Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 1, NWS Philadelphia/Mount Holly

March 9, 2002Berks County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Mar 9, 2002, 11:39 PM EST for Berks County, Pennsylvania. It was in force for 51 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: Mar 9, 2002, 11:39 PM EST (04:39 UTC)
Expired: Mar 10, 2002, 12:30 AM EST
In force: 51 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 04:40 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
Mar 10, 12:00 AM EST	Thunderstorm Wind 50 E	Wyomissing, 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
Mar 9, 8:30 PM EST	Severe Thunderstorm Watch	SPC	5 hr
Mar 9, 11:30 PM EST	Severe Thunderstorm Watch	SPC	4 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 4.7 hours before the alert went out and 206 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: 445 J/kg
Mixed-layer CIN: -17 J/kg
Mixed-layer LCL: 657 m above ground
0-6 km bulk shear: 56 kt
0-1 km storm-relative helicity: 375 m²/s²
0-3 km storm-relative helicity: 418 m²/s²
Significant tornado parameter: 0.6
Supercell composite: 4.0

Open this sounding in Storm Lab

The text

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

000 
WUUS51 KPHI 100439
SVRPHI
PAC011-100530-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1137 PM EST SAT MAR 9 2002

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

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

* UNTIL 1230 AM EST.

* AT 1135 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  SEVERE THUNDERSTORMS... ALONG A LINE EXTENDING FROM 16 MILES
  NORTHWEST OF HAMBURG TO 19 MILES SOUTHWEST OF WOMELSDORF...MOVING
  EAST AT 40 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  STRAUSSTOWN AT 1150 PM.
  WOMELSDORF...BERNVILLE AT MIDNIGHT.
  HAMBURG AT 1205 AM.
  WERNERSVILLE...LENHARTSVILLE...LEESPORT AT 1210 AM.
  READING AT 1220 AM.
  KUTZTOWN...FLEETWOOD AT 1225 AM.

DAMAGING WINDS IN EXCESS OF 55 MPH ARE EXPECTED FROM THIS STORM. SEEK
SHELTER IN A STURDY STRUCTURE UNTIL THE STORM HAS PASSED.

REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE IN MOUNT HOLLY.

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 300 AM SUNDAY 
MORNING FOR EASTERN PENNSYLVANIA. 

$$

LAT...LON 4054 7629 4045 7639 4016 7588 4043 7556
          4068 7589

AMC

The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 9, 11:43 PM EST	Severe Thunderstorm Warning	PHI	Carbon	32 min
Mar 10, 12:05 AM EST	Severe Thunderstorm Warning	PHI	Lehigh, Monroe, Northampton	55 min
Mar 10, 2:12 AM EST	Severe Thunderstorm Warning	PHI	Bucks	18 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2002 Every severe thunderstorm warning in 2002

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.