Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1999
Severe Thunderstorm Warning 151, NWS Pittsburgh, PA
NWS Pittsburgh, PA issued this severe thunderstorm warning at Sep 29, 1999, 4:29 PM EDT for Lawrence County, Pennsylvania. It was in force for 61 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 29, 1999, 4:29 PM EDT (20:29 UTC)
- Expired
- Sep 29, 1999, 5:30 PM EDT
- In force
- 61 min
- Issued by
- NWS Pittsburgh, PA
- Area
- Whole counties
County Lawrence County, PA
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Sep 29, 4:40 PM EDT | Thunderstorm Wind | Ellwood City, PA | Thunderstorm winds downed several large trees and power lines. |
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 29, 3:45 PM EDT | Tornado Watch | SPC | 6 hr |
The nearest sounding before it
Pittsburgh, PA (KPIT), launched 12:00Z, 8.5 hours before the alert went out and 68 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
- 618 J/kg
- Mixed-layer CIN
- -36 J/kg
- Mixed-layer LCL
- 768 m above ground
- 0-6 km bulk shear
- 25 kt
- 0-1 km storm-relative helicity
- 120 m²/s²
- 0-3 km storm-relative helicity
- 138 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 1.6
The text
The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.
The office that day
Everything else NWS Pittsburgh, PA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 29, 3:18 PM EDT | Severe Thunderstorm Warning | PBZ | Washington | 57 min |
| Sep 29, 3:35 PM EDT | Severe Thunderstorm Warning | PBZ | Allegheny | 55 min |
| Sep 29, 4:06 PM EDT | Severe Thunderstorm Warning | PBZ | Beaver | 54 min |
| Sep 29, 4:20 PM EDT | Severe Thunderstorm Warning | PBZ | Butler | 55 min |
| Sep 29, 4:51 PM EDT | Severe Thunderstorm Warning | PBZ | Mercer | 54 min |
| Sep 29, 4:57 PM EDT | Severe Thunderstorm Warning | PBZ | Venango | 63 min |
| Sep 29, 6:02 PM EDT | Severe Thunderstorm Warning | PBZ | Armstrong | 58 min |
| Sep 29, 3:43 PM EDT | Severe Thunderstorm Warning | PBZ | Jefferson | 62 min |
| Sep 29, 4:11 PM EDT | Severe Thunderstorm Warning | PBZ | Columbiana | 49 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 1999Every severe thunderstorm warning in 1999
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.