Alert archive / Kansas / Mesoscale Discussions in 2007

Mesoscale Discussion 1817

August 20, 200727 counties in Kansas

The Storm Prediction Center issued this mesoscale discussion at Aug 20, 2007, 2:03 PM CDT for 27 counties in Kansas. It was in force for 117 min.

The area

The outline as issued.

The facts

Issued
Aug 20, 2007, 2:03 PM CDT (19:03 UTC)
Expired
Aug 20, 2007, 4:00 PM CDT
In force
117 min
Issued by
the Storm Prediction Center
All 27 counties

Barton County, KS, Cloud County, KS, Edwards County, KS, Ellis County, KS, Ellsworth County, KS, Finney County, KS, Ford County, KS, Graham County, KS, Gray County, KS, Haskell County, KS, Hodgeman County, KS, Jewell County, KS, Lane County, KS, Lincoln County, KS, Mitchell County, KS, Ness County, KS, Osborne County, KS, Ottawa County, KS, Pawnee County, KS, Phillips County, KS, Rooks County, KS, Rush County, KS, Russell County, KS, Saline County, KS, Smith County, KS, Stafford County, KS, Trego County, KS

The radar

The Dodge City radar (KDDC), 143 km from the middle of the area, began a volume at 19:06 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, 7.1 hours before the alert went out and 139 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 2007-08-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3207 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 2007-08-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 51 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
3207 J/kg
Mixed-layer CIN
-106 J/kg
Mixed-layer LCL
1415 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
51 m²/s²
0-3 km storm-relative helicity
73 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.7

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 20, 3:29 PM CDTSevere Thunderstorm WatchSPCBarton, Cloud, Edwards, Ellis, Ellsworth, Finney and 33 more7 hr
Aug 20, 5:52 PM CDTSevere Thunderstorm WatchSPCClark, Meade, Morton, Seward, Stevens6 hr
Aug 20, 6:27 PM CDTMesoscale DiscussionSPCAtchison, Brown, Dickinson, Doniphan, Douglas, Franklin and 14 more2 hr
Aug 20, 6:50 PM CDTSevere Thunderstorm WatchSPCAtchison, Brown, Clay, Dickinson, Doniphan, Douglas and 18 more6 hr

Nearby

Mesoscale Discussions in Kansas, 2007Every mesoscale discussion in 2007

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.