Alert archive / Nebraska / Mesoscale Discussions in 2015

Mesoscale Discussion 1298

July 4, 2015Logan County, Phillips County, Sedgwick County, Colorado; 19 counties in Nebraska; 7 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at Jul 4, 2015, 4:18 PM MDT for Logan County, Phillips County, Sedgwick County, Colorado; 19 counties in Nebraska; 7 counties in South Dakota. It was in force for 117 min.

The area

The outline as issued.

The facts

Issued: Jul 4, 2015, 4:18 PM MDT (22:18 UTC)
Expired: Jul 4, 2015, 6:15 PM MDT
In force: 117 min
Issued by: the Storm Prediction Center
Chance of a watch: 40%

All 29 counties

Logan County, CO, Phillips County, CO, Sedgwick County, CO, Arthur County, NE, Banner County, NE, Box Butte County, NE, Chase County, NE, Cherry County, NE, Cheyenne County, NE, Dawes County, NE, Deuel County, NE, Garden County, NE, Grant County, NE, Hooker County, NE, Keith County, NE, Kimball County, NE, McPherson County, NE, Morrill County, NE, Perkins County, NE, Scotts Bluff County, NE, Sheridan County, NE, Sioux County, NE, Bennett County, SD, Custer County, SD, Fall River County, SD, Haakon County, SD, Jackson County, SD, Oglala Lakota County, SD, Pennington County, SD

The radar

The North Platte radar (KLNX), 167 km from the middle of the area, began a volume at 22:21 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

Rapid City, SD (KRAP), launched 12:00Z, 10.3 hours before the alert went out and 226 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: 530 J/kg
Mixed-layer CIN: -231 J/kg
Mixed-layer LCL: 2014 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 41 m²/s²
0-3 km storm-relative helicity: 120 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

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
Jul 4, 5:49 PM MDT	Mesoscale Discussion	SPC	Campbell	116 min

Nearby

Mesoscale Discussions in Nebraska, 2015 Mesoscale Discussions in South Dakota, 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.