Alert archive / Wisconsin / Tornado Watches in 2018
Tornado Watch 405
The Storm Prediction Center issued this tornado watch at Oct 9, 2018, 5:09 PM CDT for Allamakee County, Clayton County, Fayette County, Iowa; 14 counties in Wisconsin. It was in force for 4 hr.
The area
The outline as issued.
The facts
- Issued
- Oct 9, 2018, 5:09 PM CDT (22:09 UTC)
- Expired
- Oct 9, 2018, 9:08 PM CDT
- In force
- 4 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1 in
- Strongest gust expected
- 55 kt
Counties Allamakee County, IA, Clayton County, IA, Fayette County, IA, Adams County, WI, Columbia County, WI, Crawford County, WI, Grant County, WI, Green Lake County, WI, Iowa County, WI, Juneau County, WI, Marquette County, WI, Monroe County, WI, Richland County, WI, Sauk County, WI, Vernon County, WI, Waushara County, WI, Winnebago County, WI
The radar
The La Crosse radar (KARX), 97 km from the middle of the area, began a volume at 22:10 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 SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 40%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 20%
- Ten or more severe hail reports
- 5%
- One or more hailstones of 2 inches or more
- 5%
- Six or more combined severe hail and wind reports
- 40%
Warnings issued inside it
4 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 9, 5:12 PM CDT | Severe Thunderstorm Warning | GRB | Waushara | 48 min |
| Oct 9, 5:54 PM CDT | Severe Thunderstorm Warning | GRB | Waushara, Winnebago | 51 min |
| Oct 9, 6:14 PM CDT | Severe Thunderstorm Warning | MKX | Columbia, Dane, Dodge | 46 min |
| Oct 9, 6:52 PM CDT | Severe Thunderstorm Warning | MKX | Fond du Lac, Green Lake | 38 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Green Bay/Straub, WI (KGRB), launched 12:00Z, 10.2 hours before the alert went out and 196 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
- 70 J/kg
- Mixed-layer CIN
- -125 J/kg
- Mixed-layer LCL
- 986 m above ground
- 0-6 km bulk shear
- 44 kt
- 0-1 km storm-relative helicity
- 133 m²/s²
- 0-3 km storm-relative helicity
- 163 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.0
The text
As transmitted.
213 WWUS20 KWNS 092207 SEL5 SPC WW 092207 IAZ000-WIZ000-100300- URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 405 NWS Storm Prediction Center Norman OK 510 PM CDT Tue Oct 9 2018 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Extreme northeastern Iowa Parts of southwestern and central Wisconsin * Effective this Tuesday afternoon and evening from 510 PM until 1000 PM CDT. * Primary threats include... A couple tornadoes possible Isolated damaging wind gusts to 65 mph possible SUMMARY...Small warm sector supercells should persist for several hours to the east and south of a slow-moving front. The storm environment is sufficient for storms with a couple of tornadoes, and perhaps isolated strong outflow gusts. The tornado watch area is approximately along and 55 statute miles east and west of a line from 40 miles west northwest of Oshkosh WI to 30 miles east southeast of Waterloo IA. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU5). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. && OTHER WATCH INFORMATION...CONTINUE...WW 403...WW 404... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 55 knots. A few cumulonimbi with maximum tops to 450. Mean storm motion vector 22025. ...Thompson
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 8, 7:03 PM CDT | Mesoscale Discussion | SPC | Appanoose, Clarke, Dallas, Decatur, Jasper, Lucas and 9 more | 57 min |
| Oct 9, 12:59 PM CDT | Mesoscale Discussion | SPC | Appanoose, Benton, Buchanan, Clarke, Davis, Decatur and 19 more | 3 hr |
| Oct 9, 1:46 PM CDT | Tornado Watch | SPC | Adair, Adams, Appanoose, Benton, Black Hawk, Boone and 36 more | 7 hr |
| Oct 9, 2:45 PM CDT | Mesoscale Discussion | SPC | Cedar, Clinton, Dubuque, Jackson, Jones, Muscatine and 1 more | 2 hr |
| Oct 9, 3:53 PM CDT | Mesoscale Discussion | SPC | Appanoose, Benton, Black Hawk, Boone, Buchanan, Clarke and 29 more | 2 hr |
| Oct 9, 6:37 PM CDT | Mesoscale Discussion | SPC | Allamakee, Appanoose, Benton, Black Hawk, Bremer, Buchanan and 21 more | 83 min |
Nearby
Tornado Watches in Wisconsin, 2018Tornado Watches in Iowa, 2018Every tornado watch in 2018
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.