Alert archive / Illinois / Mesoscale Discussions in 2011

Mesoscale Discussion 948

May 25, 201151 counties in Illinois; 13 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at May 25, 2011, 4:58 AM CDT for 51 counties in Illinois; 13 counties in Missouri. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued
May 25, 2011, 4:58 AM CDT (09:58 UTC)
Expired
May 25, 2011, 6:30 AM CDT
In force
92 min
Issued by
the Storm Prediction Center
All 64 counties

Bond County, IL, Brown County, IL, Calhoun County, IL, Cass County, IL, Champaign County, IL, Christian County, IL, Clay County, IL, Clinton County, IL, Coles County, IL, Cumberland County, IL, DeWitt County, IL, Douglas County, IL, Edgar County, IL, Effingham County, IL, Fayette County, IL, Ford County, IL, Fulton County, IL, Greene County, IL, Iroquois County, IL, Jasper County, IL, Jefferson County, IL, Jersey County, IL, Livingston County, IL, Logan County, IL, Macon County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Mason County, IL, McDonough County, IL, McLean County, IL, Menard County, IL, Monroe County, IL, Montgomery County, IL, Morgan County, IL, Moultrie County, IL, Perry County, IL, Piatt County, IL, Pike County, IL, Randolph County, IL, Richland County, IL, Saint Clair County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Shelby County, IL, Tazewell County, IL, Vermilion County, IL, Washington County, IL, Wayne County, IL, Woodford County, IL, City of Saint Louis, MO, Crawford County, MO, Dent County, MO, Franklin County, MO, Iron County, MO, Jefferson County, MO, Reynolds County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Shannon County, MO, Washington County, MO

The radar

The St Louis radar (KLSX), 79 km from the middle of the area, began a volume at 09:57 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, 10.0 hours before the alert went out and 166 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.

Skew-T log-pSkew-T log-p diagram, Lincoln, IL at 00:00Z on 2011-05-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 375 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 00:00Z on 2011-05-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 30 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
375 J/kg
Mixed-layer CIN
-47 J/kg
Mixed-layer LCL
1724 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
30 m²/s²
0-3 km storm-relative helicity
44 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

925 
ACUS11 KWNS 250958
SWOMCD
SPC MCD 250958 
INZ000-ILZ000-MOZ000-251130-

MESOSCALE DISCUSSION 0948
NWS STORM PREDICTION CENTER NORMAN OK
0458 AM CDT WED MAY 25 2011

AREAS AFFECTED...SOUTHERN/EASTERN MO TO WESTERN/CENTRAL IL

CONCERNING...TORNADO WATCH 366...

VALID 250958Z - 251130Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 366 CONTINUES.

TORNADO WATCH 366 CONTINUES UNTIL 13Z. DAMAGING WINDS WILL REMAIN
THE PRIMARY CONCERN...WITH ISOLATED TORNADOES/SEVERE HAIL POSSIBLE
AS WELL. AN ADDITIONAL WATCH MAY BE NEEDED EARLY THIS MORNING
ESPECIALLY FOR PORTIONS OF CENTRAL IL.

THE GREATEST SEVERE THREAT THROUGH THE EARLY MORNING IS LIKELY TO BE
FOCUSED IN A SOUTHWEST-NORTHEAST ORIENTED CORRIDOR FROM SOUTHEAST MO
/IN THE ST LOUIS METRO/ INTO SOUTHWEST/CENTRAL IL INCLUDING AREAS
ALONG I-70/I-64. POTENTIALLY AIDED BY A PIVOTING LOBE OF FOCUSED
ASCENT/DPVA...A RELATIVE MAXIMA OF SURFACE PRESSURE FALLS ARE NOTED
WITHIN THE AFOREMENTIONED CORRIDOR AS A RELATIVELY WARM/MOIST
AIRMASS IS IN PLACE WITH SURFACE TEMPERATURES IN THE LOWER/MIDDLE
70S AND MIDDLE/UPPER 60S F SURFACE DEWPOINTS. WITH 50+ KT
SOUTH-SOUTHWESTERLY WINDS NOW NOTED IN THE ST LOUIS WSR-88D VWP
WITHIN THE LOWEST 1-3 KM...SCENARIO WILL REMAIN CONDUCIVE FOR FAST
NORTHEASTWARD MOVING QLCS SEGMENTS/EMBEDDED BOWS WITH A DAMAGING
WIND/ISOLATED TORNADO POTENTIAL.

