Alert archive / Missouri / Mesoscale Discussions in 2005
Mesoscale Discussion 640
The Storm Prediction Center issued this mesoscale discussion at Apr 21, 2005, 8:03 PM CDT for 16 counties in Illinois; 18 counties in Missouri. It was in force for 87 min.
The area
The outline as issued.
The facts
- Issued
- Apr 21, 2005, 8:03 PM CDT (01:03 UTC)
- Expired
- Apr 21, 2005, 9:30 PM CDT
- In force
- 87 min
- Issued by
- the Storm Prediction Center
All 34 counties
Bond County, IL, Calhoun County, IL, Clinton County, IL, Franklin County, IL, Hamilton County, IL, Jefferson County, IL, Jersey County, IL, Madison County, IL, Marion County, IL, Monroe County, IL, Perry County, IL, Pike County, IL, Randolph County, IL, Saint Clair County, IL, Washington County, IL, White County, IL, Audrain County, MO, Boone County, MO, Callaway County, MO, City of Saint Louis, MO, Franklin County, MO, Gasconade County, MO, Howard County, MO, Jefferson County, MO, Lincoln County, MO, Monroe County, MO, Montgomery County, MO, Osage County, MO, Pike County, MO, Ralls County, MO, Randolph County, MO, Saint Charles County, MO, Saint Louis County, MO, Warren County, MO
The radar
The St Louis radar (KLSX), 8 km from the middle of the area, began a volume at 01:02 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 00:00Z, 1.1 hours before the alert went out and 239 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
- 513 m above ground
- 0-6 km bulk shear
- 37 kt
- 0-1 km storm-relative helicity
- 70 m²/s²
- 0-3 km storm-relative helicity
- 205 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 21, 8:19 PM CDT | Mesoscale Discussion | SPC | Alexander, Johnson, Massac, Pope, Pulaski, Saline and 1 more | 86 min |
| Apr 21, 10:25 PM CDT | Mesoscale Discussion | SPC | Calhoun, Jersey, Madison, Monroe, Randolph, Saint Clair | 65 min |
| Apr 21, 11:50 PM CDT | Severe Thunderstorm Watch | SPC | Clinton, Edwards, Franklin, Hamilton, Jackson, Jefferson and 9 more | 6 hr |
| Apr 22, 3:09 AM CDT | Mesoscale Discussion | SPC | Alexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 13 more | 66 min |
| Apr 22, 10:56 AM CDT | Mesoscale Discussion | SPC | Christian, Clark, Clay, Coles, Crawford, Cumberland and 15 more | 94 min |
| Apr 22, 1:30 PM CDT | Severe Thunderstorm Watch | SPC | Champaign, Clark, Clay, Coles, Crawford, Cumberland and 19 more | 8 hr |
| Apr 21, 7:47 PM CDT | Mesoscale Discussion | SPC | Barry, Barton, Camden, Cedar, Christian, Dade and 22 more | 88 min |
| Apr 21, 9:50 PM CDT | Mesoscale Discussion | SPC | Caldwell, Carroll, Cass, Clay, Clinton, Daviess and 8 more | 55 min |
Nearby
Mesoscale Discussions in Missouri, 2005Mesoscale Discussions in Illinois, 2005Every mesoscale discussion in 2005
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.