Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 72, NWS Milwaukee, WI
NWS Milwaukee, WI issued this severe thunderstorm warning at Sep 7, 2021, 11:42 AM CDT for Rock County, Walworth County, Wisconsin. It was in force for 48 min. 1 report came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- Sep 7, 2021, 11:42 AM CDT (16:42 UTC)
- Expired
- Sep 7, 2021, 12:30 PM CDT
- In force
- 48 min
- Issued by
- NWS Milwaukee, WI
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 50.0 mph
Counties Rock County, WI, Walworth County, WI
The radar
The Milwaukee radar (KMKX), 34 km from the middle of the area, began a volume at 16:41 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 |
|---|---|---|---|
| Sep 7, 11:52 AM CDT | HAIL 1 | Milton, WI | REPORT FROM MPING: QUARTER (1.00 IN.). |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Sep 7, 11:21 AM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
The nearest sounding before it
Davenport, (KDVN), launched 12:00Z, 4.7 hours before the alert went out and 186 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
- 827 J/kg
- Mixed-layer CIN
- -263 J/kg
- Mixed-layer LCL
- 1475 m above ground
- 0-6 km bulk shear
- 39 kt
- 0-1 km storm-relative helicity
- 185 m²/s²
- 0-3 km storm-relative helicity
- 167 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted.
840 WUUS53 KMKX 071642 SVRMKX WIC105-127-071730- /O.NEW.KMKX.SV.W.0072.210907T1642Z-210907T1730Z/ BULLETIN - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Warning National Weather Service Milwaukee/Sullivan WI 1142 AM CDT Tue Sep 7 2021 The National Weather Service in Milwaukee/Sullivan has issued a * Severe Thunderstorm Warning for... Northern Walworth County in southeastern Wisconsin... Northern Rock County in south central Wisconsin... * Until 1230 PM CDT. * At 1141 AM CDT, severe thunderstorms were located along a line extending from near Lake Koshkonong to 6 miles southwest of Edgerton, moving east at 60 mph. HAZARD...Quarter size hail. SOURCE...Radar indicated. IMPACT...Damage to vehicles is expected. * Severe thunderstorms will be near... Milton and Lake Koshkonong around 1150 AM CDT. Whitewater around 1155 AM CDT. East Troy and Potter Lake around 1220 PM CDT. Other locations impacted by these severe thunderstorms include Indianford, Abells Corners, Tibbets, Troy Center, Leyden, Millard, La Grange, Lima Center, Richmond and Johnstown Center. PRECAUTIONARY/PREPAREDNESS ACTIONS... For your protection move to an interior room on the lowest floor of a building. && LAT...LON 4271 8928 4285 8905 4284 8831 4268 8831 TIME...MOT...LOC 1641Z 266DEG 53KT 4285 8900 4276 8915 HAIL THREAT...RADAR INDICATED MAX HAIL SIZE...1.00 IN WIND THREAT...RADAR INDICATED MAX WIND GUST...<50 MPH $$ GEHRING
1 follow-up statement
375 WWUS53 KMKX 071701 SVSMKX Severe Weather Statement National Weather Service Milwaukee/Sullivan WI 1201 PM CDT Tue Sep 7 2021 WIC105-127-071730- /O.CON.KMKX.SV.W.0072.000000T0000Z-210907T1730Z/ Walworth WI-Rock WI- 1201 PM CDT Tue Sep 7 2021 ...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1230 PM CDT FOR NORTHERN WALWORTH AND NORTHEASTERN ROCK COUNTIES... At 1200 PM CDT, severe thunderstorms were located along a line extending from near Whitewater to 6 miles east of Milton, moving east at 55 mph. HAZARD...Quarter size hail. SOURCE...Trained weather spotters. IMPACT...Damage to vehicles is expected. These severe storms will be near... East Troy around 1220 PM CDT. Potter Lake around 1225 PM CDT. Other locations impacted by these severe thunderstorms include Johnstown Center, Abells Corners, Tibbets, Troy Center, Millard, La Grange, Lima Center, Richmond and Burlington. PRECAUTIONARY/PREPAREDNESS ACTIONS... For your protection move to an interior room on the lowest floor of a building. && LAT...LON 4270 8906 4284 8881 4284 8831 4268 8831 TIME...MOT...LOC 1700Z 266DEG 53KT 4287 8867 4278 8882 HAIL THREAT...OBSERVED MAX HAIL SIZE...1.00 IN WIND THREAT...RADAR INDICATED MAX WIND GUST...<50 MPH $$ GEHRING
The office that day
Everything else NWS Milwaukee, WI issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 6, 9:06 PM CDT | Small Craft Advisory | MKX | 45 hr | |
| Sep 7, 2:21 AM CDT | Gale Warning | MKX | 13 hr | |
| Sep 7, 8:41 AM CDT | Special Weather Statement | MKX | Marquette | 49 min |
| Sep 7, 8:57 AM CDT | Severe Thunderstorm Warning | MKX | Green Lake, Marquette | 48 min |
| Sep 7, 9:34 AM CDT | Severe Thunderstorm Warning | MKX | Fond du Lac | 56 min |
| Sep 7, 10:10 AM CDT | Severe Thunderstorm Warning | MKX | Fond du Lac | 50 min |
| Sep 7, 10:27 AM CDT | Severe Thunderstorm Warning | MKX | Fond du Lac, Sheboygan | 78 min |
| Sep 7, 10:40 AM CDT | Special Weather Statement | MKX | Columbia, Dane, Dodge, Iowa | 65 min |
| Sep 7, 10:57 AM CDT | Special Marine Warning | MKX | 63 min | |
| Sep 7, 11:01 AM CDT | Severe Thunderstorm Warning | MKX | Columbia, Dane, Dodge, Jefferson | 59 min |
| Sep 7, 11:04 AM CDT | Severe Thunderstorm Warning | MKX | Dodge, Fond du Lac, Ozaukee, Sheboygan, Washington | 56 min |
| Sep 7, 11:11 AM CDT | Severe Thunderstorm Warning | MKX | Green, Rock | 34 min |
| Sep 7, 11:22 AM CDT | Special Marine Warning | MKX | 53 min | |
| Sep 7, 11:27 AM CDT | Severe Thunderstorm Warning | MKX | Milwaukee, Ozaukee, Washington, Waukesha | 48 min |
| Sep 7, 11:31 AM CDT | Special Marine Warning | MKX | 89 min | |
| Sep 7, 11:45 AM CDT | Severe Thunderstorm Warning | MKX | Jefferson, Milwaukee, Waukesha | 60 min |
| Sep 7, 12:18 PM CDT | Special Marine Warning | MKX | 87 min | |
| Sep 7, 12:19 PM CDT | Severe Thunderstorm Warning | MKX | Racine, Walworth | 40 min |
| Sep 7, 12:30 PM CDT | Severe Thunderstorm Warning | MKX | Kenosha, Racine, Rock, Walworth | 60 min |
| Sep 7, 12:47 PM CDT | Special Weather Statement | MKX | Milwaukee | 28 min |
Nearby
Severe Thunderstorm Warnings in Wisconsin, 2021Every severe thunderstorm warning in 2021
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.