Alert archive / Kansas / Mesoscale Discussions in 2021

Mesoscale Discussion 479

May 2, 202138 counties in Kansas; 8 counties in Nebraska

The Storm Prediction Center issued this mesoscale discussion at May 2, 2021, 5:26 PM CDT for 38 counties in Kansas; 8 counties in Nebraska. It was in force for 64 min.

The area

The outline as issued.

The facts

Issued
May 2, 2021, 5:26 PM CDT (22:26 UTC)
Expired
May 2, 2021, 6:30 PM CDT
In force
64 min
Issued by
the Storm Prediction Center
Concerning
Severe potential...severe thunderstorm watch likely
Chance of a watch
95%
All 46 counties

Barton County, KS, Cheyenne County, KS, Decatur County, KS, Edwards County, KS, Ellis County, KS, Ellsworth County, KS, Finney County, KS, Gove County, KS, Graham County, KS, Greeley County, KS, Hamilton County, KS, Hodgeman County, KS, Jewell County, KS, Kearny County, KS, Lane County, KS, Lincoln County, KS, Logan County, KS, Mitchell County, KS, Ness County, KS, Norton County, KS, Osborne County, KS, Pawnee County, KS, Phillips County, KS, Rawlins County, KS, Reno County, KS, Rice County, KS, Rooks County, KS, Rush County, KS, Russell County, KS, Scott County, KS, Sheridan County, KS, Sherman County, KS, Smith County, KS, Stafford County, KS, Thomas County, KS, Trego County, KS, Wallace County, KS, Wichita County, KS, Dundy County, NE, Franklin County, NE, Furnas County, NE, Harlan County, NE, Hitchcock County, NE, Nuckolls County, NE, Red Willow County, NE, Webster County, NE

The radar

The Goodland radar (KGLD), 114 km from the middle of the area, began a volume at 22:26 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, 10.4 hours before the alert went out and 173 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 2021-05-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 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 2021-05-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 199 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
1 J/kg
Mixed-layer CIN
-668 J/kg
Mixed-layer LCL
1278 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
199 m²/s²
0-3 km storm-relative helicity
207 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

114 
ACUS11 KWNS 022227
SWOMCD
SPC MCD 022226 
KSZ000-NEZ000-022330-

Mesoscale Discussion 0479
NWS Storm Prediction Center Norman OK
0526 PM CDT Sun May 02 2021

Areas affected...Portions of western/central KS

Concerning...Severe potential...Severe Thunderstorm Watch likely 

Valid 022226Z - 022330Z

Probability of Watch Issuance...95 percent

SUMMARY...Severe threat, including the potential for significant
severe wind gusts, will likely continue to increase early this
evening. A Severe Thunderstorm Watch will likely be issued.

DISCUSSION...Convection has recently begun to form along a surface
front in north-central KS as low-level convergence gradually
increases late this afternoon. Additional robust storm development
will likely occur/form along the KS/CO border and subsequently
spread eastward. As this activity encounters increasing low-level
moisture and rather well mixed airmass, damaging/severe wind gusts
will likely become the main threat very quickly. Isolated large hail
may also occur. Given the deeply mixed boundary layer and convection
likely to focus along the surface front and grow upscale quickly,
significant severe wind gusts appear possible. A Severe Thunderstorm
Watch will be issued soon to address this increasing threat.

..Gleason/Thompson.. 05/02/2021

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

ATTN...WFO...ICT...GID...DDC...GLD...

LAT...LON   40290201 40299797 37809794 37750198 40290201

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 2, 3:45 PM CDTMesoscale DiscussionSPCCheyenne, Decatur, Greeley, Logan, Rawlins, Sheridan and 4 more90 min
May 2, 5:41 PM CDTSevere Thunderstorm WatchSPCBarton, Cheyenne, Decatur, Edwards, Ellis, Ellsworth and 34 more6 hr

Nearby

Mesoscale Discussions in Kansas, 2021Mesoscale Discussions in Nebraska, 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.