Alert archive / North Dakota / Mesoscale Discussions in 2011

Mesoscale Discussion 708

May 10, 2011Wilkin County, Minnesota; 21 counties in North Dakota; 7 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at May 10, 2011, 1:56 AM CDT for Wilkin County, Minnesota; 21 counties in North Dakota; 7 counties in South Dakota. It was in force for 94 min.

The area

The outline as issued.

The facts

Issued: May 10, 2011, 1:56 AM CDT (06:56 UTC)
Expired: May 10, 2011, 3:30 AM CDT
In force: 94 min
Issued by: the Storm Prediction Center

All 29 counties

Wilkin County, MN, Adams County, ND, Barnes County, ND, Burleigh County, ND, Cass County, ND, Emmons County, ND, Foster County, ND, Grant County, ND, Griggs County, ND, Kidder County, ND, LaMoure County, ND, Logan County, ND, Morton County, ND, Ransom County, ND, Richland County, ND, Sargent County, ND, Sheridan County, ND, Sioux County, ND, Steele County, ND, Stutsman County, ND, Traill County, ND, Wells County, ND, Butte County, SD, Corson County, SD, Dewey County, SD, Meade County, SD, Perkins County, SD, Stanley County, SD, Ziebach County, SD

The radar

The Aberdeen radar (KABR), 116 km from the middle of the area, began a volume at 06:59 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, 6.9 hours before the alert went out and 131 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: 792 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 39 m²/s²
0-3 km storm-relative helicity: 354 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

863 
ACUS11 KWNS 100657
SWOMCD
SPC MCD 100656
MNZ000-SDZ000-NDZ000-100830-

MESOSCALE DISCUSSION 0708
NWS STORM PREDICTION CENTER NORMAN OK
0156 AM CDT TUE MAY 10 2011

AREAS AFFECTED...NWRN SD AND PARTS OF SRN/CENTRAL AND ERN ND

CONCERNING...SEVERE THUNDERSTORM WATCH 267...

VALID 100656Z - 100830Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 267
CONTINUES.

GIVEN CURRENT CONVECTIVE TRENDS ACROSS NWRN SD SHOWING A LOWER
NUMBER OF STRONGER STORMS...WW 267 WILL BE ALLOWED TO EXPIRE AS
SCHEDULED AT 08Z.  UNTIL THEN...AND ALSO THROUGH THE OVERNIGHT
ACROSS SRN/CENTRAL AND ERN ND...ISOLATED SEVERE STORMS REMAIN
POSSIBLE WITH HAIL BEING THE PRIMARY THREAT FROM THE ELEVATED
ACTIVITY.

RECENT WATER VAPOR IMAGERY SHOWED A SHORTWAVE TROUGH LOCATED OVER
ERN WY...WITH THIS FEATURE EXPECTED TO MOVE INTO THE WRN DAKOTAS BY
12Z RESULTING IN THE STRONGEST FORCING ALOFT TO AFFECT THE WRN
DAKOTAS.  ALTHOUGH EFFECTIVE BULK SHEAR REMAINS STRONG /AROUND 50
KT/ ACROSS THE VALID PART OF WW 267 TO SUPPORT ORGANIZED
STORMS...WEAKENING AVAILABLE INSTABILITY IN THIS AREA SUGGESTS THE
OBSERVED DECREASE IN STRONGER UPDRAFTS SHOULD PERSIST.

MEANWHILE...A 50 KT SSELY LLJ EXTENDS ACROSS ERN SD WITH STRONG LOW
LEVEL WAA EXPECTED TO DEVELOP NWD INTO ND OVERNIGHT/EARLY THIS
MORNING AS THE ABOVE MENTIONED TROUGH AND EWD EXTENDING WARM FRONT
SPREAD NWD.  THE LLJ WILL MAINTAIN A FEED OF MODERATE INSTABILITY
INTO CENTRAL/ERN ND.  THIS COMBINED WITH THE LOW LEVEL WAA WILL
SUPPORT TSTMS DEVELOPING/MOVING NWD...BUT GIVEN STRONGER FORCING
ALOFT REMAINING WEST OVER THE WRN DAKOTAS...THE OVERALL COVERAGE OF
STRONGER STORMS IS NOT EXPECTED TO BE SUFFICIENT TO WARRANT A NEW
WATCH.

..PETERS.. 05/10/2011

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...FGF...ABR...BIS...UNR...

LAT...LON   44290097 44360256 44940367 45930326 47600037 47719841
            47599706 46269641 45879640 46069758 46369902 45860011
            44690047 44440040 44290097

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 10, 5:10 PM CDT	Mesoscale Discussion	SPC	Anoka, Becker, Benton, Blue Earth, Carver, Chisago and 33 more	95 min
May 10, 5:53 PM CDT	Tornado Watch	SPC	Aitkin, Anoka, Benton, Carlton, Carver, Cass and 18 more	6 hr
May 9, 9:16 PM CDT	Mesoscale Discussion	SPC	Custer, Fall River, Lawrence, Meade, Oglala Lakota, Pennington	29 min
May 9, 9:34 PM CDT	Severe Thunderstorm Watch	SPC	Corson, Dewey, Stanley	5 hr
May 9, 11:17 PM CDT	Mesoscale Discussion	SPC	Bennett, Butte, Corson, Haakon, Harding, Jackson and 8 more	58 min

Nearby

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