Alert archive / Kansas / Mesoscale Discussions in 2012

Mesoscale Discussion 540

April 14, 201225 counties in Kansas

The Storm Prediction Center issued this mesoscale discussion at Apr 14, 2012, 10:37 PM CDT for 25 counties in Kansas. It was in force for 83 min.

The area

The outline as issued.

The facts

Issued
Apr 14, 2012, 10:37 PM CDT (03:37 UTC)
Expired
Apr 15, 2012, 12:00 AM CDT
In force
83 min
Issued by
the Storm Prediction Center
All 25 counties

Butler County, KS, Chase County, KS, Clay County, KS, Coffey County, KS, Dickinson County, KS, Douglas County, KS, Franklin County, KS, Geary County, KS, Greenwood County, KS, Harvey County, KS, Jackson County, KS, Jefferson County, KS, Lyon County, KS, Marion County, KS, McPherson County, KS, Morris County, KS, Osage County, KS, Ottawa County, KS, Pottawatomie County, KS, Reno County, KS, Riley County, KS, Saline County, KS, Sedgwick County, KS, Shawnee County, KS, Wabaunsee County, KS

The radar

The Topeka radar (KTWX), 57 km from the middle of the area, began a volume at 03:38 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 00:00Z, 3.6 hours before the alert went out and 102 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 00:00Z on 2012-04-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1788 joules per kilogram.LCLEL10008507005003002001001 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 00:00Z on 2012-04-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 401 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
1788 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
665 m above ground
0-6 km bulk shear
58 kt
0-1 km storm-relative helicity
401 m²/s²
0-3 km storm-relative helicity
443 m²/s²
Significant tornado parameter
5.2
Supercell composite
17.0

Open this sounding in Storm Lab

The text

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

716 
ACUS11 KWNS 150337
SWOMCD
SPC MCD 150337 
KSZ000-150500-

MESOSCALE DISCUSSION 0540
NWS STORM PREDICTION CENTER NORMAN OK
1037 PM CDT SAT APR 14 2012

AREAS AFFECTED...CENTRAL AND EASTERN KANSAS

CONCERNING...TORNADO WATCH 170...

VALID 150337Z - 150500Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 170 CONTINUES.

GIVEN INCREASING INHIBITION FOR WARM SECTOR BOUNDARY LAYER PARCELS
...THE PERSISTENCE OF THE PAIR OF LONG-LIVED TORNADO PRODUCING
SUPERCELLS BEYOND ANOTHER HOUR OR TWO IS SOMEWHAT UNCERTAIN. 
HOWEVER...THE CELL NOW APPROACHING AREAS SOUTH OF SALINA APPEARS TO
BE AIDED BY AN AREA OF STRONGER MID-LEVEL FORCING FOR UPWARD
VERTICAL MOTION...DOWNSTREAM OF THE UPPER TROUGH NOW BEGINNING TO
LIFT ACROSS THE ROCKIES.  THIS IS EXPECTED TO SHIFT NORTHEASTWARD
ACROSS THE I-70 CORRIDOR AREA JUST EAST OF MANHATTAN THROUGH 05-06Z.
 LATEST RUC GUIDANCE SUGGESTS THAT THIS WILL COINCIDE WITH A 70 KT
SOUTHERLY 850 MB JET CORE...WHICH PROBABLY WILL MAINTAIN A HIGH
TORNADO RISK.  OTHERWISE...AS LONG AS THE SUPERCELL NOW NEAR WICHITA
MAINTAINS STRENGTH AS IT TRACKS NORTHEASTWARD NEAR THE I-35
CORRIDOR...TOWARD THE EMPORIA AREA...THE TORNADO THREAT SHOULD
REMAIN HIGH.

..KERR.. 04/15/2012

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

ATTN...WFO...EAX...TOP...ICT...

LAT...LON   39009810 39419738 39789652 39699558 39119508 38539509
            38049582 37579681 37519753 37909825 39009810

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 14, 7:15 PM CDTMesoscale DiscussionSPCButler, Chase, Dickinson, Geary, Harper, Harvey and 7 more60 min
Apr 14, 11:48 PM CDTMesoscale DiscussionSPCCoffey, Douglas, Franklin, Johnson, Leavenworth, Lyon and 2 more87 min
Apr 15, 1:37 AM CDTTornado WatchSPCAtchison, Brown, Butler, Chase, Chautauqua, Coffey and 26 more5 hr
Apr 15, 4:32 AM CDTMesoscale DiscussionSPCAllen, Anderson, Bourbon, Chautauqua, Cherokee, Coffey and 13 more88 min
Apr 15, 6:35 AM CDTMesoscale DiscussionSPCCherokee, Crawford, Labette85 min
Apr 15, 6:38 AM CDTSevere Thunderstorm WatchSPCCherokee4 hr

Nearby

Mesoscale Discussions in Kansas, 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.