Alert archive / Kansas / Mesoscale Discussions in 2017

Mesoscale Discussion 1221

July 3, 201721 counties in Kansas

The Storm Prediction Center issued this mesoscale discussion at Jul 3, 2017, 3:34 AM CDT for 21 counties in Kansas. It was in force for 116 min.

The area

The outline as issued.

The facts

Issued
Jul 3, 2017, 3:34 AM CDT (08:34 UTC)
Expired
Jul 3, 2017, 5:30 AM CDT
In force
116 min
Issued by
the Storm Prediction Center
All 21 counties

Barton County, KS, Edwards County, KS, Ellis County, KS, Ellsworth County, KS, Gove County, KS, Hodgeman County, KS, Lane County, KS, Lincoln County, KS, Logan County, KS, McPherson County, KS, Ness County, KS, Pawnee County, KS, Reno County, KS, Rice County, KS, Rush County, KS, Russell County, KS, Saline County, KS, Scott County, KS, Stafford County, KS, Thomas County, KS, Trego County, KS

The radar

The Dodge City radar (KDDC), 99 km from the middle of the area, began a volume at 08:35 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

Dodge City, (KDDC), launched 00:00Z, 8.6 hours before the alert went out and 94 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 00:00Z on 2017-07-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 723 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 00:00Z on 2017-07-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 67 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
723 J/kg
Mixed-layer CIN
-193 J/kg
Mixed-layer LCL
2226 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
67 m²/s²
0-3 km storm-relative helicity
227 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.3

Open this sounding in Storm Lab

The text

As transmitted.

440 
ACUS11 KWNS 030835
SWOMCD
SPC MCD 030834 
KSZ000-031030-

Mesoscale Discussion 1221
NWS Storm Prediction Center Norman OK
0334 AM CDT Mon Jul 03 2017

Areas affected...Portions of western and central KS

Concerning...Severe Thunderstorm Watch 391...

Valid 030834Z - 031030Z

The severe weather threat for Severe Thunderstorm Watch 391
continues.

SUMMARY...The overall severe risk for damaging winds has greatly
diminished during the overnight, while an isolated hail threat
(periodically reaching diameters around 1 inch) will remain possible
through the early morning.

DISCUSSION...The overnight/early morning surface analyses combined
with trends in mosaic radar imagery indicated a large composite
outflow boundary, attendant to the central Plains MCS, extended from
east of MHK to near EWK to south of PTT to southwest KS (Stanton
County) and southeast CO.  Mosaic radar imagery also indicated
strong/sustained storms in and just south of the extreme
south-central portion of WW 391, while a separate storm or two had
developed in northwest KS (eastern Sherman County).  

In the short-term, low-level warm advection per southerly low-level
winds atop the composite outflow boundary, combined with steep
midlevel lapse rates and strong effective bulk shear, suggests the
potential for a few additional strong to severe elevated storms. 
Hail will be the primary severe threat.  However, this severe threat
should be short-lived as the low-level jet undergoes further
weakening, with a subsequent decrease in ascent limiting
new/sustained storm development.

..Peters.. 07/03/2017

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

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

LAT...LON   37789956 37679997 38640152 39480157 39170026 39189872
            39219792 38639728 38109760 37749863 37789956

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 2, 8:04 PM CDTMesoscale DiscussionSPCCheyenne, Decatur, Graham, Norton, Phillips, Rawlins and 4 more56 min
Jul 2, 10:56 PM CDTMesoscale DiscussionSPCBarton, Ellis, Finney, Gove, Graham, Hodgeman and 12 more34 min
Jul 3, 12:02 AM CDTSevere Thunderstorm WatchSPCBarton, Cloud, Ellis, Ellsworth, Jewell, Lane and 14 more4 hr
Jul 3, 3:24 PM CDTSevere Thunderstorm WatchSPCBarber, Clark, Comanche, Meade9 hr
Jul 3, 5:49 PM CDTMesoscale DiscussionSPCCheyenne, Rawlins, Sherman, Thomas56 min

Nearby

Mesoscale Discussions in Kansas, 2017Every mesoscale discussion in 2017

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.