Alert archive / Indiana / Mesoscale Discussions in 2021
Mesoscale Discussion 1710
The Storm Prediction Center issued this mesoscale discussion at Sep 7, 2021, 5:25 PM CDT for Champaign County, Vermilion County, Illinois; 7 counties in Indiana. It was in force for 95 min.
The area
The outline as issued.
The facts
- Issued
- Sep 7, 2021, 5:25 PM CDT (22:25 UTC)
- Expired
- Sep 7, 2021, 7:00 PM CDT
- In force
- 95 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 489...490
Counties Champaign County, IL, Vermilion County, IL, Benton County, IN, Carroll County, IN, Cass County, IN, Miami County, IN, Tippecanoe County, IN, Warren County, IN, White County, IN
The radar
The Indianapolis radar (KIND), 129 km from the middle of the area, began a volume at 22:26 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 12:00Z, 10.4 hours before the alert went out and 104 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1964 m above ground
- 0-6 km bulk shear
- 25 kt
- 0-1 km storm-relative helicity
- 93 m²/s²
- 0-3 km storm-relative helicity
- 115 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
374 ACUS11 KWNS 072226 SWOMCD SPC MCD 072225 INZ000-ILZ000-080000- Mesoscale Discussion 1710 NWS Storm Prediction Center Norman OK 0525 PM CDT Tue Sep 07 2021 Areas affected...East-Central IL...Northwest IN Concerning...Severe Thunderstorm Watch 489...490... Valid 072225Z - 080000Z The severe weather threat for Severe Thunderstorm Watch 489, 490 continues. SUMMARY...Isolated damaging wind gusts remain possible with squall line as it propagates east-southeast. DISCUSSION...Secondary mid-level speed max is digging southeast across IA toward the base of the Great Lakes upper trough, and subsequent height falls will continue to spread across portions of the OH Valley in response to this feature. West-southwest/northeast oriented squall line that developed across IL continues to propagate east-southeast in response to this digging speed max, though stronger winds have subsided with the squall line as it approaches weaker buoyancy across IN. This line of storms is expected to gradually advance beyond the southeast portion of ww489 and southwestern corner of ww490 over the next 1-2 hours. However, unless this convection begins to produce more extensive wind gusts it appears the majority of downburst activity will remain mostly sub-severe. New severe thunderstorm watch is not currently anticipated. ..Darrow.. 09/07/2021 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...IWX...IND...LOT...ILX... LAT...LON 40328865 41038631 40718586 40258685 40128832 40328865
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 7, 12:25 PM CDT | Mesoscale Discussion | SPC | Boone, Bureau, Carroll, Cook, DeKalb, DuPage and 9 more | 65 min |
| Sep 7, 1:12 PM CDT | Severe Thunderstorm Watch | SPC | Boone, Bureau, Champaign, Cook, DeKalb, DeWitt and 34 more | 8 hr |
| Sep 7, 3:14 PM CDT | Mesoscale Discussion | SPC | DuPage, Ford, Grundy, Iroquois, Kankakee, Kendall and 11 more | 91 min |
| Sep 7, 1:48 PM CDT | Mesoscale Discussion | SPC | DeKalb, Elkhart, Fulton, Kosciusko, LaGrange, LaPorte and 6 more | 117 min |
| Sep 7, 2:20 PM CDT | Severe Thunderstorm Watch | SPC | Cass, Elkhart, Fulton, Kosciusko, LaGrange, LaPorte and 7 more | 7 hr |
| Sep 7, 4:37 PM CDT | Mesoscale Discussion | SPC | Elkhart, Fulton, Kosciusko, LaGrange, LaPorte, Marshall and 5 more | 83 min |
Nearby
Mesoscale Discussions in Indiana, 2021Mesoscale Discussions in Illinois, 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.