Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 75, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 9, 2021, 8:21 PM EDT for Chester County, Pennsylvania. It was in force for 39 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
- Jun 9, 2021, 8:21 PM EDT (00:21 UTC)
- Expired
- Jun 9, 2021, 9:00 PM EDT
- In force
- 39 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
County Chester County, PA
The radar
The Dover AFB radar (KDOX), 121 km from the middle of the area, began a volume at 00:20 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, 0.4 hours before the alert went out and 164 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
- 186 J/kg
- Mixed-layer CIN
- -73 J/kg
- Mixed-layer LCL
- 1395 m above ground
- 0-6 km bulk shear
- 11 kt
- 0-1 km storm-relative helicity
- 37 m²/s²
- 0-3 km storm-relative helicity
- 30 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
122
WUUS51 KPHI 100021
SVRPHI
PAC029-100100-
/O.NEW.KPHI.SV.W.0075.210610T0021Z-210610T0100Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
821 PM EDT Wed Jun 9 2021
The National Weather Service in Mount Holly NJ has issued a
* Severe Thunderstorm Warning for...
Southwestern Chester County in southeastern Pennsylvania...
* Until 900 PM EDT.
* At 821 PM EDT, a severe thunderstorm was located over Parkesburg,
or 13 miles southeast of New Holland, moving southeast at 35 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...
Coatesville, Kennett Square, Oxford, Parkesburg, West Grove,
Homeville, Cochranville, Ladenberg, Kemblesville, North Star,
Atglen, South Coatesville, Avondale, Modena and Toughkenamon.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
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 3983 7602 3987 7601 3987 7599 3992 7600
3994 7598 3995 7600 4006 7593 3987 7559
3983 7560 3981 7570 3977 7575 3972 7577
3972 7594 3983 7604
TIME...MOT...LOC 0021Z 313DEG 30KT 3995 7593
HAIL...0.75IN
WIND...60MPH
$$
Davis1 follow-up statement
826
WWUS51 KPHI 100051
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
851 PM EDT Wed Jun 9 2021
PAC029-100100-
/O.EXP.KPHI.SV.W.0075.000000T0000Z-210610T0100Z/
Chester PA-
851 PM EDT Wed Jun 9 2021
...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN CHESTER COUNTY
WILL EXPIRE AT 900 PM EDT...
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire. However, gusty
winds and heavy rain are still possible with this thunderstorm.
LAT...LON 3983 7602 3987 7601 3987 7599 3992 7600
3994 7598 3995 7600 4006 7593 3987 7559
3983 7560 3981 7570 3977 7575 3972 7577
3972 7594 3983 7604
TIME...MOT...LOC 0050Z 313DEG 30KT 3978 7570
$$
DavisThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 9, 8:43 PM EDT | Areal Flood Advisory | PHI | Chester | 2 hr |
Nearby
Severe 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.