Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2020
Severe Thunderstorm Warning 180, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 23, 2020, 11:44 PM EDT for 4 counties in Pennsylvania. It was in force for 46 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
- Jul 23, 2020, 11:44 PM EDT (03:44 UTC)
- Expired
- Jul 24, 2020, 12:30 AM EDT
- In force
- 46 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA
The radar
The Philadelphia radar (KDIX), 89 km from the middle of the area, began a volume at 03:46 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 nearest sounding before it
Washington/Dulle, VA (KIAD), launched 00:00Z, 3.7 hours before the alert went out and 202 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
- 229 J/kg
- Mixed-layer CIN
- -13 J/kg
- Mixed-layer LCL
- 2029 m above ground
- 0-6 km bulk shear
- 22 kt
- 0-1 km storm-relative helicity
- 10 m²/s²
- 0-3 km storm-relative helicity
- 26 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
164
WUUS51 KPHI 240344
SVRPHI
PAC029-045-091-101-240430-
/O.NEW.KPHI.SV.W.0180.200724T0344Z-200724T0430Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
1144 PM EDT Thu Jul 23 2020
The National Weather Service in Mount Holly NJ has issued a
* Severe Thunderstorm Warning for...
South central Montgomery County in southeastern Pennsylvania...
East central Chester County in southeastern Pennsylvania...
West central Philadelphia County in southeastern Pennsylvania...
Delaware County in southeastern Pennsylvania...
* Until 1230 AM EDT.
* At 1144 PM EDT, a severe thunderstorm was located over Westtown, or
over West Chester, moving northeast at 20 mph.
HAZARD...60 mph wind gusts and penny size hail.
SOURCE...Radar indicated.
IMPACT...Damage to roofs, siding, trees, and power lines is
possible.
* Locations impacted include...
Philadelphia, West Chester, Norristown, West Norriton, East
Norriton, Yeadon, Westtown, Conshohocken, Swarthmore, Narberth,
East Lansdowne, Cheyney, Morris Park, Elam, Bryn Mawr, Marshallton,
Trout Lake, Chelsea, Radnor Township and Gradyville.
This includes the following highways...
Pennsylvania Turnpike between mile markers 322 and 334.
Northeast Extension between mile markers 21 and 26.
Interstate 76 in Pennsylvania between mile markers 327 and 346.
Interstate 676 in Pennsylvania between mile markers 0 and 1.
Interstate 476 in Pennsylvania between mile markers 2 and 19.
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 this storm. Move indoors
immediately. Remember, if you can hear thunder, you are close enough
to be struck by lightning.
Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4020 7532 3995 7514 3983 7553 3984 7554
3984 7562 3995 7569
TIME...MOT...LOC 0344Z 241DEG 17KT 3993 7557
HAIL...0.75IN
WIND...60MPH
$$
Staarmann1 follow-up statement
248
WWUS51 KPHI 240408
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
1208 AM EDT Fri Jul 24 2020
PAC029-045-091-101-240430-
/O.CON.KPHI.SV.W.0180.000000T0000Z-200724T0430Z/
Montgomery PA-Chester PA-Philadelphia PA-Delaware PA-
1208 AM EDT Fri Jul 24 2020
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1230 AM EDT
FOR SOUTH CENTRAL MONTGOMERY...EAST CENTRAL CHESTER...WEST CENTRAL
PHILADELPHIA AND DELAWARE COUNTIES...
At 1208 AM EDT, a severe thunderstorm was located over Newtown
Square, or 8 miles east of West Chester, moving northeast at 20 mph.
HAZARD...60 mph wind gusts and penny size hail.
SOURCE...Radar indicated.
IMPACT...Damage to roofs, siding, trees, and power lines is
possible.
Locations impacted include...
Philadelphia, Norristown, West Norriton, East Norriton, Yeadon,
Conshohocken, Swarthmore, Narberth, East Lansdowne, Cheyney, Morris
Park, Bryn Mawr, Trout Lake, Radnor Township, Gradyville, Broomall,
Newtown Square, Roxborough, King Of Prussia and Drexel Hill.
This includes the following highways...
Pennsylvania Turnpike between mile markers 321 and 334.
Northeast Extension between mile markers 21 and 26.
Interstate 76 in Pennsylvania between mile markers 327 and 346.
Interstate 676 in Pennsylvania between mile markers 0 and 1.
Interstate 476 in Pennsylvania between mile markers 2 and 19.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Protecting yourself from immediate threats to life and safety shall
take priority. Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.
For your protection move to an interior room on the lowest floor of a
building.
Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 3987 7550 4002 7559 4020 7532 3995 7514
3988 7537
TIME...MOT...LOC 0408Z 241DEG 17KT 3997 7544
HAIL...0.75IN
WIND...60MPH
$$
StaarmannThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 23, 10:26 PM EDT | Severe Thunderstorm Warning | PHI | Chester | 49 min |
| Jul 23, 10:44 PM EDT | Areal Flood Advisory | PHI | Chester | 2 hr |
| Jul 23, 11:10 PM EDT | Areal Flood Advisory | PHI | Chester, Delaware | 2 hr |
| Jul 23, 11:16 PM EDT | Severe Thunderstorm Warning | PHI | Delaware | 44 min |
| Jul 23, 11:38 PM EDT | Special Weather Statement | PHI | Chester | 37 min |
| Jul 24, 12:24 AM EDT | Flash Flood Warning | PHI | Chester | 114 min |
| Jul 24, 12:32 AM EDT | Special Weather Statement | PHI | Bucks, Montgomery | 28 min |
| Jul 24, 12:42 AM EDT | Severe Thunderstorm Warning | PHI | Bucks, Montgomery | 48 min |
| Jul 24, 1:13 AM EDT | Severe Thunderstorm Warning | PHI | Bucks | 62 min |
| Jul 24, 10:43 AM EDT | Flash Flood Warning | PHI | Philadelphia | 76 min |
| Jul 24, 1:43 PM EDT | Areal Flood Advisory | PHI | Bucks, Philadelphia | 3 hr |
| Jul 24, 2:19 PM EDT | Areal Flood Advisory | PHI | Bucks, Montgomery, Philadelphia | 2 hr |
| Jul 24, 2:26 PM EDT | Flash Flood Warning | PHI | Bucks, Montgomery, Philadelphia | 2 hr |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.