Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 137, NWS Philadelphia/Mount Holly

September 4, 2001Berks County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Sep 4, 2001, 3:01 PM EDT for Berks County, Pennsylvania. It was in force for 59 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued: Sep 4, 2001, 3:01 PM EDT (19:01 UTC)
Expired: Sep 4, 2001, 4:00 PM EDT
In force: 59 min
Issued by: NWS Philadelphia/Mount Holly
Area: Whole counties

County Berks County, PA

The radar

The Philadelphia radar (KDIX), 139 km from the middle of the area, began a volume at 19:04 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
Sep 4, 3:15 PM EDT	Thunderstorm Wind 51 M	Bernville, PA

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The watch it was issued in

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

Issued	Product	Office	Lasted
Sep 4, 3:00 PM EDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 7.0 hours before the alert went out and 106 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 35 J/kg
Mixed-layer CIN: -94 J/kg
Mixed-layer LCL: 800 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 95 m²/s²
0-3 km storm-relative helicity: 80 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

808 
WUUS51 KPHI 041902
SVRPHI
PAC011-042000-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
301 PM EDT TUE SEP 4 2001

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  BERKS COUNTY IN EASTERN PENNSYLVANIA.

* UNTIL 400 PM EDT.

* AT 259 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM... 7 MILES NORTH OF STRAUSSTOWN...MOVING
  SOUTHEAST AT 40 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  HAMBURG...BERNVILLE AT 310 PM.
  LENHARTSVILLE AT 315 PM.
  LEESPORT...WERNERSVILLE AT 320 PM.
  KUTZTOWN AT 325 PM.
  FLEETWOOD...READING AT 330 PM.
  BIRDSBORO AT 340 PM.

DAMAGING WINDS IN EXCESS OF 58 MPH ARE EXPECTED FROM THIS STORM. SEEK
SHELTER IN A STURDY STRUCTURE UNTIL THE STORM HAS PASSED.

INTENSE LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS IF 
POSSIBLE. WHEN INDOORS...STAY AWAY FROM WINDOWS AND DOORS AND AVOID 
USING TELEPHONES UNLESS IT IS AN EMERGENCY. IF OUTDOORS...STAY AWAY 
FROM ISOLATED HIGH OBJECTS SUCH AS TREES.

FOR THE LATEST STORM INFORMATION...PLEASE TUNE TO NOAA WEATHER
RADIO...YOUR LOCAL RADIO OR TELEVISION STATION...OR YOUR CABLE
TELEVISION OUTLET.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM TUESDAY
EVENING FOR NORTHERN DELAWARE AND NORTHEAST MARYLAND AND NORTHWESTERN
NEW JERSEY AND SOUTHEASTERN PENNSYLVANIA.

$$

LAT...LON 4049 7638 4017 7590 4046 7558 4068 7593
EBERWINE

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 4, 3:59 PM EDT	Severe Thunderstorm Warning	PHI	Chester	61 min
Sep 4, 4:41 PM EDT	Severe Thunderstorm Warning	PHI	Delaware	49 min
Sep 4, 5:23 PM EDT	Severe Thunderstorm Warning	PHI	Chester	52 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2001 Every severe thunderstorm warning in 2001

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.