Alert archive / Kansas / Mesoscale Discussions in 2021

Mesoscale Discussion 1838

October 12, 20216 counties in Kansas; Beaver County, Ellis County, Harper County, Oklahoma; Lipscomb County, Texas

The Storm Prediction Center issued this mesoscale discussion at Oct 12, 2021, 2:29 PM CDT for 6 counties in Kansas; Beaver County, Ellis County, Harper County, Oklahoma; Lipscomb County, Texas. It was in force for 31 min.

The area

The outline as issued.

The facts

Issued
Oct 12, 2021, 2:29 PM CDT (19:29 UTC)
Expired
Oct 12, 2021, 3:00 PM CDT
In force
31 min
Issued by
the Storm Prediction Center
Concerning
Outlook upgrade

Counties Clark County, KS, Finney County, KS, Gray County, KS, Haskell County, KS, Meade County, KS, Seward County, KS, Beaver County, OK, Ellis County, OK, Harper County, OK, Lipscomb County, TX

The radar

The Dodge City radar (KDDC), 87 km from the middle of the area, began a volume at 19:33 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

Dodge City, (KDDC), launched 12:00Z, 7.5 hours before the alert went out and 90 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, Dodge City, at 12:00Z on 2021-10-12Temperature 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, Dodge City, at 12:00Z on 2021-10-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 276 square meters per square second.1939587897117136Sfc1 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
1890 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
276 m²/s²
0-3 km storm-relative helicity
277 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

750 
ACUS11 KWNS 121930
SWOMCD
SPC MCD 121929 
OKZ000-KSZ000-TXZ000-122000-

Mesoscale Discussion 1838
NWS Storm Prediction Center Norman OK
0229 PM CDT Tue Oct 12 2021

Areas affected...Portions of southwest Kansas into northwest
Oklahoma and far northeast Texas Panhandle

Concerning...Outlook upgrade 

Valid 121929Z - 122000Z

SUMMARY...An upgrade to Category 4/Moderate risk will be introduced
in the 20Z Day 1 Convective Outlook to reflect a greater risk for
strong tornadoes.

DISCUSSION...The latest high-resolution/convection allowing model
guidance consensus has been generally trending upward in the
intensity and longevity of deep, moist convection over portions of
the southern High Plains. Potential exists for multiple
discrete/semi-discrete supercells to develop ahead of a Pacific
front late this afternoon/evening. These storms are expected to
progress eastward into an ambient environment characterized by very
strong low-level shear, resulting in large, curved hodographs and
effective SRH values exceeding 400 m2/s2, especially across portions
of southwest KS/northwest OK/far northeast TX Panhandle. Here,
potential exists for at least a few intense, cyclical tornadic
supercells to develop, and a long-tracked tornado or two cannot be
ruled out. As such, portions of the central Plains will be upgraded
to Category 4/Moderate risk in the upcoming 20Z Day 1 Convective
Outlook.

..Squitieri/Grams.. 10/12/2021

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

ATTN...WFO...OUN...DDC...AMA...

LAT...LON   37820131 38210130 38260110 38130068 37789998 37409977
            36969957 36579950 36309955 36119968 35969986 35850027
            35900047 36520078 37820131

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Oct 12, 3:08 PM CDTMesoscale DiscussionSPCCheyenne, Finney, Grant, Gray, Greeley, Hamilton and 14 more97 min
Oct 12, 3:46 PM CDTTornado WatchSPCCheyenne, Decatur, Finney, Gove, Graham, Grant and 20 more7 hr
Oct 12, 6:22 PM CDTMesoscale DiscussionSPCCheyenne, Finney, Grant, Greeley, Hamilton, Haskell and 7 more83 min
Oct 12, 3:14 PM CDTMesoscale DiscussionSPCBeckham, Ellis, Greer, Harmon, Jackson, Roger Mills3 hr
Oct 12, 5:34 PM CDTTornado WatchSPCBeaver, Beckham, Blaine, Caddo, Canadian, Comanche and 18 more5 hr

Nearby

Mesoscale Discussions in Kansas, 2021Mesoscale Discussions in Oklahoma, 2021Mesoscale Discussions in Texas, 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.