Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 93, NWS Milwaukee, WI

October 23, 2001Walworth County, Wisconsin

NWS Milwaukee, WI issued this severe thunderstorm warning at Oct 23, 2001, 11:02 PM CDT for Walworth 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: Oct 23, 2001, 11:02 PM CDT (04:02 UTC)
Expired: Oct 24, 2001, 12:00 AM CDT
In force: 58 min
Issued by: NWS Milwaukee, WI
Area: Whole counties

County Walworth County, WI

The radar

The Milwaukee radar (KMKX), 33 km from the middle of the area, began a volume at 04:03 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
Oct 23, 11:05 PM CDT	Hail 1.75	Darien, WI
Oct 24, 12:00 AM CDT	Hail 1	Lyons, 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 00:00Z, 4.0 hours before the alert went out and 199 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 542 J/kg
Mixed-layer CIN: -97 J/kg
Mixed-layer LCL: 748 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 115 m²/s²
0-3 km storm-relative helicity: 244 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 1.0

Open this sounding in Storm Lab

The text

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

942 
WUUS53 KMKX 240403
SVRMKE
WIC127-240500-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MILWAUKEE-SULLIVAN WI
1102 PM CDT TUE OCT 23 2001

THE NATIONAL WEATHER SERVICE IN SULLIVAN HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WALWORTH COUNTY IN SOUTHEAST WISCONSIN

* UNTIL MIDNIGHT CDT

* AT 1102 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 15 MILES WEST OF DARIEN...OR ABOUT 2 MILES EAST
  OF JANESVILLE...MOVING EAST AT 30 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  DARIEN AT 1120 PM CDT.
  DELAVAN AT 1125 PM CDT.
  WILLIAMS BAY AT 1130 PM CDT.
  ELKHORN AT 1135 PM CDT.

IF YOU ARE IN THE PATH OF THIS STORM...YOU SHOULD PREPARE FOR
DAMAGING WINDS IN EXCESS OF 60 MPH...LARGE HAIL...AND DEADLY
LIGHTNING. SEEK SHELTER IMMEDIATELY

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 Milwaukee, WI wrote its last area forecast discussion before this severe thunderstorm warning went out at Oct 23, 3:30 PM CDT, 7 hours 32 minutes earlier.

Area forecast discussion, Oct 23, 3:30 PM CDT, 7 hours 32 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
330 PM CDT TUE OCT 23 2001

FCST FOCUS ON PRECIP CHANCES AND SURGE OF CAA.

SFC ANALYSES HAVE BEEN SHOWING A CONSISTENT 3-4 MB FALLS ACROSS SD
TODAY AS SHORT WAVE TROUGH TRACKS ACROSS MT. AS LOW APPROACHES WI BY
12Z A 25-30 KT LLJ WILL SET UP OVER SRN WI WITH SOME THETAE ADVECTION
INTO CWA. NOT NEARLY AS STRONG AS LAST NIGHT AND LESS MOISTURE SO
CHANCE POPS WILL COVER IT.

MODELS CONTINUE TO SHOW BOMBOGENSIS OVER NRN GRTLKS AND CANADA WED
NT. BEFOREHAND...UPPER TROUGH WILL DIG SEWD TONIGHT AND THEN LIFT
NEWD ON WED VIA A 120 KT JET. WITH CYCLOGENSIS CONTINUING AND
CONTINUED CAA INTO UPPER TROUGH...THE UPPER TROUGH WILL BECOME
NEGATIVE TILT WITH MAIN VORT MAX TRACKING ACROSS EITHER NRN IL OR SRN
WI. AS INCREASING DIFF CVA AND LT FNT QUAD OF JET CATCHES UP
TO FRONT...WIDESPREAD PRECIP SHOULD DEVELOP VIA MODEL QPF. THE
CATCHING UP OF THE UPPER TROUGH TO THE FRONT SHOULD OCCUR IN TIME FOR
LIKELY TO CATEGORICAL POPS ACROSS CWA. CATEGORICAL POPS IN EAST WHERE
CONFIDENCE IS HIGH AND 60 POPS IN WEST WHERE MORE UNCERTAINTY LIES.

STRONG COLD FRONT WILL MOVE ACROSS CWA WED AFT...BUT STRONGEST CAA
TO OCCUR WED NT AS BOMBOGENESIS OCCURS IN SRN CANADA. WINDY
CONDITIONS WILL DEVELOP AND THICKNESSES WILL DROP TO 531 DM BY THU
MORNING. WITH A MOIST BL COMBINED WITH CYCLONIC FLOW AND EXPECTED
ROUNDS OF WK VORT LOBES AND SFC TROFS PASSING THROUGH CWA...30 POPS
ARE WARRANTED FROM WED NT THROUGH FRI. EXPECT A MIX OF RAIN AND
SNOW SHOWERS. GUIDANCE TEMPS LOOK GOOD BUT A LITTLE TOO WARM ON FRI
IN THE EAST.

.MKX...NONE.

MG

The office that day

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

Issued	Product	Office	Counties	Lasted
Oct 23, 9:31 PM CDT	Severe Thunderstorm Warning	MKX	Green	59 min
Oct 23, 9:58 PM CDT	Severe Thunderstorm Warning	MKX	Rock	62 min
Oct 23, 10:26 PM CDT	Severe Thunderstorm Warning	MKX	Green	49 min
Oct 23, 10:45 PM CDT	Tornado Warning	MKX	Rock	60 min
Oct 23, 11:57 PM CDT	Severe Thunderstorm Warning	MKX	Kenosha, Racine, Walworth	63 min

Nearby

Severe Thunderstorm Warnings in Wisconsin, 2001 Every severe thunderstorm warning in 2001

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.