Alert archive / Missouri / Mesoscale Discussions in 2011

Mesoscale Discussion 764

May 12, 20118 counties in Kansas; 31 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at May 12, 2011, 4:54 PM CDT for 8 counties in Kansas; 31 counties in Missouri. It was in force for 66 min.

The area

The outline as issued.

The facts

Issued
May 12, 2011, 4:54 PM CDT (21:54 UTC)
Expired
May 12, 2011, 6:00 PM CDT
In force
66 min
Issued by
the Storm Prediction Center
All 39 counties

Atchison County, KS, Douglas County, KS, Jefferson County, KS, Johnson County, KS, Leavenworth County, KS, Linn County, KS, Miami County, KS, Wyandotte County, KS, Bates County, MO, Benton County, MO, Boone County, MO, Buchanan County, MO, Caldwell County, MO, Camden County, MO, Carroll County, MO, Cass County, MO, Chariton County, MO, Clay County, MO, Clinton County, MO, Cooper County, MO, Daviess County, MO, DeKalb County, MO, Henry County, MO, Hickory County, MO, Howard County, MO, Jackson County, MO, Johnson County, MO, Lafayette County, MO, Linn County, MO, Livingston County, MO, Moniteau County, MO, Morgan County, MO, Pettis County, MO, Platte County, MO, Randolph County, MO, Ray County, MO, Saline County, MO, St. Clair County, MO, Vernon County, MO

The radar

The Pleasant Hill radar (KEAX), 56 km from the middle of the area, began a volume at 21:54 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

Topeka, KS (KTOP), launched 12:00Z, 9.9 hours before the alert went out and 174 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, Topeka, KS at 12:00Z on 2011-05-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3 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, Topeka, KS at 12:00Z on 2011-05-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 57 square meters per square second.19395878Sfc1 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
3 J/kg
Mixed-layer CIN
-335 J/kg
Mixed-layer LCL
637 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
57 m²/s²
0-3 km storm-relative helicity
63 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.

807 
ACUS11 KWNS 122155
SWOMCD
SPC MCD 122154
MOZ000-KSZ000-122300-

MESOSCALE DISCUSSION 0764
NWS STORM PREDICTION CENTER NORMAN OK
0454 PM CDT THU MAY 12 2011

AREAS AFFECTED...FAR EASTERN KS AND WESTERN/CENTRAL MO

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 122154Z - 122300Z

MONITORING FOR THE POSSIBILITY OF A NEW WATCH ACROSS PORTIONS OF
WESTERN/CENTRAL MO...AND PERHAPS EVEN FAR EASTERN KS. PORTIONS OF
SEVERE TSTM WATCH 293 HAVE BEEN SPATIALLY EXTENDED ACROSS SOUTHWEST
MO.

AMID A CORRIDOR OF PRE-DRYLINE CONFLUENCE...VISIBLE SATELLITE
IMAGERY REFLECTS A MATURING/DEEPENING CU FIELD ACROSS FAR SOUTHEAST
KS/SOUTHWEST MO WITH SCATTERED TSTM DEVELOPMENT ONGOING IN THESE
AREAS...WITH A SEPARATE /BUT SOMEWHAT FLATTER/ CU FIELD ALSO NOTED
OVER NORTHEAST KS IN CLOSER PROXIMITY TO THE ARCING SURFACE FRONT.
THERE IS CONCERN THAT STRONG/SEVERE TSTMS WILL CONTINUE TO
DEVELOP/EXPAND NORTHEASTWARD ACROSS FAR EASTERN KS INTO
WESTERN/CENTRAL MO THIS EVENING. SHOULD THIS OCCUR...VERY STEEP MID
LEVEL LAPSE RATES /IN CLOSE PROXIMITY TO THE CENTRAL PLAINS STACKED
CYCLONE/ AND MLCAPE ON THE ORDER OF 2000 J/KG...IN THE PRESENCE OF
MODERATELY STRONG/BUT GENERALLY UNIDIRECTIONAL WIND PROFILES...WOULD
SUPPORT SOME SUPERCELLS/ORGANIZED MULTICELLS CAPABLE OF LARGE
HAIL...DAMAGING WINDS...AND PERHAPS A BRIEF TORNADO.

..GUYER.. 05/12/2011

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

ATTN...WFO...LSX...SGF...EAX...TOP...

LAT...LON   37789361 37899491 39339562 39919497 40019375 39999281
            39619227 38899208 37889264 37789361

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 11, 7:51 PM CDTMesoscale DiscussionSPCCheyenne, Decatur, Norton, Rawlins, Sherman, Thomas84 min
May 11, 8:16 PM CDTMesoscale DiscussionSPCBrown, Nemaha59 min
May 12, 2:37 PM CDTTornado WatchSPCCloud, Jewell, Mitchell, Phillips, Republic, Smith and 1 more7 hr
May 12, 3:17 PM CDTSevere Thunderstorm WatchSPCBourbon, Cherokee, Crawford7 hr
May 12, 5:31 PM CDTSevere Thunderstorm WatchSPCLinn, Miami6 hr
May 12, 6:30 PM CDTMesoscale DiscussionSPCCherokee90 min
May 12, 1:46 PM CDTMesoscale DiscussionSPCMcDonald, Newton119 min

Nearby

Mesoscale Discussions in Missouri, 2011Mesoscale Discussions in Kansas, 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.