Alert archive / North Dakota / Mesoscale Discussions in 2011

Mesoscale Discussion 2006

August 18, 201124 counties in Minnesota; 33 counties in North Dakota; 26 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at Aug 18, 2011, 3:43 PM CDT for 24 counties in Minnesota; 33 counties in North Dakota; 26 counties in South Dakota. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued
Aug 18, 2011, 3:43 PM CDT (20:43 UTC)
Expired
Aug 18, 2011, 5:15 PM CDT
In force
92 min
Issued by
the Storm Prediction Center
All 83 counties

Becker County, MN, Big Stone County, MN, Chippewa County, MN, Clay County, MN, Clearwater County, MN, Douglas County, MN, Grant County, MN, Kittson County, MN, Lac qui Parle County, MN, Lincoln County, MN, Mahnomen County, MN, Marshall County, MN, Norman County, MN, Otter Tail County, MN, Pennington County, MN, Polk County, MN, Pope County, MN, Red Lake County, MN, Roseau County, MN, Stevens County, MN, Swift County, MN, Traverse County, MN, Wilkin County, MN, Yellow Medicine County, MN, Barnes County, ND, Benson County, ND, Burleigh County, ND, Cass County, ND, Cavalier County, ND, Dickey County, ND, Eddy County, ND, Emmons County, ND, Foster County, ND, Grand Forks County, ND, Grant County, ND, Griggs County, ND, Kidder County, ND, LaMoure County, ND, Logan County, ND, McIntosh County, ND, Morton County, ND, Nelson County, ND, Oliver County, ND, Pembina County, ND, Pierce County, ND, Ramsey County, ND, Ransom County, ND, Richland County, ND, Sargent County, ND, Sheridan County, ND, Sioux County, ND, Steele County, ND, Stutsman County, ND, Towner County, ND, Traill County, ND, Walsh County, ND, Wells County, ND, Beadle County, SD, Brookings County, SD, Brown County, SD, Campbell County, SD, Clark County, SD, Codington County, SD, Corson County, SD, Day County, SD, Deuel County, SD, Dewey County, SD, Edmunds County, SD, Faulk County, SD, Grant County, SD, Hamlin County, SD, Hand County, SD, Hughes County, SD, Hyde County, SD, Kingsbury County, SD, Marshall County, SD, McPherson County, SD, Potter County, SD, Roberts County, SD, Spink County, SD, Stanley County, SD, Sully County, SD, Walworth County, SD

The radar

The Aberdeen radar (KABR), 93 km from the middle of the area, began a volume at 20:44 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Aberdeen, SD (KABR), launched 12:00Z, 8.7 hours before the alert went out and 153 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, Aberdeen, SD at 12:00Z on 2011-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1339 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, Aberdeen, SD at 12:00Z on 2011-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 115 square meters per square second.1939587897Sfc1 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
1339 J/kg
Mixed-layer CIN
-177 J/kg
Mixed-layer LCL
1070 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
115 m²/s²
0-3 km storm-relative helicity
79 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.8

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.

IssuedProductOfficeCountiesLasted
Aug 18, 4:45 PM CDTSevere Thunderstorm WatchSPCDickey, Emmons, LaMoure, Logan, McIntosh, Sioux4 hr
Aug 17, 9:18 PM CDTMesoscale DiscussionSPCMellette, Todd, Tripp57 min
Aug 18, 12:31 PM CDTMesoscale DiscussionSPCBon Homme, Clay, Hutchinson, Union, Yankton89 min
Aug 18, 1:27 PM CDTSevere Thunderstorm WatchSPCClay, Union, Yankton8 hr
Aug 18, 6:18 PM CDTMesoscale DiscussionSPCUnion27 min

Nearby

Mesoscale Discussions in North Dakota, 2011Mesoscale Discussions in South Dakota, 2011Mesoscale Discussions in Minnesota, 2011Every 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.