Alert archive / Colorado / Mesoscale Discussions in 2011

Mesoscale Discussion 2082

August 29, 201111 counties in Colorado; 8 counties in Nebraska; 4 counties in Wyoming

The Storm Prediction Center issued this mesoscale discussion at Aug 29, 2011, 1:05 PM MDT for 11 counties in Colorado; 8 counties in Nebraska; 4 counties in Wyoming. It was in force for 85 min.

The area

The outline as issued.

The facts

Issued: Aug 29, 2011, 1:05 PM MDT (19:05 UTC)
Expired: Aug 29, 2011, 2:30 PM MDT
In force: 85 min
Issued by: the Storm Prediction Center

All 23 counties

Adams County, CO, Arapahoe County, CO, Elbert County, CO, Kit Carson County, CO, Logan County, CO, Morgan County, CO, Phillips County, CO, Sedgwick County, CO, Washington County, CO, Weld County, CO, Yuma County, CO, Banner County, NE, Box Butte County, NE, Cheyenne County, NE, Deuel County, NE, Kimball County, NE, Morrill County, NE, Scotts Bluff County, NE, Sioux County, NE, Goshen County, WY, Laramie County, WY, Niobrara County, WY, Platte County, WY

The radar

The Cheyenne radar (KCYS), 72 km from the middle of the area, began a volume at 19:05 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

Denver, CO (KDNR), launched 12:00Z, 7.1 hours before the alert went out and 144 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: 157 J/kg
Mixed-layer CIN: -137 J/kg
Mixed-layer LCL: 1100 m above ground
0-6 km bulk shear: 14 kt
0-1 km storm-relative helicity: 21 m²/s²
0-3 km storm-relative helicity: 76 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
Aug 29, 1:52 PM MDT	Mesoscale Discussion	SPC	Big Horn, Johnson, Sheridan	83 min
Aug 29, 2:34 PM MDT	Severe Thunderstorm Watch	SPC	Campbell, Crook, Sheridan, Weston	6 hr
Aug 29, 5:09 PM MDT	Mesoscale Discussion	SPC	Crook	96 min

Nearby

Mesoscale Discussions in Colorado, 2011 Mesoscale Discussions in Nebraska, 2011 Mesoscale Discussions in Wyoming, 2011 Every mesoscale discussion in 2011

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.