Alert archive / Missouri / Mesoscale Discussions in 2011
Mesoscale Discussion 935
The Storm Prediction Center issued this mesoscale discussion at May 24, 2011, 4:55 PM CDT for 11 counties in Illinois; 22 counties in Missouri. It was in force for 65 min.
The area
The outline as issued.
The facts
- Issued
- May 24, 2011, 4:55 PM CDT (21:55 UTC)
- Expired
- May 24, 2011, 6:00 PM CDT
- In force
- 65 min
- Issued by
- the Storm Prediction Center
All 33 counties
Adams County, IL, Brown County, IL, Calhoun County, IL, Greene County, IL, Jersey County, IL, Macoupin County, IL, Madison County, IL, Monroe County, IL, Pike County, IL, Saint Clair County, IL, Scott County, IL, Audrain County, MO, Boone County, MO, Callaway County, MO, City of Saint Louis, MO, Cole County, MO, Franklin County, MO, Gasconade County, MO, Jefferson County, MO, Knox County, MO, Lewis County, MO, Lincoln County, MO, Marion County, MO, Moniteau County, MO, Monroe County, MO, Montgomery County, MO, Osage County, MO, Pike County, MO, Ralls County, MO, Saint Charles County, MO, Saint Louis County, MO, Shelby County, MO, Warren County, MO
The radar
The St Louis radar (KLSX), 66 km from the middle of the area, began a volume at 21:58 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 12:00Z, 9.9 hours before the alert went out and 254 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
- 518 J/kg
- Mixed-layer CIN
- -69 J/kg
- Mixed-layer LCL
- 941 m above ground
- 0-6 km bulk shear
- 19 kt
- 0-1 km storm-relative helicity
- -14 m²/s²
- 0-3 km storm-relative helicity
- 47 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.2
The text
As transmitted, in the capitals the NWS used until 2016.
107
ACUS11 KWNS 242155
SWOMCD
SPC MCD 242155
ILZ000-MOZ000-242300-
MESOSCALE DISCUSSION 0935
NWS STORM PREDICTION CENTER NORMAN OK
0455 PM CDT TUE MAY 24 2011
AREAS AFFECTED...NERN/E-CNTRL MO...W-CNTRL IL
CONCERNING...SEVERE THUNDERSTORM WATCH 359...
VALID 242155Z - 242300Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 359
CONTINUES.
REGIONAL RADAR IMAGERY INDICATES FORWARD PROPAGATING QLCS HAS
UNDERGONE SIGNIFICANT WEAKENING DURING THE LAST HR AS IT ENCOUNTERS
A MORE STABLE ENVIRONMENT. MEANWHILE OVER FAR S-SWRN PORTIONS OF THE
WATCH...SWD TRAILING OUTFLOW BOUNDARY IS INTERCEPTING NWD RETURN OF
RICH LOW-LEVEL MOISTURE /SURFACE DEWPOINTS IN THE MID TO UPR 60S/.
RUC SOUNDINGS INDICATE AIRMASS WILL BE MODERATELY UNSTABLE AND
UNCAPPED OVER THIS AREA...WHICH COULD FAVOR INITIATION OF NEW STORMS
DURING THE NEXT FEW HRS. IF NEW ACTIVITY OCCURS...SHEAR PROFILES
WOULD BE FAVORABLE FOR SUPERCELLS. OTHERWISE...AS QLCS CONTINUES TO
DECAY DURING THE NEXT HR OR TWO OVER NERN/E-CNTRL MO AND W-CNTRL
IL...THREAT FOR DAMAGING WINDS/LARGE HAIL SHOULD BEGIN TO WANE.
..GARNER.. 05/24/2011
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...ILX...LSX...SGF...EAX...
LAT...LON 40239233 40139036 39519034 39518968 38218971 38009062
38199079 38329237 38559279 39269231 40239233SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 24, 1:11 PM CDT | Mesoscale Discussion | SPC | Bureau, Ford, Grundy, Henry, Iroquois, Kankakee and 12 more | 94 min |
| May 24, 1:38 PM CDT | Severe Thunderstorm Watch | SPC | Adams, Brown, Calhoun, Greene, Jersey, Macoupin and 4 more | 5 hr |
| May 24, 9:18 AM CDT | Mesoscale Discussion | SPC | Bates, Cass, Jackson, Vernon | 87 min |
| May 24, 1:35 PM CDT | Mesoscale Discussion | SPC | Audrain, Boone, Caldwell, Callaway, Carroll, Chariton and 24 more | 25 min |
Nearby
Mesoscale Discussions in Missouri, 2011Mesoscale Discussions in Illinois, 2011Every mesoscale discussion in 2011
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.