Alert archive / North Dakota / Mesoscale Discussions in 2011

Mesoscale Discussion 1807

July 31, 20114 counties in North Dakota

The Storm Prediction Center issued this mesoscale discussion at Jul 31, 2011, 7:16 PM MDT for 4 counties in North Dakota. It was in force for 89 min.

The area

The outline as issued.

The facts

Issued
Jul 31, 2011, 7:16 PM MDT (01:16 UTC)
Expired
Jul 31, 2011, 8:45 PM MDT
In force
89 min
Issued by
the Storm Prediction Center

Counties Adams County, ND, Grant County, ND, Morton County, ND, Sioux County, ND

The radar

The Bismarck radar (KBIS), 115 km from the middle of the area, began a volume at 01:20 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

Bismarck Municip, ND (KBIS), launched 00:00Z, 1.3 hours before the alert went out and 118 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, Bismarck Municip, ND at 00:00Z on 2011-08-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 5391 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, Bismarck Municip, ND at 00:00Z on 2011-08-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 111 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
5391 J/kg
Mixed-layer CIN
-56 J/kg
Mixed-layer LCL
1026 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
111 m²/s²
0-3 km storm-relative helicity
243 m²/s²
Significant tornado parameter
5.9
Supercell composite
30.6

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
Jul 31, 9:26 PM MDTSevere Thunderstorm WatchSPCBarnes, Benson, Burleigh, Cass, Cavalier, Dickey and 25 more8 hr
Jul 31, 11:35 PM MDTMesoscale DiscussionSPCBarnes, Burleigh, Cass, Eddy, Emmons, Foster and 12 more85 min
Aug 1, 1:31 AM MDTMesoscale DiscussionSPCCass, Grand Forks, Griggs, Nelson, Steele, Traill and 1 more89 min
Aug 1, 3:57 AM MDTSevere Thunderstorm WatchSPCBarnes, Cass, Dickey, Eddy, Foster, Griggs and 11 more7 hr
Aug 1, 10:52 AM MDTSevere Thunderstorm WatchSPCBarnes, Cass, Grand Forks, Griggs, Nelson, Ransom and 4 more7 hr
Aug 1, 12:33 PM MDTMesoscale DiscussionSPCAdams, Burleigh, Emmons, Grant, Hettinger, Kidder and 10 more57 min
Aug 1, 1:19 PM MDTSevere Thunderstorm WatchSPCAdams, Bowman, Burleigh, Emmons, Grant, Hettinger and 10 more6 hr
Aug 1, 2:53 PM MDTMesoscale DiscussionSPCBarnes, Cass, Grand Forks, Griggs, Nelson, Ransom and 3 more67 min
Aug 1, 4:57 PM MDTMesoscale DiscussionSPCAdams, Barnes, Benson, Burleigh, Cavalier, Dickey and 23 more2 hr
Aug 1, 5:10 PM MDTMesoscale DiscussionSPCAdams, Barnes, Benson, Burleigh, Cavalier, Dickey and 23 more2 hr

Nearby

Mesoscale Discussions in North Dakota, 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.