorm Warning | PHI | New Castle | 29 min |
| Aug 12, 3:31 PM EDT | Flash Flood Warning | PHI | Kent | 3 hr |
| Aug 12, 3:46 PM EDT | Flash Flood Warning | PHI | Kent, Sussex | 3 hr |
| Aug 12, 4:00 PM EDT | Special Weather Statement | PHI | Kent | 30 min |
| Aug 12, 12:06 PM EDT | Special Weather Statement | PHI | Monmouth | 24 min |
| Aug 12, 12:16 PM EDT | Special Weather Statement | PHI | Burlington | 29 min |
| Aug 12, 12:33 PM EDT | Severe Thunderstorm Warning | PHI | Burlington | 42 min |
| Aug 12, 12:45 PM EDT | Severe Thunderstorm Warning | PHI | Monmouth, Ocean | 45 min |
| Aug 12, 1:12 PM EDT | Flash Flood Warning | PHI | Burlington | 3 hr |
| Aug 12, 1:12 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Camden, Gloucester, Monmouth, Ocean | 48 min |
| Aug 12, 1:25 PM EDT | Severe Thunderstorm Warning | PHI | Monmouth, Ocean | 50 min |
| Aug 12, 1:57 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Burlington, Ocean | 48 min |
| Aug 12, 2:42 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Ocean | 25 min |
| Aug 12, 2:44 PM EDT | Severe Thunderstorm Warning | PHI | Camden, Gloucester | 46 min |
| Aug 12, 3:12 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Burlington, Camden, Gloucester, Salem | 29 min |
| Aug 12, 3:54 PM EDT | Special Marine Warning | PHI | 53 min | |
| Aug 12, 11:48 AM EDT | Special Weather Statement | PHI | Philadelphia | 27 min |
| Aug 12, 1:47 PM EDT | Flash Flood Warning | PHI | Chester, Delaware | 2 hr |
| Aug 12, 2:04 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Montgomery, Philadelphia | 21 min |
| Aug 12, 3:36 PM EDT | Flash Flood Warning | PHI | Chester | 108 min |
| Aug 12, 5:04 PM EDT | Areal Flood Advisory | PHI | Lehigh, Northampton | 56 min |
| Aug 12, 5:09 PM EDT | Areal Flood Warning | PHI | Berks | 51 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 2020Severe Thunderstorm Warnings in New Jersey, 2020Severe Thunderstorm Warnings in Delaware, 2020Every severe thunderstorm warning in 2020
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.