Alert archive / Missouri / Severe Thunderstorm Watches in 2026
Severe Thunderstorm Watch 21
The Storm Prediction Center issued this severe thunderstorm watch at Mar 6, 2026, 10:28 PM CST for 6 counties in Illinois; 18 counties in Missouri. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Mar 6, 2026, 10:28 PM CST (04:28 UTC)
- Expired
- Mar 7, 2026, 3:28 AM CST
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
All 24 counties
Calhoun County, IL, Jersey County, IL, Madison County, IL, Monroe County, IL, Randolph County, IL, Saint Clair County, IL, Audrain County, MO, Boone County, MO, Callaway County, MO, City of Saint Louis, MO, Crawford County, MO, Franklin County, MO, Gasconade County, MO, Jefferson County, MO, Lincoln County, MO, Montgomery County, MO, Osage County, MO, Pike County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Warren County, MO, Washington County, MO
The radar
The St Louis radar (KLSX), 33 km from the middle of the area, began a volume at 04:32 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
- 60%
- 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
- 90%
Warnings issued inside it
1 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 7, 2:31 AM CST | Severe Thunderstorm Warning | LSX | Boone, Callaway | 19 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
Lincoln, IL (KILX), launched 00:00Z, 4.5 hours before the alert went out and 271 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
- 183 J/kg
- Mixed-layer CIN
- -92 J/kg
- Mixed-layer LCL
- 1023 m above ground
- 0-6 km bulk shear
- 50 kt
- 0-1 km storm-relative helicity
- 92 m²/s²
- 0-3 km storm-relative helicity
- 181 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted.
238 WWUS20 KWNS 070422 SEL1 SPC WW 070422 ILZ000-MOZ000-071200- URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 21 NWS Storm Prediction Center Norman OK 1025 PM CST Fri Mar 6 2026 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of West-Central Illinois East-Central Missouri * Effective this Friday night and Saturday morning from 1025 PM until 600 AM CST. * Primary threats include... Scattered damaging wind gusts to 70 mph likely Scattered large hail events to 1.5 inches in diameter possible A tornado or two possible SUMMARY...Squall line is slowly maturing across central Missouri. Damaging winds may become more common with this line of storms as it surges across east-central Missouri early this morning. A tornado or two can not be ruled out, though damaging winds are the primary concern. The severe thunderstorm watch area is approximately along and 60 statute miles east and west of a line from 55 miles south southwest of Scott Afb IL to 60 miles northwest of Saint Louis MO. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU1). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for 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. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 18...WW 19...WW 20... AVIATION...A few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 24035. ...Darrow
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 6, 8:18 PM CST | Tornado Watch | SPC | Rock Island | 6 hr |
| Mar 7, 2:44 AM CST | Mesoscale Discussion | SPC | Alexander, Bond, Clark, Clay, Clinton, Coles and 30 more | 2 hr |
| Mar 7, 5:40 AM CST | Mesoscale Discussion | SPC | Alexander, Franklin, Gallatin, Hamilton, Hardin, Jackson and 9 more | 2 hr |
| Mar 6, 7:43 PM CST | Mesoscale Discussion | SPC | Barton, Bates, Benton, Cedar, Dade, Henry and 4 more | 92 min |
| Mar 6, 9:43 PM CST | Mesoscale Discussion | SPC | Andrew, Buchanan, Caldwell, Clinton, Daviess, DeKalb and 10 more | 2 hr |
| Mar 6, 10:08 PM CST | Mesoscale Discussion | SPC | Callaway, Camden, Cole, Crawford, Dallas, Dent and 14 more | 67 min |
| Mar 7, 7:53 AM CST | Severe Thunderstorm Watch | SPC | Dunklin, Pemiscot | 8 hr |
Nearby
Severe Thunderstorm Watches in Missouri, 2026Severe Thunderstorm Watches in Illinois, 2026Every severe thunderstorm watch in 2026
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.