Alert archive / Kansas / Mesoscale Discussions in 2021

Mesoscale Discussion 561

May 8, 202113 counties in Kansas; Webster County, Nebraska

The Storm Prediction Center issued this mesoscale discussion at May 8, 2021, 3:24 PM CDT for 13 counties in Kansas; Webster County, Nebraska. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
May 8, 2021, 3:24 PM CDT (20:24 UTC)
Expired
May 8, 2021, 5:30 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
Concerning
Severe potential...watch likely
Chance of a watch
80%

Counties Barton County, KS, Ellis County, KS, Ellsworth County, KS, Jewell County, KS, Lincoln County, KS, Mitchell County, KS, Osborne County, KS, Pawnee County, KS, Rice County, KS, Rooks County, KS, Rush County, KS, Russell County, KS, Smith County, KS, Webster County, NE

The radar

The Grand Island radar (KUEX), 144 km from the middle of the area, began a volume at 20:26 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, 8.4 hours before the alert went out and 175 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 2021-05-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Dodge City, at 12:00Z on 2021-05-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -29 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
2 J/kg
Mixed-layer CIN
-649 J/kg
Mixed-layer LCL
2080 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
-29 m²/s²
0-3 km storm-relative helicity
52 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

690 
ACUS11 KWNS 082025
SWOMCD
SPC MCD 082024 
KSZ000-NEZ000-082230-

Mesoscale Discussion 0561
NWS Storm Prediction Center Norman OK
0324 PM CDT Sat May 08 2021

Areas affected...portions of central KS and extreme south-central NE

Concerning...Severe potential...Watch likely 

Valid 082024Z - 082230Z

Probability of Watch Issuance...80 percent

SUMMARY...Isolated severe thunderstorms are expected to develop in
the 5-7 pm CDT/22z-00z time frame, with a risk for primarily large
hail and damaging winds. Observational trends are being monitored
and a watch is likely to 22z.

DISCUSSION...Latest visible satellite imagery shows a high-based
cumulus field becoming better established over portions of southwest
and central KS near a triple point north of Dodge City. A warm front
extends north/east from the triple point across northern KS, while a
cold front continues moving southward over western KS.  Strong
heating/mixing of mid-upper 50s surface dew points has resulted in
moderate-strong MLCAPE beneath an EML within the warm sector, with
further erosion of MLCINH contributing to thunderstorm development
in the 22z-00z time frame as a mid-level shortwave trough approaches
from the west. 

Isolated supercell storms developing initially near the triple point
will move east-northeast in the vicinity of the warm front with a
risk for primarily large hail.  Damaging winds will become more
likely with time, and some risk for a tornado may also exist,
especially with discrete storms near the warm front.  Thunderstorm
coverage should increase through early evening along the cold front
as it advances eastward over north-central KS. 

Trends continue to be monitored and a watch is likely by 22z.

..Bunting/Thompson.. 05/08/2021

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

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

LAT...LON   37889922 37939965 38319993 39099957 39599931 39979920
            40209872 40189814 39969796 39549797 39279795 38979795
            38719796 38239814 37889922

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 8, 4:00 PM CDTSevere Thunderstorm WatchSPCBarton, Ellis, Ellsworth, Hodgeman, Jewell, Lincoln and 11 more6 hr
May 8, 6:06 PM CDTMesoscale DiscussionSPCAtchison, Barton, Brown, Clay, Cloud, Dickinson and 29 more114 min
May 8, 6:30 PM CDTTornado WatchSPCClay, Cloud, Dickinson, Douglas, Franklin, Geary and 12 more7 hr
May 8, 6:42 PM CDTSevere Thunderstorm WatchSPCAtchison, Brown, Doniphan, Marshall, Nemaha6 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.