Alert archive / Kansas / Mesoscale Discussions in 2012

Mesoscale Discussion 381

March 29, 20128 counties in Kansas; 5 counties in Missouri; 6 counties in Nebraska

The Storm Prediction Center issued this mesoscale discussion at Mar 29, 2012, 4:54 PM CDT for 8 counties in Kansas; 5 counties in Missouri; 6 counties in Nebraska. It was in force for 36 min.

The area

The outline as issued.

The facts

Issued
Mar 29, 2012, 4:54 PM CDT (21:54 UTC)
Expired
Mar 29, 2012, 5:30 PM CDT
In force
36 min
Issued by
the Storm Prediction Center

Counties Atchison County, KS, Brown County, KS, Doniphan County, KS, Jackson County, KS, Marshall County, KS, Nemaha County, KS, Pottawatomie County, KS, Washington County, KS, Andrew County, MO, Atchison County, MO, Buchanan County, MO, Holt County, MO, Nodaway County, MO, Gage County, NE, Jefferson County, NE, Johnson County, NE, Nemaha County, NE, Pawnee County, NE, Richardson County, NE

The radar

The Topeka radar (KTWX), 103 km from the middle of the area, began a volume at 21:56 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 107 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 2012-03-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1633 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 2012-03-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 131 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
1633 J/kg
Mixed-layer CIN
-59 J/kg
Mixed-layer LCL
545 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
131 m²/s²
0-3 km storm-relative helicity
215 m²/s²
Significant tornado parameter
0.0
Supercell composite
5.1

Open this sounding in Storm Lab

The text

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

238 
ACUS11 KWNS 292155
SWOMCD
SPC MCD 292154
MOZ000-KSZ000-NEZ000-IAZ000-292230-

MESOSCALE DISCUSSION 0381
NWS STORM PREDICTION CENTER NORMAN OK
0454 PM CDT THU MAR 29 2012

AREAS AFFECTED...NERN KS/SERN NEB AND FAR NWRN MO

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY

VALID 292154Z - 292230Z

WW WILL BE NEEDED SOON AND WILL BE COORDINATED WITH AFFECTED WFOS
ACROSS NERN KS...SERN NEB AND FAR NWRN MO.

LATE AFTERNOON SURFACE ANALYSIS SHOWED AN AREA OF LOW PRESSURE OVER
SERN NEB ALONG THE KS BORDER /INVOF JEFFERSON COUNTY NEB/...WITH A
WARM FRONT EXTENDING ESEWD THROUGH THE VICINITY OF FAR SERN NEB/NERN
KS BORDER TO EAST CENTRAL MO.  THE WARM FRONT RESIDES GENERALLY N OF
I-70 IN KS.  A WIND SHIFT EXTENDED SSWWD FROM THE SURFACE LOW
THROUGH CENTRAL KS TO NWRN OK.  STRONG SURFACE HEATING ACROSS THE
WARM SECTOR HAS RESULTED IN WEAKENING OF THE CAP THAT WAS OBSERVED
ON THE SPECIAL 20Z SOUNDING AT TOP.  THUS...THE DECREASE IN SURFACE
BASED INHIBITION HAS RESULTED IN DEEPENING CU ALONG THE KS WIND
SHIFT AND ALONG THE WARM FRONT PER VISIBLE SATELLITE IMAGERY.

THE PRESENCE OF MODERATE TO STRONG INSTABILITY /MLCAPE 2000-3000 J
PER KG/ AND 30-35 KT OF EFFECTIVE SHEAR ARE SUPPORTIVE FOR ORGANIZED
STORMS.  STORMS THAT FORM AND TRACK EWD ALONG THE WARM FRONT WILL
HAVE A POTENTIAL TO PRODUCE TORNADOES GIVEN EFFECTIVE SRH OF 200-300
M2/S2.

..PETERS.. 03/29/2012

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

ATTN...WFO...EAX...OAX...TOP...GID...

LAT...LON   40069745 40529712 40599572 40539477 39769459 39689476
            39519517 39379566 39389652 39599725 40069745

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 28, 7:53 PM CDTMesoscale DiscussionSPCAllen, Anderson, Atchison, Bourbon, Brown, Clay and 24 more2 hr
Mar 28, 8:17 PM CDTSevere Thunderstorm WatchSPCAllen, Greenwood, Woodson4 hr
Mar 28, 11:21 PM CDTMesoscale DiscussionSPCAtchison, Brown, Doniphan, Nemaha84 min
Mar 29, 4:50 PM CDTMesoscale DiscussionSPCBarber, Comanche, Dickinson, Harper, Harvey, Kingman and 6 more55 min
Mar 29, 5:10 PM CDTTornado WatchSPCAtchison, Brown, Doniphan, Jackson, Jefferson, Marshall and 3 more6 hr
Mar 29, 5:30 PM CDTSevere Thunderstorm WatchSPCBarber, Butler, Chase, Coffey, Cowley, Douglas and 13 more8 hr
Mar 29, 6:58 PM CDTMesoscale DiscussionSPCAtchison, Brown, Doniphan, Jackson, Jefferson, Marshall and 4 more62 min
Mar 29, 11:53 AM CDTMesoscale DiscussionSPCCaldwell, Carroll, Chariton, Daviess, Grundy, Howard and 5 more97 min

Nearby

Mesoscale Discussions in Kansas, 2012Mesoscale Discussions in Nebraska, 2012Mesoscale Discussions in Missouri, 2012Every mesoscale discussion in 2012

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.