Alert archive / North Dakota / Mesoscale Discussions in 2012

Mesoscale Discussion 876

May 22, 20129 counties in Minnesota; 12 counties in North Dakota; Marshall County, Roberts County, South Dakota

The Storm Prediction Center issued this mesoscale discussion at May 22, 2012, 8:41 PM CDT for 9 counties in Minnesota; 12 counties in North Dakota; Marshall County, Roberts County, South Dakota. It was in force for 64 min.

The area

The outline as issued.

The facts

Issued: May 22, 2012, 8:41 PM CDT (01:41 UTC)
Expired: May 22, 2012, 9:45 PM CDT
In force: 64 min
Issued by: the Storm Prediction Center
Chance of a watch: 40%

All 23 counties

Becker County, MN, Clay County, MN, Mahnomen County, MN, Marshall County, MN, Norman County, MN, Polk County, MN, Red Lake County, MN, Traverse County, MN, Wilkin County, MN, Barnes County, ND, Cass County, ND, Dickey County, ND, Grand Forks County, ND, Griggs County, ND, LaMoure County, ND, Nelson County, ND, Ransom County, ND, Richland County, ND, Sargent County, ND, Steele County, ND, Traill County, ND, Marshall County, SD, Roberts County, SD

The radar

The Fargo/Grand Forks radar (KMVX), 52 km from the middle of the area, began a volume at 01:44 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 nearest sounding before it

Bismarck Municip, ND (KBIS), launched 00:00Z, 1.7 hours before the alert went out and 240 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: 1372 J/kg
Mixed-layer CIN: -73 J/kg
Mixed-layer LCL: 1878 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 68 m²/s²
0-3 km storm-relative helicity: 99 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.6

Open this sounding in Storm Lab

The text

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

717 
ACUS11 KWNS 230141
SWOMCD
SPC MCD 230141 
MNZ000-SDZ000-NDZ000-230245-

MESOSCALE DISCUSSION 0876
NWS STORM PREDICTION CENTER NORMAN OK
0841 PM CDT TUE MAY 22 2012

AREAS AFFECTED...PARTS OF ERN NORTH DAKOTA...NWRN AND W CNTRL
MINNESOTA

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 230141Z - 230245Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...THE SEVERE WEATHER THREAT FOR REMAINING VALID PORTIONS OF
TORNADO WATCH 290 AND SEVERE THUNDERSTORM WATCH 291 CONTINUES.  IT
IS NOT CERTAIN THAT A NEW WW WILL BE NEEDED...BUT TRENDS ARE BEING
MONITORED FOR THE POSSIBILITY OF A NEW WW EAST OF 290/291.

DISCUSSION...RECENT INCREASE IN STORM DEVELOPMENT...SOUTHWEST OF
JAMESTOWN ND INTO THE ABERDEEN SD AREA...APPEARS TO BE WHERE
LOWER/MID TROPOSPHERIC WARM ADVECTION IS BECOMING ENHANCED...NEAR
THE NORTHERN EDGE OF MORE STRONGLY CAPPING ELEVATED MIXED LAYER
AIR...AS THE EXIT REGION OF A STRONG MID/UPPER JET STREAK CONTINUES
TO NOSE EAST NORTHEAST OF THE NORTHERN ROCKIES THIS EVENING.  THIS
FORCING WILL GRADUALLY SPREAD EAST NORTHEASTWARD INTO PARTS OF
NORTHWEST AND WEST CENTRAL MINNESOTA THROUGH 03-05Z.  AS IT
DOES...IT APPEARS THAT IT MAY BEGIN TO OUTRUN A WANING PRE-FRONTAL
LOW-LEVEL INSTABILITY AXIS.  POTENTIAL FOR SIGNIFICANT UPSCALE
CONVECTIVE GROWTH IS BECOMING MORE UNCERTAIN...BUT IT DOES APPEAR
POSSIBLE THAT AT LEAST SCATTERED VIGOROUS CONVECTIVE DEVELOPMENT MAY
BEGIN TO SPREAD TO THE EAST OF CURRENT WATCHES WITHIN THE NEXT HOUR
OR TWO...ACCOMPANIED BY AT LEAST SOME RISK FOR HAIL/LOCALLY STRONG
WIND GUSTS.

..KERR/THOMPSON.. 05/23/2012

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

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

LAT...LON   48199839 48519719 48439623 46889558 45689633 45459694
            45509772 46309880 47269881 47639888 48199839

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 23, 2:04 PM CDT	Mesoscale Discussion	SPC	Aitkin, Becker, Big Stone, Cass, Chippewa, Crow Wing and 14 more	86 min
May 23, 5:27 PM CDT	Mesoscale Discussion	SPC	Anoka, Blue Earth, Carver, Chisago, Dakota, Dodge and 20 more	93 min
May 22, 7:30 PM CDT	Mesoscale Discussion	SPC	Beadle, Brown, Brule, Buffalo, Campbell, Edmunds and 16 more	90 min
May 23, 2:56 PM CDT	Mesoscale Discussion	SPC	Union	94 min
May 23, 4:07 PM CDT	Severe Thunderstorm Watch	SPC	Union	7 hr

Nearby

Mesoscale Discussions in North Dakota, 2012 Mesoscale Discussions in Minnesota, 2012 Mesoscale Discussions in South Dakota, 2012 Every mesoscale discussion in 2012

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.