Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2026
Severe Thunderstorm Warning 208, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 21, 2026, 3:37 PM EDT for Chester County, Delaware County, Pennsylvania. It was in force for 53 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
- Jul 21, 2026, 3:37 PM EDT (19:37 UTC)
- Expired
- Jul 21, 2026, 4:30 PM EDT
- In force
- 53 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
The radar
The Philadelphia radar (KDIX), 113 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 |
|---|---|---|---|
| Jul 21, 4:02 PM EDT | TSTM WND DMG | East Bradford Twp, PA | Downed tree on US 322 both directions between NORTH CREEK RD and COPELAND SCHOOL RD. There is a lane restriction. Time estimated from radar. |
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 21, 2:06 PM EDT | Tornado Watch | SPC | 7 hr |
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 12:00Z, 7.6 hours before the alert went out and 181 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
- 941 J/kg
- Mixed-layer CIN
- -113 J/kg
- Mixed-layer LCL
- 772 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 68 m²/s²
- 0-3 km storm-relative helicity
- 112 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 0.9
The text
As transmitted.
141
WUUS51 KPHI 211937
SVRPHI
PAC029-045-212030-
/O.NEW.KPHI.SV.W.0208.260721T1937Z-260721T2030Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
337 PM EDT Tue Jul 21 2026
The National Weather Service in Mount Holly NJ has issued a
* Severe Thunderstorm Warning for...
Central Chester County in southeastern Pennsylvania...
Southwestern Delaware County in southeastern Pennsylvania...
* Until 430 PM EDT.
* At 337 PM EDT, a severe thunderstorm was located near Coatesville,
or 12 miles west of West Chester, 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...
West Chester, Coatesville, Westtown, Downingtown, Parkesburg,
Cheyney, Elam, Marshallton, Chelsea, Lionville-Marchwood,
Gradyville, Paoli, Lionville, Concordville, Lima, West Goshen,
Malvern, Chester Heights, South Coatesville, and Modena.
This includes Pennsylvania Turnpike between mile markers 316 and 318,
and between mile markers 320 and 323.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A Tornado Watch remains in effect until 900 PM EDT for southeastern
Pennsylvania.
For your protection move to an interior room on the lowest floor of a
building.
A Tornado Watch remains in effect until 900 PM EDT for southeastern
Pennsylvania.
&&
LAT...LON 3988 7592 4001 7592 4009 7546 3983 7544
TIME...MOT...LOC 1937Z 265DEG 27KT 3994 7584
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
AKL1 follow-up statement
508
WWUS51 KPHI 212012 RRA
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
412 PM EDT Tue Jul 21 2026
PAC029-045-212030-
/O.CON.KPHI.SV.W.0208.000000T0000Z-260721T2030Z/
Chester PA-Delaware PA-
412 PM EDT Tue Jul 21 2026
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 430 PM EDT
FOR EAST CENTRAL CHESTER AND WEST CENTRAL DELAWARE COUNTIES...
At 412 PM EDT, a severe thunderstorm was located over Westtown, or
over West Chester, moving east at 40 mph.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Damage to roofs, siding, trees, and power lines is
possible.
Locations impacted include...
West Chester, Westtown, Gradyville, Cheyney, Lima, West Goshen, and
Chester Heights.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A Tornado Watch remains in effect until 900 PM EDT for southeastern
Pennsylvania.
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 3990 7565 4000 7565 4003 7546 3988 7544
TIME...MOT...LOC 2012Z 267DEG 35KT 3996 7555
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
AKLThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 21, 2:18 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Lehigh | 42 min |
| Jul 21, 2:57 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Lehigh, Northampton | 37 min |
| Jul 21, 3:47 PM EDT | Severe Thunderstorm Warning | PHI | Carbon, Monroe | 43 min |
| Jul 21, 3:58 PM EDT | Severe Thunderstorm Warning | PHI | Chester, Delaware | 47 min |
| Jul 21, 4:23 PM EDT | Severe Thunderstorm Warning | PHI | Chester, Delaware, Montgomery, Philadelphia | 52 min |
| Jul 21, 4:31 PM EDT | Flash Flood Warning | PHI | Chester, Delaware | 96 min |
| Jul 21, 4:38 PM EDT | Flash Flood Warning | PHI | Chester, Delaware, Montgomery, Philadelphia | 4 hr |
| Jul 21, 4:43 PM EDT | Severe Thunderstorm Warning | PHI | Chester, Delaware | 47 min |
| Jul 21, 5:30 PM EDT | Severe Thunderstorm Warning | PHI | Delaware | 45 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 2026Every severe thunderstorm warning in 2026
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.