Alert archive / Illinois / Mesoscale Discussions in 2021
Mesoscale Discussion 1105
The Storm Prediction Center issued this mesoscale discussion at Jun 25, 2021, 10:31 PM CDT for 36 counties in Illinois; 25 counties in Indiana; 8 counties in Missouri. It was in force for 59 min.
The area
The outline as issued.
The facts
- Issued
- Jun 25, 2021, 10:31 PM CDT (03:31 UTC)
- Expired
- Jun 25, 2021, 11:30 PM CDT
- In force
- 59 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 318...319
All 69 counties
Bond County, IL, Calhoun County, IL, Cass County, IL, Champaign County, IL, Christian County, IL, Coles County, IL, DeWitt County, IL, Douglas County, IL, Edgar County, IL, Ford County, IL, Fulton County, IL, Greene County, IL, Iroquois County, IL, Jersey County, IL, Kankakee County, IL, Livingston County, IL, Logan County, IL, Macon County, IL, Macoupin County, IL, Madison County, IL, Mason County, IL, McLean County, IL, Menard County, IL, Montgomery County, IL, Morgan County, IL, Moultrie County, IL, Peoria County, IL, Piatt County, IL, Pike County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Shelby County, IL, Tazewell County, IL, Vermilion County, IL, Woodford County, IL, Benton County, IN, Carroll County, IN, Cass County, IN, Clinton County, IN, Elkhart County, IN, Fountain County, IN, Fulton County, IN, Howard County, IN, Jasper County, IN, Kosciusko County, IN, LaPorte County, IN, Marshall County, IN, Miami County, IN, Montgomery County, IN, Newton County, IN, Parke County, IN, Porter County, IN, Pulaski County, IN, Saint Joseph County, IN, Starke County, IN, Tippecanoe County, IN, Vermillion County, IN, Wabash County, IN, Warren County, IN, White County, IN, City of Saint Louis, MO, Crawford County, MO, Franklin County, MO, Gasconade County, MO, Lincoln County, MO, Saint Charles County, MO, Saint Louis County, MO, Warren County, MO
The radar
The Lincoln radar (KILX), 70 km from the middle of the area, began a volume at 03:35 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 nearest sounding before it
Lincoln, IL (KILX), launched 00:00Z, 3.5 hours before the alert went out and 57 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
- 1254 J/kg
- Mixed-layer CIN
- -26 J/kg
- Mixed-layer LCL
- 910 m above ground
- 0-6 km bulk shear
- 30 kt
- 0-1 km storm-relative helicity
- 105 m²/s²
- 0-3 km storm-relative helicity
- 204 m²/s²
- Significant tornado parameter
- 0.7
- Supercell composite
- 6.6
The text
As transmitted.
050
ACUS11 KWNS 260331
SWOMCD
SPC MCD 260331
INZ000-MIZ000-ILZ000-MOZ000-260430-
Mesoscale Discussion 1105
NWS Storm Prediction Center Norman OK
1031 PM CDT Fri Jun 25 2021
Areas affected...east-central Missouri northeast to northern Indiana
Concerning...Severe Thunderstorm Watch 318...319...
Valid 260331Z - 260430Z
The severe weather threat for Severe Thunderstorm Watch 318, 319
continues.
SUMMARY...Severe threat continues to diminish across the watch
areas. A brief window of strong wind potential may remain across
eastern Illinois, but the overall convective trends suggest a new
watch likely will not be needed.
DISCUSSION...Overall thunderstorm severity continues to wane across
the watch areas as evidenced by weakening of MESH cores and warming
cloud tops. Additionally, given the loss of diurnal heating, low
level stability should slowly increase overnight, reducing the
potential for organized, severe thunderstorm outflows and brief
tornadoes. However, a recent measured wind gust of 59 knots at
Decatur, IL, reiterates that the wind potential, albeit low, does
remain. Current thinking is that the overall isolated nature of the
threat should preclude the need for a new watch, although a local
extension in time of Severe Thunderstorm Watch 318 may be needed if
the wind potential does not diminish as quickly as expected.
..Marsh.. 06/26/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...IWX...IND...LOT...ILX...LSX...DVN...SGF...
LAT...LON 38359166 40709030 41788609 41628560 40668561 39708705
39228862 38499034 37759124 38359166SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 25, 7:05 PM CDT | Mesoscale Discussion | SPC | Iroquois, Kankakee, Vermilion | 55 min |
| Jun 25, 8:34 PM CDT | Mesoscale Discussion | SPC | Adams, Brown, Calhoun, Cass, Champaign, Christian and 30 more | 86 min |
| Jun 26, 11:45 AM CDT | Mesoscale Discussion | SPC | Calhoun, Cass, Champaign, Christian, DeWitt, Ford and 21 more | 2 hr |
| Jun 26, 12:05 PM CDT | Tornado Watch | SPC | Cass, Champaign, Christian, Coles, Cook, Cumberland and 24 more | 9 hr |
| Jun 26, 2:47 PM CDT | Mesoscale Discussion | SPC | Calhoun, DeWitt, Ford, Greene, Iroquois, Jersey and 8 more | 118 min |
| Jun 26, 6:08 PM CDT | Mesoscale Discussion | SPC | Champaign, Coles, Cumberland, Douglas, Edgar, Ford and 5 more | 67 min |
| Jun 26, 12:48 PM CDT | Mesoscale Discussion | SPC | LaPorte, Saint Joseph | 57 min |
| Jun 26, 6:47 PM CDT | Severe Thunderstorm Watch | SPC | Carroll, Clinton, Fountain, Montgomery, Parke, Tippecanoe and 2 more | 3 hr |
Nearby
Mesoscale Discussions in Illinois, 2021Mesoscale Discussions in Indiana, 2021Mesoscale Discussions in Missouri, 2021Every mesoscale discussion in 2021
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.