Alert archive / Kansas / Mesoscale Discussions in 2012

Mesoscale Discussion 2008

September 30, 201230 counties in Kansas; 24 counties in Nebraska

The Storm Prediction Center issued this mesoscale discussion at Sep 30, 2012, 3:50 PM CDT for 30 counties in Kansas; 24 counties in Nebraska. It was in force for 85 min.

The area

The outline as issued.

The facts

Issued: Sep 30, 2012, 3:50 PM CDT (20:50 UTC)
Expired: Sep 30, 2012, 5:15 PM CDT
In force: 85 min
Issued by: the Storm Prediction Center
Chance of a watch: 5%

All 54 counties

Cheyenne County, KS, Decatur County, KS, Finney County, KS, Ford County, KS, Gove County, KS, Graham County, KS, Grant County, KS, Gray County, KS, Greeley County, KS, Hamilton County, KS, Haskell County, KS, Hodgeman County, KS, Kearny County, KS, Lane County, KS, Logan County, KS, Meade County, KS, Ness County, KS, Norton County, KS, Phillips County, KS, Rawlins County, KS, Scott County, KS, Seward County, KS, Sheridan County, KS, Sherman County, KS, Stanton County, KS, Stevens County, KS, Thomas County, KS, Trego County, KS, Wallace County, KS, Wichita County, KS, Blaine County, NE, Brown County, NE, Chase County, NE, Cherry County, NE, Custer County, NE, Dawson County, NE, Dundy County, NE, Frontier County, NE, Furnas County, NE, Gosper County, NE, Harlan County, NE, Hayes County, NE, Hitchcock County, NE, Hooker County, NE, Keith County, NE, Lincoln County, NE, Logan County, NE, Loup County, NE, McPherson County, NE, Perkins County, NE, Phelps County, NE, Red Willow County, NE, Rock County, NE, Thomas County, NE

The radar

The Goodland radar (KGLD), 148 km from the middle of the area, began a volume at 20:51 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 nearest sounding before it

N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 8.8 hours before the alert went out and 81 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 340 J/kg
Mixed-layer CIN: -223 J/kg
Mixed-layer LCL: 881 m above ground
0-6 km bulk shear: 7 kt
0-1 km storm-relative helicity: 8 m²/s²
0-3 km storm-relative helicity: 34 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.

717 
ACUS11 KWNS 302050
SWOMCD
SPC MCD 302050 
NEZ000-KSZ000-COZ000-302215-

MESOSCALE DISCUSSION 2008
NWS STORM PREDICTION CENTER NORMAN OK
0350 PM CDT SUN SEP 30 2012

AREAS AFFECTED...CNTRL NEB INTO WRN KS

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 302050Z - 302215Z

PROBABILITY OF WATCH ISSUANCE...5 PERCENT

SUMMARY...ISOLATED TO SCATTERED THUNDERSTORMS WILL CONTINUE TO
DEVELOP THROUGH THE AFTERNOON AND MOVE TO THE S/SE. A SMALL WINDOW
FOR MARGINALLY SEVERE WIND/HAIL WILL EXIST UNTIL SUNSET. CONVECTION
IS EXPECTED TO WEAKEN THEREAFTER. A WW IS NOT EXPECTED.

DISCUSSION...ISOLATED TO SCATTERED THUNDERSTORMS WILL CONTINUE TO
DEVELOP THIS AFTERNOON IN VICINITY OF SFC TROUGH. TEMPERATURES HAVE
WARMED INTO THE MID 70S TO LOW 80S...RESULTING IN STEEP LOW LEVEL
LAPSE RATES AND MLCAPE VALUES OF 500-1500 J/KG. GENERALLY WEAK DEEP
LAYER SHEAR AND LACK OF UPPER FORCING FOR ASCENT WILL LIMIT
COVERAGE/ORGANIZATION OF CONVECTION. HOWEVER...AFOREMENTIONED STEEP
LAPSE RATES AND A DRY BOUNDARY LAYER WILL LEAD TO AT LEAST A LOW
CHANCE OF A FEW STRONG WIND GUSTS AND POSSIBLY ISOLATED LARGE HAIL
IN STRONGEST CELLS. ANY MARGINAL THREAT IS ONLY EXPECTED TO LAST FOR
ABOUT 3-4 HOURS THIS AFTERNOON BEFORE DIURNAL COOLING LEADS TO
BOUNDARY LAYER STABILIZATION. A WW IS NOT EXPECTED.

..LEITMAN/HART.. 09/30/2012

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

ATTN...WFO...GID...LBF...DDC...GLD...PUB...

LAT...LON   42960028 42769957 42289924 41529904 37679967 37229986
            37120097 37270231 38530220 40400190 41810157 42770106
            42960028

Nearby

Mesoscale Discussions in Kansas, 2012 Mesoscale Discussions in Nebraska, 2012 Every 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.