Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 99, NWS Philadelphia/Mount Holly

July 10, 2001Northampton County, Pennsylvania; Warren County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 10, 2001, 6:15 PM EDT for Northampton County, Pennsylvania; Warren County, New Jersey. It was in force for 45 min. 2 reports 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: Jul 10, 2001, 6:15 PM EDT (22:15 UTC)
Expired: Jul 10, 2001, 7:00 PM EDT
In force: 45 min
Issued by: NWS Philadelphia/Mount Holly
Area: Whole counties

Counties Warren County, NJ, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 114 km from the middle of the area, began a volume at 22:16 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
Jul 10, 6:32 PM EDT	Thunderstorm Wind 50 E	Washington, NJ
Jul 10, 6:35 PM EDT	Thunderstorm Wind 52 E	Nazareth, 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
Jul 10, 1:45 PM EDT	Severe Thunderstorm Watch	SPC	7 hr
Jul 10, 3:00 PM EDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 10.3 hours before the alert went out and 169 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: 31 J/kg
Mixed-layer CIN: -142 J/kg
Mixed-layer LCL: 1637 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 40 m²/s²
0-3 km storm-relative helicity: 108 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.

000 
WUUS51 KPHI 102216
SVRPHI

NJC041-PAC095-102300-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
615 PM EDT TUE JUL 10 2001

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHAMPTON COUNTY IN EASTERN PENNSYLVANIA.
  SOUTHWESTERN WARREN COUNTY IN NORTHWEST NEW JERSEY.

* UNTIL 700 PM EDT.

* AT 611 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM... 3 MILES NORTHEAST OF BELFAST...MOVING
  SOUTHEAST AT 25 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  EASTON...OLD ORCHARD AT 630 PM.
  ALPHA AT 635 PM.

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.

$$

LAT...LON 4071 7503 4092 7516 4076 7555 4058 7531

GSS

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 10, 4:53 PM EDT	Severe Thunderstorm Warning	PHI	Carbon, Monroe	52 min
Jul 10, 5:40 PM EDT	Severe Thunderstorm Warning	PHI	Monroe, Northampton	35 min
Jul 10, 6:42 PM EDT	Severe Thunderstorm Warning	PHI	Lehigh	48 min
Jul 10, 5:33 PM EDT	Severe Thunderstorm Warning	PHI	Cumberland, Salem	42 min
Jul 10, 6:51 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon	24 min
Jul 10, 7:15 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Somerset	45 min
Jul 10, 7:39 PM EDT	Severe Thunderstorm Warning	PHI	Middlesex	21 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2001 Severe Thunderstorm Warnings in New Jersey, 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.