Alert archive / Illinois / Severe Thunderstorm Watches in 2018
Severe Thunderstorm Watch 286
The Storm Prediction Center issued this severe thunderstorm watch at Jul 19, 2018, 6:49 PM CDT for 32 counties in Illinois; 10 counties in Missouri. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 19, 2018, 6:49 PM CDT (23:49 UTC)
- Expired
- Jul 20, 2018, 2:00 AM CDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
All 42 counties
Adams County, IL, Bond County, IL, Brown County, IL, Calhoun County, IL, Cass County, IL, Christian County, IL, Clay County, IL, Clinton County, IL, Cumberland County, IL, Effingham County, IL, Fayette County, IL, Fulton County, IL, Greene County, IL, Hancock County, IL, Jasper County, IL, Jersey County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Mason County, IL, McDonough County, IL, Menard County, IL, Montgomery County, IL, Morgan County, IL, Pike County, IL, Richland County, IL, Saint Clair County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Shelby County, IL, Washington County, IL, City of Saint Louis, MO, Knox County, MO, Lewis County, MO, Lincoln County, MO, Marion County, MO, Pike County, MO, Ralls County, MO, Saint Charles County, MO, Saint Louis County, MO, Shelby County, MO
The radar
The Lincoln radar (KILX), 97 km from the middle of the area, began a volume at 23:50 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
- 20%
- One or more EF2 to EF5 tornadoes
- 5%
- 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
- 20%
- Six or more combined severe hail and wind reports
- 80%
Warnings issued inside it
17 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 19, 7:00 PM CDT | Severe Thunderstorm Warning | DVN | Hancock | 45 min |
| Jul 19, 7:04 PM CDT | Severe Thunderstorm Warning | LSX | Adams | 56 min |
| Jul 19, 7:12 PM CDT | Severe Thunderstorm Warning | LSX | Knox, Lewis | 48 min |
| Jul 19, 7:26 PM CDT | Tornado Warning | LSX | Adams | 37 min |
| Jul 19, 7:53 PM CDT | Severe Thunderstorm Warning | LSX | Adams, Brown, Pike | 67 min |
| Jul 19, 7:56 PM CDT | Severe Thunderstorm Warning | LSX | Adams, Pike | 64 min |
| Jul 19, 8:32 PM CDT | Severe Thunderstorm Warning | ILX | Scott | 43 min |
| Jul 19, 8:54 PM CDT | Severe Thunderstorm Warning | LSX | Calhoun, Greene, Pike | 66 min |
| Jul 19, 8:58 PM CDT | Severe Thunderstorm Warning | LSX | Adams, Pike | 62 min |
| Jul 19, 9:13 PM CDT | Severe Thunderstorm Warning | ILX | Scott | 22 min |
| Jul 19, 9:38 PM CDT | Severe Thunderstorm Warning | LSX | Greene, Jersey | 52 min |
| Jul 19, 9:41 PM CDT | Severe Thunderstorm Warning | LSX | Calhoun, Greene, Pike | 49 min |
| Jul 19, 10:19 PM CDT | Severe Thunderstorm Warning | LSX | Calhoun, Greene, Jersey, Macoupin, Madison | 41 min |
| Jul 19, 10:46 PM CDT | Severe Thunderstorm Warning | ILX | Christian | 44 min |
| Jul 19, 11:23 PM CDT | Severe Thunderstorm Warning | ILX | Christian, Shelby | 52 min |
| Jul 20, 12:11 AM CDT | Tornado Warning | LSX | Fayette, Marion | 34 min |
| Jul 20, 12:21 AM CDT | Severe Thunderstorm Warning | LSX | Clinton, Marion | 39 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, 11.8 hours before the alert went out and 205 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1807 m above ground
- 0-6 km bulk shear
- 13 kt
- 0-1 km storm-relative helicity
- -12 m²/s²
- 0-3 km storm-relative helicity
- -21 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 |
|---|---|---|---|---|
| Jul 19, 5:18 PM CDT | Mesoscale Discussion | SPC | Hancock, Henderson, McDonough, Mercer, Rock Island, Warren | 57 min |
| Jul 19, 6:26 PM CDT | Mesoscale Discussion | SPC | Adams, Bond, Brown, Calhoun, Cass, Christian and 31 more | 64 min |
| Jul 19, 12:47 AM CDT | Mesoscale Discussion | SPC | Atchison, Holt | 118 min |
| Jul 19, 1:00 AM CDT | Severe Thunderstorm Watch | SPC | Andrew, Atchison, Buchanan, Holt, Nodaway | 5 hr |
| Jul 19, 3:52 AM CDT | Mesoscale Discussion | SPC | Atchison, Holt | 53 min |
| Jul 19, 9:58 AM CDT | Mesoscale Discussion | SPC | Andrew, Bates, Benton, Boone, Caldwell, Callaway and 45 more | 2 hr |
| Jul 19, 11:22 AM CDT | Severe Thunderstorm Watch | SPC | Barry, Barton, Bates, Benton, Caldwell, Callaway and 47 more | 10 hr |
| Jul 19, 12:26 PM CDT | Severe Thunderstorm Watch | SPC | Platte | 8 hr |
| Jul 19, 2:15 PM CDT | Mesoscale Discussion | SPC | Bollinger, Butler, Carter, Christian, Dallas, Dent and 27 more | 2 hr |
| Jul 19, 2:32 PM CDT | Mesoscale Discussion | SPC | Mercer, Putnam, Schuyler | 118 min |
| Jul 19, 2:43 PM CDT | Mesoscale Discussion | SPC | Platte | 92 min |
| Jul 19, 3:11 PM CDT | Tornado Watch | SPC | Clark, Scotland | 6 hr |
Nearby
Severe Thunderstorm Watches in Illinois, 2018Severe Thunderstorm Watches in Missouri, 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.