Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 116, NWS State College, PA
NWS State College, PA issued this severe thunderstorm warning at Jul 21, 1997, 10:18 PM EDT for Franklin County, Pennsylvania. It was in force for 47 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
- Jul 21, 1997, 10:18 PM EDT (02:18 UTC)
- Expired
- Jul 21, 1997, 11:05 PM EDT
- In force
- 47 min
- Issued by
- NWS State College, PA
- Area
- Whole counties
County Franklin County, PA
The radar
The Sterling radar (KLWX), 108 km from the middle of the area, began a volume at 02:17 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 21, 10:35 PM EDT | Thunderstorm Wind 51 | Green Vlg, PA | Trees were blown down in Green Village north of Chambersburg. |
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 nearest sounding before it
Washington/Dulle, VA (KIAD), launched 00:00Z, 2.3 hours before the alert went out and 112 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
- 2692 J/kg
- Mixed-layer CIN
- -1 J/kg
- Mixed-layer LCL
- 1120 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 51 m²/s²
- 0-3 km storm-relative helicity
- 87 m²/s²
- Significant tornado parameter
- 1.1
- Supercell composite
- 5.6
The text
The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.
What forecasters said that day
The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS State College, PA wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 21, 8:54 PM EDT, 1 hour 24 minutes earlier.
Area forecast discussion, Jul 21, 8:54 PM EDT, 1 hour 24 minutes before
CENTRAL PENNSYLVANIA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 845 PM EDT MON JUL 21 1997 ...DISCUSSION... A VERY COMPLEX WEATHER PATTERN.... SFC CHART SHOWS A WAVY FRONTAL BNDRY STRETCHING FROM CT WESTWARD TO A SFC LOW PRESSURE IN NE PA THEN INTO WESTERN NY. A TROF EXTENDS SOUTHWARD ACROSS E PA INTO N-CENTRAL VA. MOISTURE HAS BEEN POOLING EAST OF THIS BNDRY...AND IN FACT TSTMS HAVE BEEN FIRING ALONG THIS BNDRY IN N VA. NONE OF THE MODELS CORRECTLY FORECASTED CURRENT CONDITIONS. THE MESOETA APPEARS TO BE HOLDING UP THE BEST. SHOWERS PUSHING INTO W PA HAVING A DIFFICULT TIME MOVING INTO CENTRAL PA BECAUSE OF THE VERY DRY AIRMASS. MESOETA HOWEVER FCST MUCH OF CENTRAL PA TO MOISTEN UP OVER NIGHT SO EXPECT SHOWERS TO EVENTUALLY OVERSPREAD MOST OF PA BY MORNING. OTHER ACTIVITY ACROSS N VA MAY SLIDE INTO SE PA LATER TONIGHT AND BEARS WATCHING. SEE NO REASON TO DEVIATE FROM CURRENT FCST. WINTHER
The office that day
Everything else NWS State College, PA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 21, 10:46 PM EDT | Severe Thunderstorm Warning | CTP | Schuylkill | 64 min |
| Jul 21, 11:23 PM EDT | Severe Thunderstorm Warning | CTP | Dauphin, Lebanon | 47 min |
| Jul 22, 12:11 AM EDT | Severe Thunderstorm Warning | CTP | Lancaster, Lebanon | 64 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 1997Every severe thunderstorm warning in 1997
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.