Alert archive / Kansas / Mesoscale Discussions in 2021

Mesoscale Discussion 1766

September 17, 202113 counties in Kansas; Beaver County, Oklahoma; 7 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Sep 17, 2021, 5:08 PM CDT for 13 counties in Kansas; Beaver County, Oklahoma; 7 counties in Texas. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Sep 17, 2021, 5:08 PM CDT (22:08 UTC)
Expired
Sep 17, 2021, 7:45 PM CDT
In force
3 hr
Issued by
the Storm Prediction Center
Concerning
Severe potential...watch unlikely
Chance of a watch
20%
All 21 counties

Clark County, KS, Ellis County, KS, Finney County, KS, Ford County, KS, Gray County, KS, Haskell County, KS, Hodgeman County, KS, Lane County, KS, Meade County, KS, Ness County, KS, Rush County, KS, Seward County, KS, Trego County, KS, Beaver County, OK, Collingsworth County, TX, Gray County, TX, Hemphill County, TX, Lipscomb County, TX, Ochiltree County, TX, Roberts County, TX, Wheeler County, TX

The nearest sounding before it

Dodge City, (KDDC), launched 12:00Z, 10.1 hours before the alert went out and 52 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 2021-09-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 326 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, Dodge City, at 12:00Z on 2021-09-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 119 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
326 J/kg
Mixed-layer CIN
-373 J/kg
Mixed-layer LCL
1512 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
119 m²/s²
0-3 km storm-relative helicity
372 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

Open this sounding in Storm Lab

The text

As transmitted.

209 
ACUS11 KWNS 172209
SWOMCD
SPC MCD 172208 
KSZ000-OKZ000-TXZ000-180045-

Mesoscale Discussion 1766
NWS Storm Prediction Center Norman OK
0508 PM CDT Fri Sep 17 2021

Areas affected...West-central/Southwest Kansas...Western
Oklahoma...Eastern Texas Panhandle

Concerning...Severe potential...Watch unlikely 

Valid 172208Z - 180045Z

Probability of Watch Issuance...20 percent

SUMMARY...A marginal severe threat is expected to develop over the
next few hours from west-central Kansas southward into the eastern
Texas Panhandle. The threat should remain too isolated for watch
issuance.

DISCUSSION...The latest radar imagery from Goodland shows
thunderstorms developing in northern Kansas to the north of a front
extending east-northeastward across north-central Kansas. The front
also extends southward into the Oklahoma and Texas Panhandles.
Surface dewpoints are currently in the lower 60s F to the east of
the front where MLCAPE is estimated to be in the 1000 to 1500 J/kg
range by the RAP. Additional convection has developed on the
southwestern end of the strongest instability just to the south of
Dodge City. This convection may gradually strengthen early this
evening as low-level convergence becomes enhanced along and to the
east of the front. New thunderstorms may also develop over the next
1 to 2 hours further south in the eastern Texas Panhandle. In
addition to the instability, RAP forecast soundings early this
evening show directional shear throughout the low to mid-levels with
0-6 km shear around 25 kt. This may be enough for marginally severe
storms capable of hail and strong gusty winds. The threat should
persist for a few hours this evening but will likely remain too
marginal for weather watch issuance.

..Broyles.. 09/17/2021

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

ATTN...WFO...ICT...OUN...GID...DDC...GLD...AMA...

LAT...LON   37420101 38370076 38970018 39179975 39179946 39009898
            38769893 38119945 37619966 36679979 35049975 34800037
            35020082 35470095 36420109 37420101

Nearby

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