Alert archive / Nebraska / Mesoscale Discussions in 2015

Mesoscale Discussion 371

April 18, 20156 counties in Colorado; 9 counties in Kansas; 16 counties in Nebraska

The Storm Prediction Center issued this mesoscale discussion at Apr 18, 2015, 7:27 PM MDT for 6 counties in Colorado; 9 counties in Kansas; 16 counties in Nebraska. It was in force for 63 min.

The area

The outline as issued.

The facts

Issued: Apr 18, 2015, 7:27 PM MDT (01:27 UTC)
Expired: Apr 18, 2015, 8:30 PM MDT
In force: 63 min
Issued by: the Storm Prediction Center

All 31 counties

Cheyenne County, CO, Kit Carson County, CO, Logan County, CO, Phillips County, CO, Sedgwick County, CO, Yuma County, CO, Cheyenne County, KS, Decatur County, KS, Gove County, KS, Logan County, KS, Rawlins County, KS, Sheridan County, KS, Sherman County, KS, Thomas County, KS, Wallace County, KS, Arthur County, NE, Chase County, NE, Cheyenne County, NE, Deuel County, NE, Dundy County, NE, Frontier County, NE, Garden County, NE, Hayes County, NE, Hitchcock County, NE, Keith County, NE, Lincoln County, NE, Logan County, NE, McPherson County, NE, Morrill County, NE, Perkins County, NE, Red Willow County, NE

The radar

The Goodland radar (KGLD), 60 km from the middle of the area, began a volume at 01:27 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

N. Platte/Lee Bi, NE (KLBF), launched 00:00Z, 1.5 hours before the alert went out and 179 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: 88 J/kg
Mixed-layer CIN: -25 J/kg
Mixed-layer LCL: 2027 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 44 m²/s²
0-3 km storm-relative helicity: 131 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

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.

Issued	Product	Office	Counties	Lasted
Apr 18, 7:11 PM MDT	Mesoscale Discussion	SPC	Barber, Barton, Clark, Comanche, Edwards, Ellis and 24 more	64 min
Apr 19, 11:43 AM MDT	Mesoscale Discussion	SPC	Chautauqua, Cherokee, Cowley, Crawford, Elk, Labette and 4 more	2 hr

Nearby

Mesoscale Discussions in Nebraska, 2015 Mesoscale Discussions in Kansas, 2015 Mesoscale Discussions in Colorado, 2015 Every mesoscale discussion in 2015

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.