..GUYER.. 05/25/2011

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...IND...PAH...LOT...ILX...LSX...DVN...SGF...

LAT...LON   36999151 37439198 38759100 40439080 41088872 40828783
            40318750 38488805 36999151

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 25, 12:48 AM CDTMesoscale DiscussionSPCAdams, Alexander, Bond, Brown, Calhoun, Cass and 23 more57 min
May 25, 1:22 AM CDTTornado WatchSPCAdams, Brown, Calhoun, Cass, Fulton, Greene and 16 more7 hr
May 25, 5:46 AM CDTTornado WatchSPCBond, Champaign, Christian, Clark, Clay, Clinton and 35 more7 hr
May 25, 7:31 AM CDTMesoscale DiscussionSPCAlexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 13 more59 min
May 25, 7:48 AM CDTMesoscale DiscussionSPCChampaign, Clark, Clay, Clinton, Coles, Crawford and 18 more87 min
May 25, 8:33 AM CDTMesoscale DiscussionSPCChampaign, DeWitt, Douglas, Edgar, Ford, Iroquois and 3 more87 min
May 25, 10:18 AM CDTMesoscale DiscussionSPCBond, Clark, Clay, Clinton, Crawford, Cumberland and 12 more57 min
May 25, 10:37 AM CDTTornado WatchSPCAdams, Brown, Pike7 hr
May 25, 11:02 AM CDTMesoscale DiscussionSPCAlexander, Franklin, Gallatin, Hamilton, Hardin, Jackson and 13 more28 min
May 25, 11:09 AM CDTTornado Watch PDSSPCAlexander, Bond, Calhoun, Christian, Clark, Clay and 41 more10 hr
May 25, 2:31 PM CDTTornado WatchSPCBureau, Cass, Champaign, DeKalb, DeWitt, Ford and 33 more7 hr
May 25, 2:32 PM CDTMesoscale DiscussionSPCCalhoun, Greene, Jersey, Macoupin, Pike, Scott58 min
May 25, 3:10 PM CDTMesoscale DiscussionSPCAlexander, Franklin, Gallatin, Hardin, Jackson, Johnson and 6 more95 min
May 25, 5:48 PM CDTMesoscale DiscussionSPCBureau, Champaign, DeKalb, DeWitt, Douglas, Ford and 19 more117 min
May 25, 6:25 PM CDTMesoscale DiscussionSPCAlexander, Clay, Clinton, Edwards, Franklin, Gallatin and 20 more2 hr
May 24, 7:07 PM CDTMesoscale DiscussionSPCAndrew, Barton, Bates, Buchanan, Cass, Cedar and 14 more53 min
May 24, 7:26 PM CDTTornado WatchSPCAdair, Barry, Barton, Bates, Benton, Buchanan and 48 more7 hr
May 24, 7:42 PM CDTMesoscale DiscussionSPCMcDonald63 min
May 24, 11:24 PM CDTMesoscale DiscussionSPCBenton, Camden, Christian, Cooper, Dallas, Douglas and 15 more96 min
May 25, 9:54 AM CDTMesoscale DiscussionSPCBenton, Butler, Camden, Carter, Christian, Dallas and 24 more96 min
May 25, 11:52 AM CDTMesoscale DiscussionSPCDunklin, Pemiscot83 min
May 25, 12:28 PM CDTTornado Watch PDSSPCDunklin, Pemiscot8 hr
May 25, 1:28 PM CDTMesoscale DiscussionSPCAdair, Audrain, Boone, Caldwell, Callaway, Camden and 44 more92 min
May 25, 2:56 PM CDTMesoscale DiscussionSPCDunklin, Pemiscot94 min
May 25, 5:56 PM CDTMesoscale DiscussionSPCDunklin, Pemiscot64 min

Nearby

Mesoscale Discussions in Illinois, 2011Mesoscale Discussions in Missouri, 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.