Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1987
Severe Thunderstorm Warning 45, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Sep 22, 1987, 3:56 PM EDT for Bucks County, Montgomery County, Pennsylvania. It was in force for 34 min. 4 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
- Sep 22, 1987, 3:56 PM EDT (19:56 UTC)
- Expired
- Sep 22, 1987, 4:30 PM EDT
- In force
- 34 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Whole counties
Counties Bucks County, PA, Montgomery County, PA
The radar
The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Sep 22, 4:04 PM EDT | Hail 0.75 | Montgomery, PA | |
| Sep 22, 4:30 PM EDT | Thunderstorm Wind 0 | Montgomery, PA | |
| Sep 22, 4:39 PM EDT | Hail 0.75 | Montgomery, PA | |
| Sep 22, 4:40 PM EDT | Hail 0.75 | Bucks, 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. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.
The nearest sounding before it
Atlantic City In, NJ (KACY), launched 12:00Z, 7.9 hours before the alert went out and 111 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1741 m above ground
- 0-6 km bulk shear
- 39 kt
- 0-1 km storm-relative helicity
- 20 m²/s²
- 0-3 km storm-relative helicity
- 34 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KPHL 221956 SVRPHL PAC017-091-222030- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE PHILADELPHIA PA 356 PM EDT TUE SEP 22 1987 THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 430 PM EDT FOR PEOPLE IN THE FOLLOWING COUNTIES OF SOUTHEAST PENNSYLVANIA...SOUTHERN BUCKS AND SOUTHERN MONTGOMERY AT 350 PM EDT A SPOTTER IN REPORTED DIME SIZE HAIL IN LANSDALE PENNSYLVANIA. THE STORM PRODUCING THIS HAIL IS MOVING EAST AT 20 MILES AN HOUR. THIS IS A DANGEROUS STORM AND PEOPLE IN THE WARNED AREA SHOULD BE PREPARED FOR STRONG DAMAGING WINDS...LARGE HAIL...VERY HEAVY RAIN AND LIGHTNING. SHOULD THE STORM APPROACH YOU...SEEK IMMEDIATE SHELTER. MOBILE HOMES ARE MOST VULNERABLE TO HIGH WINDS AND SHOULD BE AVOIDED. DPG
The office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 22, 2:43 PM EDT | Severe Thunderstorm Warning | PHI | Bucks | 62 min |
| Sep 22, 3:58 PM EDT | Severe Thunderstorm Warning | PHI | Chester, Montgomery | 42 min |
| Sep 22, 4:34 PM EDT | Severe Thunderstorm Warning | PHI | Bucks | 41 min |
| Sep 22, 4:34 PM EDT | Severe Thunderstorm Warning | PHI | Montgomery, Philadelphia | 41 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 1987Every severe thunderstorm warning in 1987
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.