Alert archive / Nebraska / Mesoscale Discussions in 2016

Mesoscale Discussion 1644

September 5, 20166 counties in Nebraska; Custer County, Fall River County, Lawrence County, South Dakota; Goshen County, Niobrara County, Weston County, Wyoming

The Storm Prediction Center issued this mesoscale discussion at Sep 5, 2016, 5:09 PM MDT for 6 counties in Nebraska; Custer County, Fall River County, Lawrence County, South Dakota; Goshen County, Niobrara County, Weston County, Wyoming. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Sep 5, 2016, 5:09 PM MDT (23:09 UTC)
Expired
Sep 5, 2016, 7:45 PM MDT
In force
3 hr
Issued by
the Storm Prediction Center
Chance of a watch
20%

Counties Box Butte County, NE, Dawes County, NE, Garden County, NE, Morrill County, NE, Scotts Bluff County, NE, Sioux County, NE, Custer County, SD, Fall River County, SD, Lawrence County, SD, Goshen County, WY, Niobrara County, WY, Weston County, WY

The radar

The Rapid City radar (KUDX), 176 km from the middle of the area, began a volume at 23:11 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 12:00Z, 11.2 hours before the alert went out and 314 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-pSkew-T log-p diagram, N. Platte/Lee Bi, NE at 12:00Z on 2016-09-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1581 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, N. Platte/Lee Bi, NE at 12:00Z on 2016-09-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 137 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
1581 J/kg
Mixed-layer CIN
-229 J/kg
Mixed-layer LCL
798 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
137 m²/s²
0-3 km storm-relative helicity
136 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

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.

IssuedProductOfficeCountiesLasted
Sep 4, 6:50 PM MDTMesoscale DiscussionSPCBlaine, Buffalo, Custer, Dawson, Logan, Loup and 2 more115 min
Sep 4, 7:57 PM MDTMesoscale DiscussionSPCArthur, Chase, Cherry, Dundy, Frontier, Grant and 10 more93 min
Sep 4, 9:40 PM MDTSevere Thunderstorm WatchSPCAntelope, Blaine, Boone, Boyd, Cedar, Custer and 10 more4 hr
Sep 5, 12:10 AM MDTMesoscale DiscussionSPCDakota, Dixon, Thurston2 hr
Sep 5, 2:08 PM MDTMesoscale DiscussionSPCBlaine, Boyd, Garfield, Holt, Knox, Loup and 3 more2 hr
Sep 5, 2:30 PM MDTMesoscale DiscussionSPCFrontier, Furnas, Gosper, Harlan, Hitchcock, Phelps and 1 more90 min
Sep 5, 5:06 PM MDTMesoscale DiscussionSPCAntelope, Blaine, Boone, Buffalo, Custer, Dawson and 18 more84 min
Sep 4, 8:16 PM MDTMesoscale DiscussionSPCAurora, Beadle, Brown, Brule, Buffalo, Clark and 24 more59 min

Nearby

Mesoscale Discussions in Nebraska, 2016Mesoscale Discussions in South Dakota, 2016Mesoscale Discussions in Wyoming, 2016Every 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.