Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2002
Severe Thunderstorm Warning 117, NWS La Crosse, WI
NWS La Crosse, WI issued this severe thunderstorm warning at Sep 29, 2002, 11:17 PM CDT for Clark County, Jackson County, Wisconsin. It was in force for 58 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
- Sep 29, 2002, 11:17 PM CDT (04:17 UTC)
- Expired
- Sep 30, 2002, 12:15 AM CDT
- In force
- 58 min
- Issued by
- NWS La Crosse, WI
- Area
- Counties, with a storm outline in the text
Counties Clark County, WI, Jackson County, WI
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Sep 29, 11:21 PM CDT | Thunderstorm Wind 52 E | Neillsville, WI | |
| Sep 29, 11:45 PM CDT | Hail 0.75 | Price, WI |
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.
Did it verify
Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.
Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.
The nearest sounding before it
Green Bay/Straub, WI (KGRB), launched 00:00Z, 4.3 hours before the alert went out and 207 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
- 1115 J/kg
- Mixed-layer CIN
- -165 J/kg
- Mixed-layer LCL
- 760 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km storm-relative helicity
- 210 m²/s²
- 0-3 km storm-relative helicity
- 224 m²/s²
- Significant tornado parameter
- 0.3
- Supercell composite
- 1.6
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 La Crosse, WI wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 29, 8:30 PM CDT, 2 hours 47 minutes earlier.
Area forecast discussion, Sep 29, 8:30 PM CDT, 2 hours 47 minutes before
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LA CROSSE WI 830 PM CDT SUN SEP 29 2002 ...THUNDERSTORMS RAPIDLY DEVELOPING... GEOSTROPHIC SURFACE WIND ANALYSIS AT 21Z SHOWED THE LOW LEVEL JET DEVELOPMENT WOULD OCCUR OVER IOWA AND INTO SOUTHERN MINNESOTA. THIS IS NOW COMING TO FRUITION GIVEN THE INCREASING LOW LEVEL FLOW /UP TO 40 KNOTS/ DEPICTED BY THE PROFILER DATA AT 850 MB. THE SUBSEQUENT FORCING ALONG THE WARM FRONT OVER SOUTHERN MINNESOTA AND NORTHERN IOWA IS CAUSING RAPID DEVELOPMENT OF THUNDERSTORMS. THESE STORMS SHOULD REMAIN ELEVATED...SINCE THE CAP IS TOO STRONG FOR SURFACE BASED STORMS /CIN 300-400 J/KG/. THUS...THE MAIN SEVERE WEATHER THREAT SHOULD BE LARGE HAIL NORTH OF THE WARM FRONT. .LSE...NONE. KRC
In the hours before
Special weather statement, Sep 29, 8:43 PM CDT, 2 hours 34 minutes before
IAZ008>011-018-019-029-030-MNZ079-086>088-094>096-WIZ017-029-032>034- 041>044-053>055-061-300500- HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE LA CROSSE WI 843 PM CDT SUN SEP 29 2002 HAZARD - SEVERE THUNDERSTORMS WITH LARGE HAIL. TIMING - 900 PM TO 300 AM. LOCATION - NORTHEAST IOWA...SOUTHEAST MINNESOTA...CENTRAL AND SOUTHWEST WISCONSIN. DISCUSSION - THUNDERSTORMS ARE DEVELOPING RAPIDLY OVER SOUTHERN MINNESOTA AND NORTHERN IOWA. THESE STORMS ARE DEVELOPING IN THE AREA WHERE STRONG LOW LEVEL WINDS ARE INTERACTING WITH A WARM FRONT. THESE LOW LEVEL WINDS WILL BE INCREASING OVER THE NEXT FEW HOURS...THEN THEY WILL MOVE TO THE EAST. THIS WILL CAUSE THE STORMS TO INCREASE IN STRENGTH AND AREAL COVERAGE...EVENTUALLY EVOLVING INTO A COMPLEX OF THUNDERSTORMS. THE STORMS WILL BE MOVING INTO SOUTHEAST MINNESOTA AND NORTHEAST IOWA AFTER 900 PM...AND INTO WISCONSIN BEFORE MIDNIGHT. SPOTTER INFORMATION - SPOTTER ACTIVATION MAY BE NEEDED. KRC
The office that day
Everything else NWS La Crosse, WI issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 29, 9:43 PM CDT | Severe Thunderstorm Warning | ARX | Buffalo | 32 min |
| Sep 30, 5:18 PM CDT | Severe Thunderstorm Warning | ARX | Buffalo | 27 min |
| Sep 30, 5:22 PM CDT | Severe Thunderstorm Warning | ARX | Taylor | 38 min |
| Sep 30, 5:53 PM CDT | Severe Thunderstorm Warning | ARX | Taylor | 37 min |
| Sep 30, 5:58 PM CDT | Severe Thunderstorm Warning | ARX | Trempealeau | 32 min |
| Sep 30, 6:04 PM CDT | Severe Thunderstorm Warning | ARX | Jackson | 26 min |
| Sep 30, 6:28 PM CDT | Severe Thunderstorm Warning | ARX | Jackson | 62 min |
| Sep 30, 6:30 PM CDT | Severe Thunderstorm Warning | ARX | Taylor | 45 min |
| Sep 30, 6:45 PM CDT | Tornado Warning | ARX | Taylor | 30 min |
| Sep 30, 6:53 PM CDT | Severe Thunderstorm Warning | ARX | Clark | 52 min |
| Sep 30, 6:53 PM CDT | Severe Thunderstorm Warning | ARX | Clark | |
| Sep 30, 6:57 PM CDT | Tornado Warning | ARX | Clark | 48 min |
Nearby
Severe Thunderstorm Warnings in Wisconsin, 2002Every severe thunderstorm warning in 2002
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.