Alert archive / Wisconsin / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 185, NWS Twin Cities, MN

August 3, 1997Polk County, Wisconsin

NWS Twin Cities, MN issued this severe thunderstorm warning at Aug 3, 1997, 8:13 PM CDT for Polk County, Wisconsin. It was in force for 47 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
Aug 3, 1997, 8:13 PM CDT (01:13 UTC)
Expired
Aug 3, 1997, 9:00 PM CDT
In force
47 min
Issued by
NWS Twin Cities, MN
Area
Whole counties

County Polk County, WI

The radar

The Minneapolis radar (KMPX), 111 km from the middle of the area, began a volume at 01:12 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
Aug 3, 8:35 PM CDTThunderstorm Wind 55Luck, WITrees and powerlines down. Estimated windspeed.
Aug 3, 8:35 PM CDTThunderstorm Wind 55Frederic, WIPower lines down. 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 nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 1.2 hours before the alert went out and 113 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 00:00Z on 1997-08-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1028 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 00:00Z on 1997-08-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 4 square meters per square second.1939587897Sfc1 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
1028 J/kg
Mixed-layer CIN
-14 J/kg
Mixed-layer LCL
1282 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
4 m²/s²
0-3 km storm-relative helicity
71 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.6

Open this sounding in Storm Lab

The text

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

872 
WUUS1 KMSP 040114 RRA
SVRMSP
WIC095-040200-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
813 PM CDT SUN AUG 3 1997

* SEVERE THUNDERSTORM WARNING FOR
  NORTHERN POLK COUNTY - NORTHWESTERN WISCONSIN

* UNTIL 900 PM CDT
 
* SOME LOCATIONS AFFECTED
    FREDERIC
    LUCK
    ATLAS
    MILLTOWN

* AT 810 PM CDT DOPPLER RADAR INDICATED A SEVERE STORM WITH LARGE
  HAIL 5 MILES NORTH OF GRANTSBURG OR ABOUT OR ABOUT 40
  MILES NORTHWEST OF RICE LAKE. THE STORM WAS MOVING SOUTHEAST AT
  35 MPH.

DAMAGING WINDS AND LARGE HAIL ARE LIKELY.  GO INSIDE A STURDY
BUILDING AND STAY AWAY FROM WINDOWS.

MBK

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 3, 8:42 PM CDTSevere Thunderstorm WarningMPXPolk48 min
Aug 3, 9:10 PM CDTSevere Thunderstorm WarningMPXBarron, Dunn, Saint Croix60 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.