Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 243, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 10, 2021, 6:36 PM EDT for Berks County, 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
- Aug 10, 2021, 6:36 PM EDT (22:36 UTC)
- Expired
- Aug 10, 2021, 7:15 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 Berks County, PA, Chester County, PA
The radar
The Philadelphia radar (KDIX), 136 km from the middle of the area, began a volume at 22:37 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 12:00Z, 10.6 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
- 529 J/kg
- Mixed-layer CIN
- -120 J/kg
- Mixed-layer LCL
- 1096 m above ground
- 0-6 km bulk shear
- 14 kt
- 0-1 km storm-relative helicity
- 37 m²/s²
- 0-3 km storm-relative helicity
- 65 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
026
WUUS51 KPHI 102236
SVRPHI
PAC011-029-102315-
/O.NEW.KPHI.SV.W.0243.210810T2236Z-210810T2315Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
636 PM EDT Tue Aug 10 2021
The National Weather Service in Mount Holly NJ has issued a
* Severe Thunderstorm Warning for...
Central Berks County in eastern Pennsylvania...
North central Chester County in southeastern Pennsylvania...
* Until 715 PM EDT.
* At 636 PM EDT, a severe thunderstorm was located over Brickerville,
or near Ephrata, moving east at 25 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...
Reading, Wyomissing, Birdsboro, Kutztown, Fleetwood, Sinking
Spring, Laureldale, Womelsdorf, Wernersville, Robesonia, Leesport,
Honey Brook, Shoemakersville, Elverson, Bernville, Lyons, New
Morgan, Spring Ridge, Fairview Hgts and Glenmoore.
This includes the following highways...
Pennsylvania Turnpike between mile markers 296 and 309.
Interstate 176 in Pennsylvania between mile markers 1 and 11.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4057 7578 4005 7571 4006 7593 4011 7594
4014 7588 4036 7621 4042 7632
TIME...MOT...LOC 2236Z 263DEG 22KT 4025 7626
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
SFJ2 follow-up statements
321
WWUS51 KPHI 102259
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
659 PM EDT Tue Aug 10 2021
PAC011-029-102315-
/O.CON.KPHI.SV.W.0243.000000T0000Z-210810T2315Z/
Berks PA-Chester PA-
659 PM EDT Tue Aug 10 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 715 PM EDT
FOR CENTRAL BERKS AND NORTH CENTRAL CHESTER COUNTIES...
At 658 PM EDT, a severe thunderstorm was located over Adamstown, or 7
miles northeast of Ephrata, moving east at 25 mph.
HAZARD...60 mph wind gusts and penny size hail.
SOURCE...Radar indicated.
IMPACT...Damage to roofs, siding, trees, and power lines is
possible.
Locations impacted include...
Reading, Wyomissing, Birdsboro, Kutztown, Fleetwood, Sinking Spring,
Laureldale, Womelsdorf, Wernersville, Robesonia, Leesport, Honey
Brook, Shoemakersville, Elverson, Bernville, Lyons, New Morgan,
Spring Ridge, Fairview Hgts and Glenmoore.
This includes the following highways...
Pennsylvania Turnpike between mile markers 296 and 309.
Interstate 176 in Pennsylvania between mile markers 1 and 11.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Frequent cloud to ground lightning is occurring with this storm. Move
indoors immediately. Lightning is one of nature's leading killers.
Remember, if you can hear thunder, you are close enough to be struck
by lightning.
&&
LAT...LON 4057 7578 4005 7571 4006 7593 4011 7594
4014 7588 4036 7621 4042 7632
TIME...MOT...LOC 2258Z 263DEG 22KT 4027 7608
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
SFJ867
WWUS51 KPHI 102304
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
704 PM EDT Tue Aug 10 2021
PAC011-029-102315-
/O.CON.KPHI.SV.W.0243.000000T0000Z-210810T2315Z/
Berks PA-Chester PA-
704 PM EDT Tue Aug 10 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 715 PM EDT
FOR CENTRAL BERKS AND NORTH CENTRAL CHESTER COUNTIES...
At 704 PM EDT, a severe thunderstorm was located over Adamstown, or 7
miles southwest of Reading, moving east at 25 mph.
HAZARD...60 mph wind gusts and penny size hail.
SOURCE...Automated Weather Station.
IMPACT...Damage to roofs, siding, trees, and power lines is
possible.
Locations impacted include...
Reading, Wyomissing, Birdsboro, Kutztown, Fleetwood, Sinking Spring,
Laureldale, Womelsdorf, Wernersville, Robesonia, Leesport, Honey
Brook, Shoemakersville, Elverson, Bernville, Lyons, New Morgan,
Spring Ridge, Fairview Hgts and Glenmoore.
This includes the following highways...
Pennsylvania Turnpike between mile markers 296 and 309.
Interstate 176 in Pennsylvania between mile markers 1 and 11.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Frequent cloud to ground lightning is occurring with this storm. 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.
&&
LAT...LON 4057 7578 4005 7571 4006 7593 4011 7594
4014 7588 4036 7621 4042 7632
TIME...MOT...LOC 2304Z 263DEG 22KT 4027 7603
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
SFJThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 9, 10:10 PM EDT | Areal Flood Advisory | PHI | Carbon | 3 hr |
| Aug 10, 3:33 AM EDT | Excessive Heat Warning | PHI | Berks, Bucks, Chester, Delaware, Lehigh, Montgomery and 2 more | 4 days |
| Aug 10, 3:33 AM EDT | Heat Advisory | PHI | Berks, Carbon, Lehigh, Monroe, Northampton | 4 days |
| Aug 10, 5:58 AM EDT | Flash Flood Warning | PHI | Bucks | 2 hr |
| Aug 10, 3:06 PM EDT | Special Weather Statement | PHI | Berks | 24 min |
| Aug 10, 3:33 PM EDT | Special Weather Statement | PHI | Berks | 27 min |
| Aug 10, 3:52 PM EDT | Special Weather Statement | PHI | Berks, Carbon, Lehigh | 23 min |
| Aug 10, 4:01 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Carbon, Chester, Lehigh, Montgomery, Northampton | 44 min |
| Aug 10, 4:18 PM EDT | Areal Flood Advisory | PHI | Berks, Carbon, Lehigh | 3 hr |
| Aug 10, 4:33 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Bucks, Carbon, Chester, Lehigh, Monroe and 2 more | 42 min |
| Aug 10, 5:05 PM EDT | Special Weather Statement | PHI | Northampton | 25 min |
| Aug 10, 5:09 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Montgomery, Philadelphia | 51 min |
| Aug 10, 5:11 PM EDT | Special Weather Statement | PHI | Chester, Montgomery, Philadelphia | 34 min |
| Aug 10, 5:40 PM EDT | Special Weather Statement | PHI | Chester | 35 min |
| Aug 10, 5:58 PM EDT | Special Weather Statement | PHI | Philadelphia | 32 min |
| Aug 10, 7:10 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Chester, Montgomery | 65 min |
| Aug 10, 7:54 PM EDT | Severe Thunderstorm Warning | PHI | Chester | 51 min |
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.