Alert archive / Missouri / Severe Thunderstorm Watches in 2001
Severe Thunderstorm Watch 749
The Storm Prediction Center issued this severe thunderstorm watch at Sep 20, 2001, 6:45 PM CDT for 24 counties in Illinois; 27 counties in Missouri. It was in force for 4 hr.
The area
The outline as issued.
The facts
- Issued
- Sep 20, 2001, 6:45 PM CDT (23:45 UTC)
- Expired
- Sep 20, 2001, 11:00 PM CDT
- In force
- 4 hr
- Issued by
- the Storm Prediction Center
All 51 counties
Adams County, IL, Brown County, IL, Calhoun County, IL, Cass County, IL, Christian County, IL, DeWitt County, IL, Fulton County, IL, Greene County, IL, Hancock County, IL, Jersey County, IL, Logan County, IL, Macon County, IL, Macoupin County, IL, Mason County, IL, McDonough County, IL, McLean County, IL, Menard County, IL, Morgan County, IL, Piatt County, IL, Pike County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Tazewell County, IL, Audrain County, MO, Benton County, MO, Boone County, MO, Callaway County, MO, Cole County, MO, Cooper County, MO, Franklin County, MO, Gasconade County, MO, Henry County, MO, Howard County, MO, Lincoln County, MO, Maries County, MO, Marion County, MO, Miller County, MO, Moniteau County, MO, Monroe County, MO, Montgomery County, MO, Morgan County, MO, Osage County, MO, Pettis County, MO, Pike County, MO, Ralls County, MO, Randolph County, MO, Saint Charles County, MO, Saint Louis County, MO, Shelby County, MO, Warren County, MO
The radar
The St Louis radar (KLSX), 98 km from the middle of the area, began a volume at 23:48 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.
Warnings issued inside it
7 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 20, 6:47 PM CDT | Severe Thunderstorm Warning | EAX | Cooper, Howard | 58 min |
| Sep 20, 7:04 PM CDT | Severe Thunderstorm Warning | EAX | Pettis | 41 min |
| Sep 20, 7:27 PM CDT | Severe Thunderstorm Warning | SGF | Morgan | 63 min |
| Sep 20, 7:41 PM CDT | Severe Thunderstorm Warning | LSX | Adams | 34 min |
| Sep 20, 8:26 PM CDT | Severe Thunderstorm Warning | SGF | Miller, Morgan | 64 min |
| Sep 20, 9:12 PM CDT | Severe Thunderstorm Warning | LSX | Marion | 33 min |
| Sep 20, 9:27 PM CDT | Severe Thunderstorm Warning | SGF | Camden, Miller, Morgan | 63 min |
The nearest sounding before it
Lincoln, IL (KILX), launched 12:00Z, 11.8 hours before the alert went out and 288 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
- 31 J/kg
- Mixed-layer CIN
- -44 J/kg
- Mixed-layer LCL
- 799 m above ground
- 0-6 km bulk shear
- 33 kt
- 0-1 km storm-relative helicity
- 75 m²/s²
- 0-3 km storm-relative helicity
- 103 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 WWUS9 KMKC 202342 SEL9 MKC WW 202337 ILZ000-MOZ000-210400- URGENT - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WATCH NUMBER 749 STORM PREDICTION CENTER NORMAN OK 637 PM CDT THU SEP 20 2001 THE STORM PREDICTION CENTER HAS ISSUED A SEVERE THUNDERSTORM WATCH FOR PORTIONS OF WESTERN AND CENTRAL ILLINOIS CENTRAL AND EASTERN MISSOURI EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 645 PM UNTIL 1100 PM CDT. HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS. THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 90 STATUTE MILES EAST AND WEST OF A LINE FROM 45 MILES SOUTHWEST OF JEFFERSON CITY MISSOURI TO 20 MILES WEST NORTHWEST OF BLOOMINGTON ILLINOIS. 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 744...WW 745...WW 746...WW 747...WW 748... DISCUSSION...BOW ECHO AND COMMA HEAD VORTICITY MAX APPEARS TO BE DEVELOPING IN SERN IA AND NRN MO. THIS FEATURE SHOULD MOVE ESEWD WITH INCREASING RISK OF WIND DAMAGE. LARGE HAIL IS ALSO POSSIBLE THOUGH WIND DAMAGE SHOULD BE MAIN THREAT. AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT TO 1 INCH EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM MOTION VECTOR 29035. ...JOHNS 403,0873 380,0910 380,0942 403,0905 @ RUKWBC +KDENWWUS9 KMKC 202342 SEL9 MKC WW 202337 ILZ000-MOZ000-210400- URGENT - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WATCH NUMBER 749 STORM PREDICTION CENTER NORMAN OK 637 PM CDT THU SEP 20 2001 THE STORM PREDICTION CENTER HAS ISSUED A SEVERE THUNDERSTORM WATCH FOR PORTIONS OF WESTERN AND CENTRAL ILLINOIS CENTRAL AND EASTERN MISSOURI EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 645 PM UNTIL 1100 PM CDT. HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS. THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 90 STATUTE MILES EAST AND WEST OF A LINE FROM 45 MILES SOUTHWEST OF JEFFERSON CITY MISSOURI TO 20 MILES WEST NORTHWEST OF BLOOMINGTON ILLINOIS. 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 744...WW 745...WW 746...WW 747...WW 748... DISCUSSION...BOW ECHO AND COMMA HEAD VORTICITY MAX APPEARS TO BE DEVELOPING IN SERN IA AND NRN MO. THIS FEATURE SHOULD MOVE ESEWD WITH INCREASING RISK OF WIND DAMAGE. LARGE HAIL IS ALSO POSSIBLE THOUGH WIND DAMAGE SHOULD BE MAIN THREAT. AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT TO 1 INCH EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM MOTION VECTOR 29035. ...JOHNS 403,0873 380,0910 380,0942 403,0905
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 20, 5:15 PM CDT | Severe Thunderstorm Watch | SPC | Carroll, Henderson, Jo Daviess, Mercer, Rock Island, Stephenson and 1 more | 6 hr |
| Sep 20, 5:45 PM CDT | Severe Thunderstorm Watch | SPC | Hancock | 5 hr |
| Sep 20, 3:00 PM CDT | Severe Thunderstorm Watch | SPC | Atchison, Holt, Nodaway, Worth | 5 hr |
Nearby
Severe Thunderstorm Watches in Missouri, 2001Severe Thunderstorm Watches in Illinois, 2001Every severe thunderstorm watch in 2001
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.