Alert archive / Missouri / Mesoscale Discussions in 2011
Mesoscale Discussion 467
The Storm Prediction Center issued this mesoscale discussion at Apr 19, 2011, 2:53 AM CDT for 27 counties in Illinois; 46 counties in Missouri. It was in force for 67 min.
The area
The outline as issued.
The facts
- Issued
- Apr 19, 2011, 2:53 AM CDT (07:53 UTC)
- Expired
- Apr 19, 2011, 4:00 AM CDT
- In force
- 67 min
- Issued by
- the Storm Prediction Center
All 73 counties
Adams County, IL, Bond County, IL, Brown County, IL, Calhoun County, IL, Cass County, IL, Christian County, IL, Clay County, IL, Clinton County, IL, Effingham County, IL, Fayette County, IL, Greene County, IL, Jersey County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Menard County, IL, Monroe County, IL, Montgomery County, IL, Morgan County, IL, Pike County, IL, Saint Clair County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Shelby County, IL, Washington County, IL, Wayne County, IL, Adair County, MO, Audrain County, MO, Boone County, MO, Caldwell County, MO, Callaway County, MO, Carroll County, MO, Chariton County, MO, City of Saint Louis, MO, Clark County, MO, Cole County, MO, Cooper County, MO, Crawford County, MO, Daviess County, MO, Franklin County, MO, Gasconade County, MO, Grundy County, MO, Howard County, MO, Jefferson County, MO, Knox County, MO, Lewis County, MO, Lincoln County, MO, Linn County, MO, Livingston County, MO, Macon County, MO, Maries County, MO, Marion County, MO, Miller County, MO, Moniteau County, MO, Monroe County, MO, Montgomery County, MO, Morgan County, MO, Osage County, MO, Pettis County, MO, Pike County, MO, Putnam County, MO, Ralls County, MO, Randolph County, MO, Ray County, MO, Saint Charles County, MO, Saint Louis County, MO, Saline County, MO, Schuyler County, MO, Scotland County, MO, Shelby County, MO, Sullivan County, MO, Warren County, MO
The radar
The St Louis radar (KLSX), 119 km from the middle of the area, began a volume at 07:55 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
Davenport, (KDVN), launched 00:00Z, 7.9 hours before the alert went out and 277 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
- 641 m above ground
- 0-6 km bulk shear
- 63 kt
- 0-1 km storm-relative helicity
- -36 m²/s²
- 0-3 km storm-relative helicity
- 152 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
476
ACUS11 KWNS 190753
SWOMCD
SPC MCD 190753
ILZ000-MOZ000-IAZ000-190900-
MESOSCALE DISCUSSION 0467
NWS STORM PREDICTION CENTER NORMAN OK
0253 AM CDT TUE APR 19 2011
AREAS AFFECTED...PARTS OF NRN AND CNTRL MO INTO PARTS OF SRN IL
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY
VALID 190753Z - 190900Z
A WW LIKELY WILL BE NEEDED WITHIN THE NEXT HOUR OR SO.
AN INCREASE IN THUNDERSTORM DEVELOPMENT IS UNDERWAY ACROSS PARTS OF
THE LOWER MISSOURI VALLEY. THIS ACTIVITY IS BASED WITHIN A
STRENGTHENING LOWER/MID TROPOSPHERIC WARM ADVECTION REGIME...IN
ADVANCE OF A DEEP SURFACE CYCLONE EXPECTED TO CONTINUE MIGRATING
FROM NORTHWEST OKLAHOMA INTO SOUTHEAST KANSAS BY DAYBREAK. CAPPING
ASSOCIATED WITH WARM ELEVATED MIXED LAYER /ROUGHLY DELINEATED BY
+8-10C AT 700 MB/ IS EXPECTED TO PROVIDE THE SOUTHERN/WESTERN LIMIT
OF STORM DEVELOPMENT THROUGH 12-13Z...WITH CONVECTIVE COVERAGE
PRIMARILY INCREASING NORTHEAST OF THE MISSOURI OZARKS...AND EAST OF
KANSAS CITY/ST. JOSEPH ACROSS MUCH OF NORTHERN MISSOURI. A FAIRLY
DEEP AND COLD SURFACE BASED LAYER MAY LIMIT SEVERE POTENTIAL TO THE
RISK OF HAIL ACROSS MUCH OF THE REGION...BUT MOST UNSTABLE CAPE IN
EXCESS OF 1000 J/KG...IN THE PRESENCE OF STRONG CLOUD BEARING LAYER
SHEAR...COULD YIELD FAIRLY LARGE HAIL SIZES. CLOSER TO THE SURFACE
FRONT...ALONG AND NORTH OF THE INTERSTATE 44 CORRIDOR INTO PARTS OF
SOUTHWESTERN ILLINOIS ...THE RISK FOR DAMAGING WIND GUSTS MAY NOT BE
COMPLETELY NEGLIGIBLE.
..KERR.. 04/19/2011
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...PAH...ILX...LSX...DVN...SGF...DMX...EAX...
LAT...LON 40149452 40729240 40249081 39858895 38498804 38139039
37959123 38159293 39489419 40149452SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 18, 11:41 PM CDT | Mesoscale Discussion | SPC | Calhoun, Jersey | 94 min |
| Apr 19, 3:11 AM CDT | Severe Thunderstorm Watch | SPC | Adams, Bond, Brown, Calhoun, Cass, Christian and 30 more | 7 hr |
| Apr 19, 5:52 AM CDT | Mesoscale Discussion | SPC | Adams, Bond, Brown, Calhoun, Cass, Christian and 34 more | 83 min |
| Apr 19, 8:29 AM CDT | Mesoscale Discussion | SPC | Christian, Clark, Coles, Crawford, Cumberland, Douglas and 8 more | 61 min |
| Apr 19, 12:40 PM CDT | Mesoscale Discussion | SPC | Jersey, Madison, Monroe, Saint Clair | 95 min |
| Apr 19, 1:00 PM CDT | Tornado Watch | SPC | Bond, Calhoun, Cass, Champaign, Christian, Clark and 36 more | 10 hr |
| Apr 19, 5:47 PM CDT | Mesoscale Discussion | SPC | Bond, Calhoun, Christian, Clark, Clay, Clinton and 25 more | 88 min |
| Apr 19, 6:24 PM CDT | Mesoscale Discussion | SPC | Alexander, Franklin, Jackson, Johnson, Pulaski, Saline and 2 more | 66 min |
| Apr 19, 6:46 PM CDT | Tornado Watch | SPC | Alexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 13 more | 9 hr |
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.