Alert archive / Illinois / Mesoscale Discussions in 2003
Mesoscale Discussion 922
The Storm Prediction Center issued this mesoscale discussion at May 10, 2003, 4:48 PM CDT for 31 counties in Illinois; 30 counties in Missouri. It was in force for 87 min.
The area
The outline as issued.
The facts
- Issued
- May 10, 2003, 4:48 PM CDT (21:48 UTC)
- Expired
- May 10, 2003, 6:15 PM CDT
- In force
- 87 min
- Issued by
- the Storm Prediction Center
All 61 counties
Adams County, IL, Bond County, IL, Brown County, IL, Calhoun County, IL, Cass County, IL, Christian County, IL, Clinton County, IL, DeWitt County, IL, Effingham County, IL, Fayette County, IL, Greene County, IL, Hancock County, IL, Jersey County, IL, Logan County, IL, Macon County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Mason County, IL, Menard County, IL, Monroe County, IL, Montgomery County, IL, Morgan County, IL, Moultrie County, IL, Pike County, IL, Saint Clair County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Shelby County, IL, Washington County, IL, Adair County, MO, Audrain County, MO, Benton County, MO, Boone County, MO, Callaway County, MO, Chariton County, MO, City of Saint Louis, MO, Cole County, MO, Cooper County, MO, Franklin County, MO, Gasconade County, MO, Howard County, MO, Jefferson County, MO, Knox County, MO, Lewis County, MO, Lincoln County, MO, Macon County, MO, Marion County, MO, Moniteau County, MO, Monroe County, MO, Montgomery County, MO, Morgan County, MO, Osage 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), 76 km from the middle of the area, began a volume at 21:47 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.
The watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Lincoln, IL (KILX), launched 12:00Z, 9.8 hours before the alert went out and 224 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
- 474 J/kg
- Mixed-layer CIN
- -156 J/kg
- Mixed-layer LCL
- 763 m above ground
- 0-6 km bulk shear
- 50 kt
- 0-1 km storm-relative helicity
- 106 m²/s²
- 0-3 km storm-relative helicity
- 168 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.8
The text
As transmitted, in the capitals the NWS used until 2016.
798 ACUS11 KWNS 102148 SWOMCD SPC MCD 102148 ILZ000-MOZ000-IAZ000-102315- MESOSCALE DISCUSSION 0922 NWS STORM PREDICTION CENTER NORMAN OK 0448 PM CDT SAT MAY 10 2003 AREAS AFFECTED...CNTRL/ERN MO THROUGH CNTRL AND S CNTRL IL CONCERNING...TORNADO WATCH 337... VALID 102148Z - 102315Z POTENTIAL FOR STRONG TORNADOES AND VERY LARGE HAIL REMAINS HIGH ACROSS N CNTRL/NE MO AT THIS TIME. SEVERAL SUPERCELLS CAPABLE OF PRODUCING DAMAGING LONG LIVED TORNADOES EXPECTED TO CONTINUE EWD INTO ERN MO AND EVENTUALLY CROSSING INTO WRN AND CNTRL IL AFTER 23Z. TORNADO WATCH WILL LIKELY BE ISSUED FARTHER EWD INTO IL WITHIN THE HOUR. LATEST SURFACE AND SATELLITE DATA SHOW A SURFACE BOUNDARY LIFTING NWD THROUGH E CNTRL MO. THIS BOUNDARY SEPARATES VERY UNSTABLE AIR TO ITS SOUTH FROM AIR THAT IS LESS UNSTABLE ACROSS IL DUE TO PREVIOUS CONVECTION. HOWEVER...THE ATMOSPHERE WILL DESTABILIZE NWWD WITH TIME INTO IL...LEAVING A LARGER UNSTABLE WARM SECTOR FOR UPSTREAM SUPERCELLS TO TRAVEL THROUGH. LOW LEVEL AND DEEP LAYER SHEAR PROFILES ARE ALSO EXPECTED TO CONTINUE TO INCREASE WITH TIME AS THE LOW LEVEL FLOW STRENGTHENS AND BACKS IN RESPONSE TO CYCLOGENESIS OVER MO. ..DIAL.. 05/10/2003 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PAH...ILX...LSX...DVN...SGF...EAX... 40349276 40459069 40328902 39478828 38338892 38249073 38259242 38309338
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 9, 7:47 PM CDT | Mesoscale Discussion | SPC | Calhoun, Greene, Morgan, Pike, Scott | 88 min |
| May 9, 8:40 PM CDT | Mesoscale Discussion | SPC | Bond, Champaign, Christian, Clark, Clinton, Coles and 18 more | 2 hr |
| May 9, 10:04 PM CDT | Mesoscale Discussion | SPC | Adams | 26 min |
| May 9, 10:40 PM CDT | Severe Thunderstorm Watch | SPC | Brown, Cass, Champaign, DeWitt, Ford, Fulton and 22 more | 5 hr |
| May 10, 5:43 AM CDT | Mesoscale Discussion | SPC | Adams, Brown, Calhoun, Cass, Christian, Fulton and 15 more | 92 min |
| May 10, 5:50 AM CDT | Severe Thunderstorm Watch | SPC | Adams, Bond, Brown, Calhoun, Cass, Christian and 25 more | 5 hr |
| May 10, 8:30 AM CDT | Tornado Watch | SPC | Champaign, Clark, Clay, Coles, Crawford, Cumberland and 9 more | 6 hr |
| May 10, 9:25 AM CDT | Mesoscale Discussion | SPC | Edwards, Franklin, Gallatin, Hamilton, Hardin, Jackson and 14 more | 2 hr |
| May 10, 10:39 AM CDT | Mesoscale Discussion | SPC | Clark, Clay, Coles, Crawford, Cumberland, Douglas and 5 more | 2 hr |
| May 10, 10:54 AM CDT | Mesoscale Discussion | SPC | Adams, Alexander, Bond, Brown, Calhoun, Cass and 69 more | 66 min |
| May 10, 12:38 PM CDT | Mesoscale Discussion | SPC | Clay, Crawford, Jasper, Lawrence, Richland | 97 min |
| May 10, 3:17 PM CDT | Mesoscale Discussion | SPC | Hancock, Henderson, Mercer, Rock Island | 58 min |
| May 10, 3:50 PM CDT | Tornado Watch | SPC | Bureau, Carroll, Fulton, Henderson, Henry, Jo Daviess and 14 more | 6 hr |
| May 10, 4:00 PM CDT | Tornado Watch | SPC | Franklin, Jackson, Perry, Randolph, Union | 5 hr |
| May 10, 5:40 PM CDT | Tornado Watch | SPC | Adams, Bond, Brown, Calhoun, Cass, Christian and 21 more | 5 hr |
| May 10, 6:41 PM CDT | Mesoscale Discussion | SPC | Adams, Bond, Brown, Calhoun, Cass, Christian and 14 more | 64 min |
| May 9, 11:00 PM CDT | Severe Thunderstorm Watch | SPC | Adair, Barton, Bates, Benton, Caldwell, Carroll and 36 more | 6 hr |
| May 10, 1:15 AM CDT | Severe Thunderstorm Watch | SPC | Andrew | 5 hr |
| May 10, 1:22 AM CDT | Mesoscale Discussion | SPC | Newton | 83 min |
| May 10, 2:28 AM CDT | Mesoscale Discussion | SPC | Andrew, Buchanan | 92 min |
| May 10, 3:05 AM CDT | Tornado Watch | SPC | Barton, Bates, Benton, Cedar, Dade, Henry and 7 more | 5 hr |
| May 10, 3:15 AM CDT | Severe Thunderstorm Watch | SPC | Adair, Andrew, Atchison, Buchanan, Caldwell, Carroll and 25 more | 5 hr |
| May 10, 5:27 AM CDT | Mesoscale Discussion | SPC | Barton, Bates, Benton, Cass, Cedar, Dade and 9 more | 93 min |
| May 10, 7:06 AM CDT | Mesoscale Discussion | SPC | Adair, Andrew, Atchison, Buchanan, Caldwell, Carroll and 25 more | 54 min |
| May 10, 10:58 AM CDT | Mesoscale Discussion | SPC | Adair, Andrew, Audrain, Barton, Bates, Benton and 42 more | 2 hr |
| May 10, 11:35 AM CDT | Tornado Watch | SPC | Adair, Audrain, Bates, Benton, Boone, Caldwell and 38 more | 7 hr |
| May 10, 11:55 AM CDT | Tornado Watch | SPC | Barry, Barton, Camden, Cedar, Christian, Dade and 13 more | 7 hr |
| May 10, 1:42 PM CDT | Mesoscale Discussion | SPC | Adair, Audrain, Bates, Benton, Boone, Caldwell and 38 more | 2 hr |
| May 10, 1:59 PM CDT | Mesoscale Discussion | SPC | Barry, Barton, Camden, Cedar, Christian, Dade and 12 more | 2 hr |
| May 10, 3:30 PM CDT | Mesoscale Discussion | SPC | Crawford, Dent, Douglas, Franklin, Gasconade, Howell and 16 more | 2 hr |
Nearby
Mesoscale Discussions in Illinois, 2003Mesoscale Discussions in Missouri, 2003Every mesoscale discussion in 2003
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.