Alert archive / Nebraska / Mesoscale Discussions in 2016

Mesoscale Discussion 1638

September 4, 201610 counties in Kansas; 16 counties in Nebraska; 4 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at Sep 4, 2016, 8:57 PM CDT for 10 counties in Kansas; 16 counties in Nebraska; 4 counties in South Dakota. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued: Sep 4, 2016, 8:57 PM CDT (01:57 UTC)
Expired: Sep 4, 2016, 10:30 PM CDT
In force: 93 min
Issued by: the Storm Prediction Center

All 30 counties

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, Wichita County, KS, Arthur County, NE, Chase County, NE, Cherry County, NE, Dundy County, NE, Frontier County, NE, Grant County, NE, Hayes County, NE, Hitchcock County, NE, Hooker County, NE, Keith County, NE, Lincoln County, NE, Logan County, NE, McPherson County, NE, Perkins County, NE, Red Willow County, NE, Thomas County, NE, Bennett County, SD, Jackson County, SD, Mellette County, SD, Todd County, SD

The radar

The North Platte radar (KLNX), 65 km from the middle of the area, began a volume at 01:59 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, 2.0 hours before the alert went out and 77 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: 2563 J/kg
Mixed-layer CIN: -22 J/kg
Mixed-layer LCL: 1408 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 118 m²/s²
0-3 km storm-relative helicity: 237 m²/s²
Significant tornado parameter: 1.5
Supercell composite: 13.6

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
Sep 5, 3:30 PM CDT	Mesoscale Discussion	SPC	Cheyenne, Decatur, Gove, Graham, Grant, Greeley and 16 more	90 min
Sep 5, 6:06 PM CDT	Mesoscale Discussion	SPC	Decatur, Rawlins	84 min
Sep 4, 7:50 PM CDT	Mesoscale Discussion	SPC	Blaine, Buffalo, Custer, Dawson, Logan, Loup and 2 more	115 min
Sep 4, 10:40 PM CDT	Severe Thunderstorm Watch	SPC	Antelope, Blaine, Boone, Boyd, Cedar, Custer and 10 more	4 hr
Sep 5, 1:10 AM CDT	Mesoscale Discussion	SPC	Dakota, Dixon, Thurston	2 hr
Sep 5, 3:08 PM CDT	Mesoscale Discussion	SPC	Blaine, Boyd, Garfield, Holt, Knox, Loup and 3 more	2 hr
Sep 5, 6:09 PM CDT	Mesoscale Discussion	SPC	Box Butte, Dawes, Garden, Morrill, Scotts Bluff, Sioux	3 hr
Sep 4, 9:16 PM CDT	Mesoscale Discussion	SPC	Aurora, Beadle, Brown, Brule, Buffalo, Clark and 24 more	59 min

Nearby

Mesoscale Discussions in Nebraska, 2016 Mesoscale Discussions in Kansas, 2016 Mesoscale Discussions in South Dakota, 2016 Every mesoscale discussion in 2016

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.