Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 335, NWS Philadelphia/Mount Holly

August 27, 2026Berks County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 27, 2026, 8:40 PM EDT for Berks County, Pennsylvania. It was in force for 50 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 27, 2026, 8:40 PM EDT (00:40 UTC)
Expired
Aug 27, 2026, 9:30 PM EDT
In force
50 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

County Berks County, PA

The radar

The State College radar (KCCX), 148 km from the middle of the area, began a volume at 00:41 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 27, 12:51 PM EDTSevere Thunderstorm WatchSPC9 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 0.7 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.

Skew-T log-pSkew-T log-p diagram, Washington/Dulle, VA at 00:00Z on 2026-08-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1155 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 00:00Z on 2026-08-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 27 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1155 J/kg
Mixed-layer CIN
-14 J/kg
Mixed-layer LCL
1287 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
27 m²/s²
0-3 km storm-relative helicity
65 m²/s²
Significant tornado parameter
0.3
Supercell composite
2.3

Open this sounding in Storm Lab

The text

As transmitted.

679 
WUUS51 KPHI 280040
SVRPHI
PAC011-280130-
/O.NEW.KPHI.SV.W.0335.260828T0040Z-260828T0130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
Issued by National Weather Service New York NY
840 PM EDT Thu Aug 27 2026

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  West central Berks County in eastern Pennsylvania...

* Until 930 PM EDT.

* At 840 PM EDT, a severe thunderstorm was located near
  Fredericksburg, or 8 miles northwest of Myerstown, moving east at
  10 mph.

  HAZARD...60 mph wind gusts and penny size hail.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to trees and power lines.

* This severe thunderstorm will remain over mainly rural areas of
  west central Berks County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 4049 7642 4051 7637 4051 7635 4052 7634
      4052 7626 4053 7622 4037 7623 4049 7644
TIME...MOT...LOC 0040Z 260DEG 9KT 4048 7639 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$
2 follow-up statements
631 
WWUS51 KPHI 280101
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
Issued by National Weather Service New York NY
901 PM EDT Thu Aug 27 2026

PAC011-280130-
/O.CON.KPHI.SV.W.0335.000000T0000Z-260828T0130Z/
Berks PA-
901 PM EDT Thu Aug 27 2026

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 930 PM EDT
FOR WEST CENTRAL BERKS COUNTY...

At 900 PM EDT, a severe thunderstorm was located near Pine Grove, or
7 miles north of Myerstown, moving east at 10 mph.

HAZARD...60 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

IMPACT...Expect damage to trees and power lines.

This severe thunderstorm will remain over mainly rural areas of west
central Berks County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 4049 7642 4051 7637 4051 7635 4052 7634
      4052 7626 4053 7622 4037 7623 4049 7644
TIME...MOT...LOC 0100Z 260DEG 9KT 4049 7632 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$
716 
WWUS51 KPHI 280120
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
Issued by National Weather Service New York NY
920 PM EDT Thu Aug 27 2026

PAC011-280130-
/O.EXP.KPHI.SV.W.0335.000000T0000Z-260828T0130Z/
Berks PA-
920 PM EDT Thu Aug 27 2026

...THE SEVERE THUNDERSTORM WARNING FOR WEST CENTRAL BERKS COUNTY WILL
EXPIRE AT 930 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 heavy rain
is still possible with this thunderstorm.

A Severe Thunderstorm Watch remains in effect until 1000 PM EDT for
eastern Pennsylvania.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Mount Holly NJ.

LAT...LON 4049 7642 4051 7637 4051 7635 4052 7634
      4052 7626 4053 7622 4037 7623 4049 7644
TIME...MOT...LOC 0120Z 260DEG 9KT 4050 7627 

$$

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 27, 8:09 PM EDTAreal Flood WarningPHIBucks, Montgomery5 hr
Aug 27, 8:16 PM EDTFlash Flood WarningPHIBerks4 hr
Aug 27, 9:09 PM EDTAreal Flood WarningPHIBucks, Chester, Montgomery4 hr
Aug 27, 9:21 PM EDTFlash Flood WarningPHIBerks3 hr
Aug 27, 9:32 PM EDTRiver Flood WarningPHIBucks6 hr
Aug 27, 10:22 PM EDTSevere Thunderstorm WarningPHIBerks, Chester38 min
Aug 27, 10:36 PM EDTFlash Flood WarningPHIBerks, Chester, Montgomery3 hr

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.