Alert archive / Minnesota / Severe Thunderstorm Watches in 2018
Severe Thunderstorm Watch 274
The Storm Prediction Center issued this severe thunderstorm watch at Jul 12, 2018, 5:04 PM CDT for Lyon County, Osceola County, Sioux County, Iowa; 36 counties in Minnesota; 14 counties in Wisconsin. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 12, 2018, 5:04 PM CDT (22:04 UTC)
- Expired
- Jul 13, 2018, 12:00 AM CDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 53 counties
Lyon County, IA, Osceola County, IA, Sioux County, IA, Anoka County, MN, Blue Earth County, MN, Brown County, MN, Carver County, MN, Chisago County, MN, Cottonwood County, MN, Dakota County, MN, Dodge County, MN, Faribault County, MN, Freeborn County, MN, Goodhue County, MN, Hennepin County, MN, Jackson County, MN, Le Sueur County, MN, Lincoln County, MN, Lyon County, MN, Martin County, MN, McLeod County, MN, Murray County, MN, Nicollet County, MN, Nobles County, MN, Olmsted County, MN, Pipestone County, MN, Ramsey County, MN, Redwood County, MN, Renville County, MN, Rice County, MN, Rock County, MN, Scott County, MN, Sibley County, MN, Steele County, MN, Wabasha County, MN, Waseca County, MN, Washington County, MN, Watonwan County, MN, Winona County, MN, Barron County, WI, Buffalo County, WI, Chippewa County, WI, Clark County, WI, Dunn County, WI, Eau Claire County, WI, Jackson County, WI, Pepin County, WI, Pierce County, WI, Polk County, WI, Rusk County, WI, Saint Croix County, WI, Taylor County, WI, Trempealeau County, WI
The radar
The Minneapolis radar (KMPX), 70 km from the middle of the area, began a volume at 22:04 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
- 5%
- One or more EF2 to EF5 tornadoes
- 2%
- Ten or more severe wind reports
- 50%
- One or more gusts of 65 knots or more
- 20%
- Ten or more severe hail reports
- 40%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 80%
Warnings issued inside it
18 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 12, 5:08 PM CDT | Severe Thunderstorm Warning | FSD | Pipestone, Rock | 52 min |
| Jul 12, 5:18 PM CDT | Severe Thunderstorm Warning | MPX | Chisago, Washington | 27 min |
| Jul 12, 5:27 PM CDT | Severe Thunderstorm Warning | MPX | Carver, Hennepin | 33 min |
| Jul 12, 5:35 PM CDT | Flash Flood Warning | FSD | Lincoln, Lyon, Murray, Pipestone | 3 hr |
| Jul 12, 5:42 PM CDT | Severe Thunderstorm Warning | FSD | Murray, Pipestone | 33 min |
| Jul 12, 5:43 PM CDT | Severe Thunderstorm Warning | MPX | Carver, Scott | 47 min |
| Jul 12, 6:02 PM CDT | Severe Thunderstorm Warning | MPX | Dakota, Hennepin | 43 min |
| Jul 12, 6:44 PM CDT | Severe Thunderstorm Warning | MPX | Barron, Chippewa, Rusk | 46 min |
| Jul 12, 6:47 PM CDT | Severe Thunderstorm Warning | MPX | Dakota | 31 min |
| Jul 12, 6:57 PM CDT | Flash Flood Warning | MPX | Barron | 3 hr |
| Jul 12, 7:06 PM CDT | Severe Thunderstorm Warning | MPX | Goodhue | 54 min |
| Jul 12, 7:27 PM CDT | Severe Thunderstorm Warning | MPX | Chippewa, Eau Claire, Rusk | 48 min |
| Jul 12, 7:38 PM CDT | Severe Thunderstorm Warning | ARX | Buffalo, Clark, Jackson, Trempealeau | 52 min |
| Jul 12, 7:43 PM CDT | Severe Thunderstorm Warning | ARX | Clark, Taylor | 62 min |
| Jul 12, 8:12 PM CDT | Severe Thunderstorm Warning | MPX | Goodhue | 33 min |
| Jul 12, 8:32 PM CDT | Severe Thunderstorm Warning | ARX | Clark, Jackson, La Crosse, Monroe, Trempealeau | 43 min |
| Jul 12, 8:39 PM CDT | Severe Thunderstorm Warning | ARX | Clark, Taylor | 36 min |
| Jul 12, 8:49 PM CDT | Severe Thunderstorm Warning | ARX | Wabasha | 41 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
Minneapolis, MN (KMPX), launched 12:00Z, 10.1 hours before the alert went out and 68 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
- 745 J/kg
- Mixed-layer CIN
- -244 J/kg
- Mixed-layer LCL
- 1291 m above ground
- 0-6 km bulk shear
- 29 kt
- 0-1 km storm-relative helicity
- 387 m²/s²
- 0-3 km storm-relative helicity
- 437 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 3.3
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 11, 8:58 PM CDT | Mesoscale Discussion | SPC | Aitkin, Becker, Beltrami, Cass, Clay, Clearwater and 12 more | 2 hr |
| Jul 11, 11:42 PM CDT | Mesoscale Discussion | SPC | Aitkin, Becker, Carlton, Cass, Crow Wing, Hubbard and 10 more | 2 hr |
| Jul 12, 12:57 AM CDT | Severe Thunderstorm Watch | SPC | Aitkin, Carlton, Cass, Crow Wing, Itasca, Lake and 2 more | 6 hr |
| Jul 12, 4:47 PM CDT | Mesoscale Discussion | SPC | Anoka, Blue Earth, Brown, Carver, Cottonwood, Dakota and 31 more | 88 min |
Nearby
Severe Thunderstorm Watches in Minnesota, 2018Severe Thunderstorm Watches in Wisconsin, 2018Severe Thunderstorm Watches in Iowa, 2018Every severe thunderstorm 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.