Alert archive / Illinois / Tornado Watches in 2020
Tornado Watch 505
The Storm Prediction Center issued this tornado watch at Nov 10, 2020, 2:05 PM CST for 31 counties in Illinois; 11 counties in Wisconsin. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Nov 10, 2020, 2:05 PM CST (20:05 UTC)
- Expired
- Nov 10, 2020, 8:00 PM CST
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1 in
- Strongest gust expected
- 65 kt
All 42 counties
Boone County, IL, Bureau County, IL, Carroll County, IL, Cook County, IL, DeKalb County, IL, DuPage County, IL, Ford County, IL, Fulton County, IL, Grundy County, IL, Henry County, IL, Iroquois County, IL, Jo Daviess County, IL, Kane County, IL, Kankakee County, IL, Kendall County, IL, Knox County, IL, Lake County, IL, LaSalle County, IL, Lee County, IL, Livingston County, IL, Marshall County, IL, McHenry County, IL, Ogle County, IL, Peoria County, IL, Putnam County, IL, Rock Island County, IL, Stark County, IL, Stephenson County, IL, Whiteside County, IL, Will County, IL, Winnebago County, IL, Dane County, WI, Green County, WI, Jefferson County, WI, Kenosha County, WI, Milwaukee County, WI, Ozaukee County, WI, Racine County, WI, Rock County, WI, Walworth County, WI, Washington County, WI, Waukesha County, WI
The radar
The Quad Cities radar (KDVN), 104 km from the middle of the area, began a volume at 20:06 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
- 60%
- One or more gusts of 65 knots or more
- 30%
- 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
- 70%
Warnings issued inside it
30 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Nov 10, 2:07 PM CST | Severe Thunderstorm Warning | DVN | Henry, Rock Island, Whiteside | 38 min |
| Nov 10, 2:11 PM CST | Severe Thunderstorm Warning | DVN | Henry, McDonough, Mercer, Warren | 34 min |
| Nov 10, 2:23 PM CST | Tornado Warning | DVN | Henry, Rock Island, Whiteside | 17 min |
| Nov 10, 2:38 PM CST | Severe Thunderstorm Warning | DVN | Carroll, Whiteside | 52 min |
| Nov 10, 2:40 PM CST | Severe Thunderstorm Warning | DVN | Bureau, Henry | 50 min |
| Nov 10, 2:41 PM CST | Severe Thunderstorm Warning | ILX | Fulton, Knox, Mason, Peoria, Stark, Tazewell | 49 min |
| Nov 10, 2:48 PM CST | Severe Thunderstorm Warning | LOT | Lee, Ogle | 72 min |
| Nov 10, 2:51 PM CST | Tornado Warning | ILX | Fulton, Knox, Peoria | 24 min |
| Nov 10, 2:54 PM CST | Tornado Warning | DVN | Carroll, Whiteside | 19 min |
| Nov 10, 3:19 PM CST | Severe Thunderstorm Warning | DVN | Stephenson | 24 min |
| Nov 10, 3:20 PM CST | Severe Thunderstorm Warning | LOT | Boone, DeKalb, Lee, Ogle, Winnebago | 70 min |
| Nov 10, 3:21 PM CST | Severe Thunderstorm Warning | DVN | Bureau, Putnam | 39 min |
| Nov 10, 3:25 PM CST | Severe Thunderstorm Warning | ILX | Fulton, Knox, Marshall, Mason, Peoria, Stark and 2 more | 50 min |
| Nov 10, 3:37 PM CST | Tornado Warning | DVN | Bureau, Putnam | 20 min |
| Nov 10, 3:38 PM CST | Severe Thunderstorm Warning | MKX | Rock, Walworth | 82 min |
| Nov 10, 3:45 PM CST | Tornado Warning | ILX | Marshall | 15 min |
| Nov 10, 3:48 PM CST | Severe Thunderstorm Warning | LOT | LaSalle | 57 min |
| Nov 10, 3:50 PM CST | Severe Thunderstorm Warning | LOT | Kane, McHenry | 55 min |
| Nov 10, 3:57 PM CST | Severe Thunderstorm Warning | DVN | Bureau, Putnam | 18 min |
| Nov 10, 4:08 PM CST | Severe Thunderstorm Warning | ILX | McLean, Marshall, Tazewell, Woodford | 52 min |
| Nov 10, 4:10 PM CST | Severe Thunderstorm Warning | LOT | DeKalb, Kane, Kendall | 80 min |
| Nov 10, 4:16 PM CST | Severe Thunderstorm Warning | MKX | Kenosha, Racine | 74 min |
| Nov 10, 4:17 PM CST | Severe Thunderstorm Warning | MKX | Jefferson, Waukesha | 44 min |
| Nov 10, 4:18 PM CST | Tornado Warning | LOT | LaSalle | 27 min |
| Nov 10, 4:21 PM CST | Tornado Warning | MKX | Racine, Walworth | 24 min |
| Nov 10, 4:34 PM CST | Severe Thunderstorm Warning | LOT | Grundy, LaSalle, Livingston | 71 min |
| Nov 10, 4:35 PM CST | Severe Thunderstorm Warning | MKX | Milwaukee | 38 min |
| Nov 10, 4:38 PM CST | Severe Thunderstorm Warning | LOT | Cook, DuPage, Lake, McHenry | 82 min |
| Nov 10, 4:54 PM CST | Severe Thunderstorm Warning | LOT | Cook, Will | 81 min |
| Nov 10, 5:10 PM CST | Tornado Warning | MKX | Kenosha | 20 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 12:00Z, 8.1 hours before the alert went out and 97 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
- 97 J/kg
- Mixed-layer CIN
- -91 J/kg
- Mixed-layer LCL
- 614 m above ground
- 0-6 km bulk shear
- 52 kt
- 0-1 km storm-relative helicity
- 192 m²/s²
- 0-3 km storm-relative helicity
- 173 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Nov 10, 8:52 AM CST | Mesoscale Discussion | SPC | Adams, Brown, Cass, Fulton, Hancock, McDonough and 2 more | 113 min |
| Nov 10, 11:22 AM CST | Severe Thunderstorm Watch | SPC | Adams, Brown, Bureau, Calhoun, Carroll, Cass and 29 more | 7 hr |
| Nov 10, 1:28 PM CST | Mesoscale Discussion | SPC | Boone, Cook, DeKalb, DuPage, Ford, Grundy and 12 more | 92 min |
| Nov 10, 1:48 PM CST | Mesoscale Discussion | SPC | Adams, Brown, Bureau, Calhoun, Carroll, Cass and 34 more | 87 min |
| Nov 10, 3:30 PM CST | Mesoscale Discussion | SPC | Boone, Lee, McHenry, Ogle, Winnebago | 2 hr |
| Nov 10, 5:01 PM CST | Mesoscale Discussion | SPC | Bond, Champaign, Christian, Clark, Clay, Clinton and 26 more | 119 min |
| Nov 10, 5:03 PM CST | Mesoscale Discussion | SPC | Cook, DuPage, Grundy, Iroquois, Kankakee, Lake and 2 more | 57 min |
| Nov 10, 9:19 AM CST | Mesoscale Discussion | SPC | Barron, Dunn, Pierce, Rusk, Saint Croix, Sawyer | 5 hr |
| Nov 10, 3:51 PM CST | Mesoscale Discussion | SPC | Burnett, Polk, Saint Croix | 6 hr |
Nearby
Tornado Watches in Illinois, 2020Tornado Watches in Wisconsin, 2020Every tornado watch in 2020
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.