Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2007

Severe Thunderstorm Warning 197, NWS Philadelphia/Mount Holly

August 17, 2007Monroe County, Northampton County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 17, 2007, 2:41 PM EDT for Monroe County, Northampton County, Pennsylvania. It was in force for 79 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Aug 17, 2007, 2:41 PM EDT (18:41 UTC)
Expired: Aug 17, 2007, 4:00 PM EDT
In force: 79 min
Issued by: NWS Philadelphia/Mount Holly
Area: Counties, with a storm outline in the text

Counties Monroe County, PA, Northampton County, PA

What was reported inside it

Time	Report	Where	Remark
Aug 17, 3:07 PM EDT	HAIL 0.75	Brodheadsville, PA	PENNY SIZE HAIL REPORTED IN BRODHEADSVILLE.
Aug 17, 3:27 PM EDT	HAIL 1	Nazareth, PA	QUARTER SIZE HAIL REPORTED IN NAZARETH.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

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

Issued	Product	Office	Lasted
Aug 17, 1:37 PM EDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 6.7 hours before the alert went out and 210 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: 120 J/kg
Mixed-layer CIN: -267 J/kg
Mixed-layer LCL: 1465 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: -31 m²/s²
0-3 km storm-relative helicity: 44 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.4

Open this sounding in Storm Lab

The text

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

000 
WUUS51 KPHI 171841
SVRPHI
PAC089-095-172000-
/O.NEW.KPHI.SV.W.0197.070817T1841Z-070817T2000Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
241 PM EDT FRI AUG 17 2007

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHAMPTON COUNTY IN EASTERN PENNSYLVANIA...
  SOUTHERN MONROE COUNTY IN NORTHEAST PENNSYLVANIA...

* UNTIL 400 PM EDT

* AT 238 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED 6 MILES
  NORTHWEST OF DANIELSVILLE...OR ABOUT 19 MILES NORTH OF ALLENTOWN...
  AND MOVING EAST AT 25 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  DANIELSVILLE BY 250 PM EDT...
  BEERSVILLE BY 300 PM EDT...
  ROSSLAND BY 305 PM EDT...
  6 MILES NORTH OF BATH BY 310 PM EDT...
  WIND GAP BY 315 PM EDT...
  BELFAST AND NAZARETH BY 320 PM EDT...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 800 PM EDT FRIDAY
EVENING FOR NORTHERN DELAWARE AND NEW JERSEY AND EASTERN
PENNSYLVANIA.

LAT...LON 4093 7513 4083 7512 4075 7519 4064 7523
      4060 7529 4079 7562 4082 7549 4094 7557
      4095 7557 4097 7553 4099 7550
TIME...MOT...LOC 1841Z 283DEG 22KT 4085 7559

$$

JJM

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 17, 1:48 PM EDT	Severe Thunderstorm Warning	PHI	Chester	72 min
Aug 17, 2:07 PM EDT	Severe Thunderstorm Warning	PHI	Carbon	68 min
Aug 17, 2:14 PM EDT	Tornado Warning	PHI	Chester	46 min
Aug 17, 2:19 PM EDT	Tornado Warning	PHI	Carbon	26 min
Aug 17, 2:20 PM EDT	Severe Thunderstorm Warning	PHI	Northampton	70 min
Aug 17, 2:36 PM EDT	Severe Thunderstorm Warning	PHI	Delaware	54 min
Aug 17, 2:43 PM EDT	Severe Thunderstorm Warning	PHI	Bucks	62 min
Aug 17, 2:45 PM EDT	Tornado Warning	PHI	Carbon, Northampton	45 min
Aug 17, 2:54 PM EDT	Severe Thunderstorm Warning	PHI	Lehigh	66 min
Aug 17, 4:42 PM EDT	Severe Thunderstorm Warning	PHI	Carbon	19 min
Aug 17, 4:45 PM EDT	Severe Thunderstorm Warning	PHI	Monroe, Northampton	60 min
Aug 17, 4:51 PM EDT	Severe Thunderstorm Warning	PHI	Lehigh, Northampton	43 min
Aug 17, 5:17 PM EDT	Severe Thunderstorm Warning	PHI	Bucks	58 min
Aug 17, 7:56 PM EDT	Severe Thunderstorm Warning	PHI	Montgomery	19 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2007 Every severe thunderstorm warning in 2007

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive.