Alert archive / Missouri / Mesoscale Discussions in 2012
Mesoscale Discussion 685
The Storm Prediction Center issued this mesoscale discussion at May 3, 2012, 6:42 PM CDT for 23 counties in Illinois; 11 counties in Iowa; 34 counties in Missouri. It was in force for 63 min.
The area
The outline as issued.
The facts
- Issued
- May 3, 2012, 6:42 PM CDT (23:42 UTC)
- Expired
- May 3, 2012, 7:45 PM CDT
- In force
- 63 min
- Issued by
- the Storm Prediction Center
All 68 counties
Appanoose County, IA, Davis County, IA, Decatur County, IA, Des Moines County, IA, Henry County, IA, Lee County, IA, Page County, IA, Ringgold County, IA, Taylor County, IA, Van Buren County, IA, Wayne County, IA, Adams County, IL, Brown County, IL, Cass County, IL, DeWitt County, IL, Fulton County, IL, Greene County, IL, Hancock County, IL, Henderson County, IL, Knox County, IL, Logan County, IL, Mason County, IL, McDonough County, IL, McLean County, IL, Menard County, IL, Morgan County, IL, Peoria County, IL, Pike County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Tazewell County, IL, Warren County, IL, Woodford County, IL, Adair County, MO, Andrew County, MO, Atchison County, MO, Buchanan County, MO, Caldwell County, MO, Carroll County, MO, Chariton County, MO, Clark County, MO, Clinton County, MO, Daviess County, MO, DeKalb County, MO, Gentry County, MO, Grundy County, MO, Harrison County, MO, Holt County, MO, Knox County, MO, Lewis County, MO, Linn County, MO, Livingston County, MO, Macon County, MO, Marion County, MO, Mercer County, MO, Monroe County, MO, Nodaway County, MO, Pike County, MO, Putnam County, MO, Ralls County, MO, Randolph County, MO, Ray County, MO, Schuyler County, MO, Scotland County, MO, Shelby County, MO, Sullivan County, MO, Worth County, MO
The radar
The Quad Cities radar (KDVN), 176 km from the middle of the area, began a volume at 23:42 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
Davenport, (KDVN), launched 12:00Z, 11.7 hours before the alert went out and 181 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
- 2051 J/kg
- Mixed-layer CIN
- -31 J/kg
- Mixed-layer LCL
- 770 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 4 m²/s²
- 0-3 km storm-relative helicity
- 85 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 3.7
The text
As transmitted, in the capitals the NWS used until 2016.
510
ACUS11 KWNS 032343
SWOMCD
SPC MCD 032342
ILZ000-MOZ000-IAZ000-KSZ000-NEZ000-040045-
MESOSCALE DISCUSSION 0685
NWS STORM PREDICTION CENTER NORMAN OK
0642 PM CDT THU MAY 03 2012
AREAS AFFECTED...CNTRL IL TO NRN MO AND FAR SRN IA
CONCERNING...TORNADO WATCH 232...
VALID 032342Z - 040045Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 232 CONTINUES.
SUMMARY...NEW WW PROPOSAL WILL BE COORDINATED SOON FOR AREAS W OF WW
232 AS TSTMS LIKELY INCREASE IN COVERAGE WITHIN A DIFFERENTIAL
HEATING ZONE/REMNANT OUTFLOW BOUNDARY.
DISCUSSION...CONVECTION HAS GRADUALLY INCREASED ALONG A REMNANT
OUTFLOW BOUNDARY FROM NEAR PIA W/SWWD TO NRN MO. AIR MASS S OF THIS
BOUNDARY IS STRONGLY UNSTABLE WITH MLCAPE OF 2500 TO 3500 J/KG AND
PARTIAL 00Z TOP/ILX/DVN RAOBS INDICATING MINIMAL MLCIN. TSTMS SHOULD
BLOSSOM WITHIN THIS CORRIDOR BY SUNSET AS THE LLJ INTENSIFIES THIS
EVENING. PRIMARY INITIAL THREATS SHOULD BE LARGE /POTENTIALLY
SIGNIFICANT/ HAIL AND PERHAPS A BRIEF TORNADO. UPSCALE GROWTH INTO
AN MCS APPEARS PLAUSIBLE WITH THE RISK TRANSITIONING TO DAMAGING
WINDS LATER THIS EVENING.
..GRAMS.. 05/03/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LOT...ILX...LSX...DVN...DMX...EAX...OAX...
LAT...LON 41058999 40908894 40398868 39708918 39289029 39189309
39399458 40349565 40709570 40949470 40939273 41019103
41058999SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 3, 1:07 PM CDT | Severe Thunderstorm Watch | SPC | Boone, Cook, DeKalb, DuPage, Kane, Kendall and 5 more | 6 hr |
| May 3, 2:53 PM CDT | Mesoscale Discussion | SPC | Boone, Cook, DeKalb, DuPage, Kane, Lake and 3 more | 67 min |
| May 3, 3:53 PM CDT | Mesoscale Discussion | SPC | Brown, Bureau, Cass, DeWitt, Fulton, Greene and 22 more | 37 min |
| May 3, 4:20 PM CDT | Tornado Watch | SPC | Bureau, Cass, Champaign, DeWitt, Ford, Fulton and 26 more | 8 hr |
| May 3, 6:22 PM CDT | Mesoscale Discussion | SPC | Cook, DeKalb, DuPage, Kane, Kendall, Lake and 1 more | 23 min |
| May 3, 6:41 PM CDT | Severe Thunderstorm Watch | SPC | Boone, Cook, DeKalb, DuPage, Ford, Grundy and 12 more | 5 hr |
| May 2, 10:43 PM CDT | Mesoscale Discussion | SPC | Harrison, Monona, Plymouth, Sioux, Woodbury | 62 min |
| May 3, 12:50 AM CDT | Severe Thunderstorm Watch | SPC | Adams, Cass, Fremont, Mills, Montgomery, Page and 2 more | 4 hr |
| May 3, 3:05 AM CDT | Mesoscale Discussion | SPC | Adair, Adams, Cass, Clarke, Decatur, Montgomery and 4 more | 85 min |
| May 3, 2:12 PM CDT | Mesoscale Discussion | SPC | Buena Vista, Calhoun, Cerro Gordo, Cherokee, Clay, Dickinson and 18 more | 2 hr |
| May 3, 3:41 PM CDT | Mesoscale Discussion | SPC | Adair, Adams, Cass, Clarke, Fremont, Madison and 7 more | 2 hr |
Nearby
Mesoscale Discussions in Missouri, 2012Mesoscale Discussions in Illinois, 2012Mesoscale Discussions in Iowa, 2012Every mesoscale discussion in 2012
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.