Alert archive / Nebraska / Mesoscale Discussions in 2018

Mesoscale Discussion 504

May 23, 20185 states

The Storm Prediction Center issued this mesoscale discussion at May 23, 2018, 5:07 PM MDT for 5 states. It was in force for 83 min.

The area

The outline as issued.

The facts

Issued: May 23, 2018, 5:07 PM MDT (23:07 UTC)
Expired: May 23, 2018, 6:30 PM MDT
In force: 83 min
Issued by: the Storm Prediction Center

All 36 counties

Larimer County, CO, Logan County, CO, Morgan County, CO, Phillips County, CO, Sedgwick County, CO, Weld County, CO, Carter County, MT, Banner County, NE, Box Butte County, NE, Cheyenne County, NE, Dawes County, NE, Deuel County, NE, Garden County, NE, Kimball County, NE, Morrill County, NE, Scotts Bluff County, NE, Sheridan County, NE, Sioux County, NE, Butte County, SD, Custer County, SD, Fall River County, SD, Harding County, SD, Lawrence County, SD, Meade County, SD, Oglala Lakota County, SD, Pennington County, SD, Perkins County, SD, Albany County, WY, Campbell County, WY, Converse County, WY, Crook County, WY, Goshen County, WY, Laramie County, WY, Niobrara County, WY, Platte County, WY, Weston County, WY

The radar

The Cheyenne radar (KCYS), 114 km from the middle of the area, began a volume at 23:07 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, 11.1 hours before the alert went out and 248 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 964 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 86 m²/s²
0-3 km storm-relative helicity: 91 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
May 23, 1:00 PM MDT	Mesoscale Discussion	SPC	Adams, Broomfield, Morgan, Weld	2 hr
May 23, 1:31 PM MDT	Severe Thunderstorm Watch	SPC	Logan, Morgan, Phillips, Sedgwick, Weld	7 hr
May 23, 2:34 PM MDT	Mesoscale Discussion	SPC	Big Horn, Carter, Custer, Fallon, Powder River, Rosebud and 1 more	116 min
May 23, 1:36 PM MDT	Mesoscale Discussion	SPC	Aurora, Beadle, Brown, Brule, Buffalo, Campbell and 16 more	114 min

Nearby

Mesoscale Discussions in Nebraska, 2018 Mesoscale Discussions in South Dakota, 2018 Mesoscale Discussions in Wyoming, 2018 Every mesoscale discussion in 2018

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.