Alert archive / Kansas / Mesoscale Discussions in 2017

Mesoscale Discussion 497

April 15, 201720 counties in Kansas

The Storm Prediction Center issued this mesoscale discussion at Apr 15, 2017, 4:30 PM CDT for 20 counties in Kansas. It was in force for 90 min.

The area

The outline as issued.

The facts

Issued: Apr 15, 2017, 4:30 PM CDT (21:30 UTC)
Expired: Apr 15, 2017, 6:00 PM CDT
In force: 90 min
Issued by: the Storm Prediction Center
Chance of a watch: 40%

Counties Atchison County, KS, Barton County, KS, Clay County, KS, Dickinson County, KS, Ellsworth County, KS, Geary County, KS, Jackson County, KS, Jefferson County, KS, Lyon County, KS, Marion County, KS, McPherson County, KS, Morris County, KS, Osage County, KS, Ottawa County, KS, Pottawatomie County, KS, Rice County, KS, Riley County, KS, Saline County, KS, Shawnee County, KS, Wabaunsee County, KS

The radar

The Topeka radar (KTWX), 69 km from the middle of the area, began a volume at 21:30 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

Topeka, KS (KFOE), launched 12:00Z, 9.5 hours before the alert went out and 120 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 17 J/kg
Mixed-layer CIN: -639 J/kg
Mixed-layer LCL: 1224 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: 183 m²/s²
0-3 km storm-relative helicity: 293 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 14, 9:17 PM CDT	Mesoscale Discussion	SPC	Jewell, Norton, Phillips, Republic, Smith	88 min
Apr 15, 3:32 PM CDT	Mesoscale Discussion	SPC	Clark, Comanche, Kiowa	88 min
Apr 15, 4:00 PM CDT	Severe Thunderstorm Watch	SPC	Barber, Clark, Comanche, Edwards, Ford, Hodgeman and 4 more	7 hr
Apr 15, 5:05 PM CDT	Severe Thunderstorm Watch	SPC	Atchison, Brown, Clay, Dickinson, Doniphan, Geary and 10 more	7 hr

Nearby

Mesoscale Discussions in Kansas, 2017 Every 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.