Alert archive / Illinois / Mesoscale Discussions in 2020
Mesoscale Discussion 170
The Storm Prediction Center issued this mesoscale discussion at Mar 12, 2020, 1:28 PM CDT for 4 states. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Mar 12, 2020, 1:28 PM CDT (18:28 UTC)
- Expired
- Mar 12, 2020, 3:30 PM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
All 30 counties
Alexander County, IL, Franklin County, IL, Gallatin County, IL, Hamilton County, IL, Hardin County, IL, Jackson County, IL, Jefferson County, IL, Johnson County, IL, Massac County, IL, Perry County, IL, Pope County, IL, Pulaski County, IL, Randolph County, IL, Saline County, IL, Union County, IL, Washington County, IL, White County, IL, Williamson County, IL, Posey County, IN, Ballard County, KY, Crittenden County, KY, Livingston County, KY, Lyon County, KY, McCracken County, KY, Union County, KY, Webster County, KY, Bollinger County, MO, Cape Girardeau County, MO, Perry County, MO, Sainte Genevieve County, MO
The radar
The Paducah radar (KPAH), 72 km from the middle of the area, began a volume at 18:31 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
Nashville Metro, TN (KBNA), launched 12:00Z, 6.5 hours before the alert went out and 280 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
- 662 m above ground
- 0-6 km bulk shear
- 44 kt
- 0-1 km storm-relative helicity
- 156 m²/s²
- 0-3 km storm-relative helicity
- 182 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 12, 9:21 AM CDT | Mesoscale Discussion | SPC | Madison, Monroe, Saint Clair | 114 min |
| Mar 12, 11:13 AM CDT | Mesoscale Discussion | SPC | Alexander, Gallatin, Hardin, Johnson, Massac, Pope and 4 more | 2 hr |
| Mar 12, 11:44 AM CDT | Tornado Watch | SPC | Alexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 13 more | 6 hr |
| Mar 12, 2:31 PM CDT | Mesoscale Discussion | SPC | Alexander, Pulaski | 89 min |
| Mar 12, 3:20 PM CDT | Mesoscale Discussion | SPC | Hardin, Pope | 85 min |
| Mar 12, 3:44 PM CDT | Tornado Watch | SPC | Alexander, Jackson, Johnson, Massac, Pulaski, Union | 7 hr |
| Mar 12, 5:09 PM CDT | Tornado Watch | SPC | Adair, Allen, Barren, Boyle, Breckinridge, Bullitt and 30 more | 5 hr |
| Mar 12, 6:20 PM CDT | Mesoscale Discussion | SPC | Adair, Barren, Clinton, Cumberland, Edmonson, Green and 6 more | 85 min |
| Mar 12, 5:51 PM CDT | Mesoscale Discussion | SPC | Butler, Dunklin, New Madrid, Pemiscot, Ripley | 84 min |
Nearby
Mesoscale Discussions in Illinois, 2020Mesoscale Discussions in Kentucky, 2020Mesoscale Discussions in Missouri, 2020Every mesoscale discussion in 2020
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.