Alert archive / Pennsylvania / Special Weather Statements in 2021

Special Weather Statement, NWS Philadelphia/Mount Holly

August 1, 2021Berks County, Pennsylvania

NWS Philadelphia/Mount Holly issued this special weather statement at Aug 1, 2021, 7:50 PM EDT for Berks County, Pennsylvania. It was in force for 40 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 1, 2021, 7:50 PM EDT (23:50 UTC)
Expired
Aug 1, 2021, 8:30 PM EDT
In force
40 min
Issued by
NWS Philadelphia/Mount Holly

County Berks County, PA

The radar

The Philadelphia radar (KDIX), 134 km from the middle of the area, began a volume at 23:51 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, 11.8 hours before the alert went out and 200 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 12:00Z on 2021-08-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 222 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 12:00Z on 2021-08-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 3 square meters per square second.1939587897Sfc1 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
222 J/kg
Mixed-layer CIN
-8 J/kg
Mixed-layer LCL
612 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
3 m²/s²
0-3 km storm-relative helicity
42 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

465 
WWUS81 KPHI 012350
SPSPHI

Special Weather Statement
National Weather Service Mount Holly NJ
750 PM EDT Sun Aug 1 2021

PAZ060-020030-
Berks-
750 PM EDT Sun Aug 1 2021

...A LINE OF STRONG THUNDERSTORMS WILL AFFECT SOUTHEASTERN BERKS
COUNTY...

At 749 PM EDT, radar indicated strong thunderstorms were located
along a line extending from near Fairview Hgts to Denver. Movement
was east at 30 mph.

Wind gusts up to 40 mph are possible with these storms.

Locations impacted include...
Reading, Wyomissing, Birdsboro, Sinking Spring, Laureldale,
Wernersville, Robesonia, Leesport, Bechtelsville, New Morgan, Spring
Ridge, Fairview Hgts, Gilbertsville, Shillington, West Reading,
Boyertown, Mount Penn, Mohnton, Kenhorst and St. Lawrence.

This includes the following highways...
 Pennsylvania Turnpike between mile markers 296 and 299.
 Interstate 176 in Pennsylvania between mile markers 1 and 11.

If outdoors, consider seeking shelter inside a building.

LAT...LON 4046 7604 4037 7559 4025 7569 4014 7587
      4032 7617
TIME...MOT...LOC 2349Z 284DEG 26KT 4040 7603 4025 7616 

$$

Staarmann

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 1, 6:19 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe41 min
Aug 1, 7:18 PM EDTSpecial Weather StatementPHIBerks27 min

Nearby

Special Weather Statements in Pennsylvania, 2021Every special weather statement 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.