Alert archive / Wisconsin / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 35, NWS Milwaukee, WI

June 20, 1997Green County, Wisconsin

NWS Milwaukee, WI issued this severe thunderstorm warning at Jun 20, 1997, 6:20 PM CDT for Green County, Wisconsin. It was in force for 60 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
Jun 20, 1997, 6:20 PM CDT (23:20 UTC)
Expired
Jun 20, 1997, 7:20 PM CDT
In force
60 min
Issued by
NWS Milwaukee, WI
Area
Whole counties

County Green County, WI

The radar

The Milwaukee radar (KMKX), 92 km from the middle of the area, began a volume at 23:20 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
Jun 20, 6:45 PM CDTHail 0.75Clarno, 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.

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 11.3 hours before the alert went out and 139 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, Davenport, at 12:00Z on 1997-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2894 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, Davenport, at 12:00Z on 1997-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 218 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
2894 J/kg
Mixed-layer CIN
-77 J/kg
Mixed-layer LCL
766 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
218 m²/s²
0-3 km storm-relative helicity
188 m²/s²
Significant tornado parameter
1.6
Supercell composite
12.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KMKE 202321 RRA
SVRMKE
WIC045-210020-

BULLETIN - IMMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
620 PM CDT FRI JUN 20 1997

* SEVERE THUNDERSTORM WARNING FOR
  GREEN COUNTY - SOUTH CENTRAL WISCONSIN

* UNTIL 720 PM CDT
 
* SOME LOCATIONS AFFECTED
  CLARNO                  BY 630 PM CDT
  MONROE                  BY 633 PM CDT
  TWIN GROVE              BY 641 PM CDT

* AT 617 PM CDT...DOPPLER RADAR AT SULLIVAN INDICATED A RAPIDLY
  DEVELOPING THUNDERSTORM 40 MILES WEST SOUTHWEST OF JANESVILLE OR 6
  MILES WEST OF CLARNO MOVING EAST AT 30 MPH.

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH YOU SHOULD MOVE
INSIDE A STRONG BUILDING. DO NOT STAND BY WINDOWS. DO NOT USE
TELEPHONES OR ELECTRICAL APPLIANCES UNLESS IN AN EMERGENCY UNTIL
THE STORM HAS PASSED.


TZ/MK

The office that day

Everything else NWS Milwaukee, WI issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 20, 8:34 AM CDTSevere Thunderstorm WarningMKXRock61 min
Jun 20, 6:26 PM CDTSevere Thunderstorm WarningMKXMilwaukee64 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.