Alert archive / Kansas / Mesoscale Discussions in 2021

Mesoscale Discussion 725

May 24, 2021Decatur County, Norton County, Kansas

The Storm Prediction Center issued this mesoscale discussion at May 24, 2021, 6:39 PM CDT for Decatur County, Norton County, Kansas. It was in force for 36 min.

The area

The outline as issued.

The facts

Issued
May 24, 2021, 6:39 PM CDT (23:39 UTC)
Expired
May 24, 2021, 7:15 PM CDT
In force
36 min
Issued by
the Storm Prediction Center
Concerning
Severe thunderstorm watch 200

Counties Decatur County, KS, Norton County, KS

The radar

The Goodland radar (KGLD), 138 km from the middle of the area, began a volume at 23:41 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, 11.7 hours before the alert went out and 163 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, N. Platte/Lee Bi, NE at 12:00Z on 2021-05-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, N. Platte/Lee Bi, NE at 12:00Z on 2021-05-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -95 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1599 m above ground
0-6 km bulk shear
60 kt
0-1 km storm-relative helicity
-95 m²/s²
0-3 km storm-relative helicity
111 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

531 
ACUS11 KWNS 242340
SWOMCD
SPC MCD 242339 
KSZ000-NEZ000-250015-

Mesoscale Discussion 0725
NWS Storm Prediction Center Norman OK
0639 PM CDT Mon May 24 2021

Areas affected...Portions of Northwest/north-central Kansas

Concerning...Severe Thunderstorm Watch 200...

Valid 242339Z - 250015Z

The severe weather threat for Severe Thunderstorm Watch 200
continues.

SUMMARY...The potential for a tornado will continue from along the
Sheridan/Decatur County line into the Norton/Graham County line.
Downstream backing winds and temperature/dewpoint increases are
supportive.

DISCUSSION...A tornado has been confirmed near Selden, KS with a
supercell that has had relatively persistent 50-60 kt rotational
velocity on KGLD 0.5 degree velocity. The environment ahead of the
storm is expected to continue to support tornadic potential as winds
at Hill City and Norton have backed to east-southeast and
strengthened. Temperatures and dewpoints have also risen slightly. A
complicating factor could be developing convection in the inflow
region of the storm, now evident in Graham County. This could
potentially reduce tornado potential quicker than expected.

..Wendt.. 05/24/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...GID...GLD...

LAT...LON   39720074 39980046 40079956 39759940 39539959 39420007
            39430062 39720074

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 23, 7:32 PM CDTMesoscale DiscussionSPCMorton118 min
May 23, 7:53 PM CDTMesoscale DiscussionSPCCheyenne, Sherman67 min
May 23, 8:12 PM CDTSevere Thunderstorm WatchSPCCheyenne, Decatur, Gove, Graham, Greeley, Logan and 7 more5 hr
May 23, 9:56 PM CDTMesoscale DiscussionSPCCheyenne, Decatur, Logan, Rawlins, Sheridan, Sherman and 2 more2 hr
May 24, 1:00 PM CDTMesoscale DiscussionSPCFinney, Gove, Grant, Gray, Greeley, Hamilton and 12 more2 hr
May 24, 1:29 PM CDTTornado WatchSPCCheyenne, Decatur, Finney, Gove, Graham, Grant and 18 more9 hr
May 24, 3:42 PM CDTMesoscale DiscussionSPCGove, Logan, Rawlins, Sheridan, Thomas63 min
May 24, 5:37 PM CDTMesoscale DiscussionSPCDecatur, Finney, Gove, Grant, Hamilton, Kearny and 7 more113 min

Nearby

Mesoscale Discussions in Kansas, 2021Every mesoscale discussion in 2021

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.