Alert archive / Iowa / Severe Thunderstorm Watches in 2017
Severe Thunderstorm Watch 342
The Storm Prediction Center issued this severe thunderstorm watch at Jun 16, 2017, 10:25 PM CDT for 15 counties in Illinois; 16 counties in Iowa; 11 counties in Wisconsin. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Jun 16, 2017, 10:25 PM CDT (03:25 UTC)
- Expired
- Jun 17, 2017, 3:34 AM CDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 42 counties
Benton County, IA, Buchanan County, IA, Cedar County, IA, Clinton County, IA, Delaware County, IA, Dubuque County, IA, Iowa County, IA, Jackson County, IA, Johnson County, IA, Jones County, IA, Keokuk County, IA, Linn County, IA, Louisa County, IA, Muscatine County, IA, Scott County, IA, Washington County, IA, Boone County, IL, Bureau County, IL, Carroll County, IL, DeKalb County, IL, Henry County, IL, Jo Daviess County, IL, Lee County, IL, McHenry County, IL, Mercer County, IL, Ogle County, IL, Putnam County, IL, Rock Island County, IL, Stephenson County, IL, Whiteside County, IL, Winnebago County, IL, Dane County, WI, Green County, WI, Iowa County, WI, Jefferson County, WI, Kenosha County, WI, Lafayette County, WI, Milwaukee County, WI, Racine County, WI, Rock County, WI, Walworth County, WI, Waukesha County, WI
The radar
The Quad Cities radar (KDVN), 114 km from the middle of the area, began a volume at 03:27 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
- 10%
- One or more EF2 to EF5 tornadoes
- 5%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 10%
- 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
- 70%
Warnings issued inside it
3 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 16, 10:32 PM CDT | Severe Thunderstorm Warning | MKX | Iowa, Lafayette | 43 min |
| Jun 16, 10:45 PM CDT | Severe Thunderstorm Warning | MKX | Dane, Jefferson, Rock | 45 min |
| Jun 16, 11:23 PM CDT | Severe Thunderstorm Warning | DVN | Benton, Linn | 45 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
Davenport, (KDVN), launched 00:00Z, 3.4 hours before the alert went out and 110 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
- 962 J/kg
- Mixed-layer CIN
- -34 J/kg
- Mixed-layer LCL
- 1772 m above ground
- 0-6 km bulk shear
- 25 kt
- 0-1 km storm-relative helicity
- 2 m²/s²
- 0-3 km storm-relative helicity
- 94 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.8
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 17, 1:35 AM CDT | Mesoscale Discussion | SPC | Boone, Bureau, Carroll, DeKalb, Henry, Jo Daviess and 15 more | 115 min |
| Jun 17, 2:44 PM CDT | Mesoscale Discussion | SPC | Adams, Boone, Bureau, Carroll, Cook, DeKalb and 32 more | 2 hr |
| Jun 17, 5:39 PM CDT | Severe Thunderstorm Watch | SPC | Adams, Boone, Brown, Bureau, Cass, Champaign and 45 more | 7 hr |
| Jun 16, 7:52 PM CDT | Severe Thunderstorm Watch | SPC | Adair, Adams, Appanoose, Audubon, Boone, Cass and 23 more | 9 hr |
| Jun 16, 9:27 PM CDT | Mesoscale Discussion | SPC | Adams, Fremont, Mills, Montgomery, Page, Ringgold and 1 more | 2 hr |
Nearby
Severe Thunderstorm Watches in Iowa, 2017Severe Thunderstorm Watches in Illinois, 2017Severe Thunderstorm Watches in Wisconsin, 2017Every severe thunderstorm watch in 2017
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.