Alert archive / Wisconsin / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 220, NWS Twin Cities, MN

September 1, 1997Pepin County, Wisconsin

NWS Twin Cities, MN issued this severe thunderstorm warning at Sep 1, 1997, 6:57 PM CDT for Pepin County, Wisconsin. It was in force for 33 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 1, 1997, 6:57 PM CDT (23:57 UTC)
Expired
Sep 1, 1997, 7:30 PM CDT
In force
33 min
Issued by
NWS Twin Cities, MN
Area
Whole counties

County Pepin County, WI

The radar

The La Crosse radar (KARX), 106 km from the middle of the area, began a volume at 23:57 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

TimeReportWhereRemark
Sep 1, 7:30 PM CDTThunderstorm Wind 55Ella, WIHome under construction destroyed. Metal shed damaged. Estimated windspeed.

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.

IssuedProductOfficeLasted
Sep 1, 1:45 PM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 12.0 hours before the alert went out and 122 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-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 1997-09-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 751 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 12:00Z on 1997-09-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 215 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
751 J/kg
Mixed-layer CIN
-155 J/kg
Mixed-layer LCL
739 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
215 m²/s²
0-3 km storm-relative helicity
203 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.7

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KMSP 012359 RRA
SVRMSP
WIC091-020030-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
657 PM CDT MON SEP 1 1997


* SEVERE THUNDERSTORM WARNING FOR
  PEPIN COUNTY - WEST CENTRAL WISCONSIN

* UNTIL 730 PM CDT

* SOME LOCATIONS AFFECTED
    ARKANSAW
    DURAND
    PORCUPINE

* AT 655 PM CDT DOPPLER RADAR INDICATED A SEVERE STORM WITH LARGE
  HAIL 25 MILES SOUTH OF MENOMONIE.  THE STORM WAS MOVRING
  SOUTHEAST AT 20 MPH.

THIS IS A DANGEROUS STORM...WITH LARGE HAIL.  STAY INDOORS AWAY
FROM WINDOWS.


SCOTT

The office that day

Everything else NWS Twin Cities, MN issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 1, 4:22 PM CDTSevere Thunderstorm WarningMPXRusk53 min
Sep 1, 5:09 PM CDTSevere Thunderstorm WarningMPXBarron, Polk66 min
Sep 1, 5:12 PM CDTSevere Thunderstorm WarningMPXRusk48 min

Nearby

Severe Thunderstorm Warnings in Wisconsin, 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.