Alert archive / Minnesota / Mesoscale Discussions in 2012

Mesoscale Discussion 931

May 27, 201239 counties in Minnesota; 5 counties in Wisconsin

The Storm Prediction Center issued this mesoscale discussion at May 27, 2012, 7:47 PM CDT for 39 counties in Minnesota; 5 counties in Wisconsin. It was in force for 88 min.

The area

The outline as issued.

The facts

Issued
May 27, 2012, 7:47 PM CDT (00:47 UTC)
Expired
May 27, 2012, 9:15 PM CDT
In force
88 min
Issued by
the Storm Prediction Center
All 44 counties

Aitkin County, MN, Anoka County, MN, Benton County, MN, Carlton County, MN, Carver County, MN, Chippewa County, MN, Chisago County, MN, Crow Wing County, MN, Dakota County, MN, Dodge County, MN, Douglas County, MN, Goodhue County, MN, Hennepin County, MN, Isanti County, MN, Kanabec County, MN, Kandiyohi County, MN, Le Sueur County, MN, McLeod County, MN, Meeker County, MN, Mille Lacs County, MN, Morrison County, MN, Nicollet County, MN, Pine County, MN, Pope County, MN, Ramsey County, MN, Redwood County, MN, Renville County, MN, Rice County, MN, Scott County, MN, Sherburne County, MN, Sibley County, MN, Stearns County, MN, Steele County, MN, Swift County, MN, Todd County, MN, Wadena County, MN, Waseca County, MN, Washington County, MN, Wright County, MN, Burnett County, WI, Douglas County, WI, Pierce County, WI, Polk County, WI, Saint Croix County, WI

The radar

The Minneapolis radar (KMPX), 99 km from the middle of the area, began a volume at 00:49 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

Minneapolis, MN (KMPX), launched 00:00Z, 0.8 hours before the alert went out and 97 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, Minneapolis, MN at 00:00Z on 2012-05-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1850 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, Minneapolis, MN at 00:00Z on 2012-05-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 79 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
1850 J/kg
Mixed-layer CIN
-25 J/kg
Mixed-layer LCL
1669 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
79 m²/s²
0-3 km storm-relative helicity
285 m²/s²
Significant tornado parameter
0.7
Supercell composite
17.0

Open this sounding in Storm Lab

The text

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

786 
ACUS11 KWNS 280048
SWOMCD
SPC MCD 280047
WIZ000-MNZ000-280215-

MESOSCALE DISCUSSION 0931
NWS STORM PREDICTION CENTER NORMAN OK
0747 PM CDT SUN MAY 27 2012

AREAS AFFECTED...MN...NWRN WI

CONCERNING...SEVERE THUNDERSTORM WATCH 307...

VALID 280047Z - 280215Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 307
CONTINUES.

SUMMARY...THUNDERSTORMS ACROSS MN WILL CONTINUE TO POSE A THREAT FOR
HAIL AND DAMAGING WIND DURING THE NEXT FEW HOURS. ADDITIONALLY...A
LOW TORNADO THREAT EXISTS...PRIMARILY ACROSS ERN PORTIONS OF THE
WATCH. HEAVY RAIN IS ALSO POSSIBLE AS STORMS TRAIN NWD.

DISCUSSION...THUNDERSTORMS ARE EXPECTED TO CONTINUE IN THE WARM
SECTOR AHEAD OF A SLOW-MOVING COLD FRONT. 00Z SFC ANALYSIS PLACED
THE COLD FRONT ALONG A NE TO SW ORIENTED LINE FROM AXN TO PQN WITH A
WARM FRONT EXTENDING EWD FROM PKD TO CDD. THE AIR MASS IN THE WARM
SECTION IS CHARACTERIZED BY TEMPERATURES IN THE MID 80S AND
DEWPOINTS IN THE UPPER 60S TO LOW 70S. 00Z MESOANALYSIS DEPICTS AN
INSTABILITY AXIS WITH MLCAPE VALUES AROUND 1500 J/KG EXISTS JUST S
OF THE WARM FRONT ACROSS W-CNTRL MN AND NWRN WI. PRIMARY THREAT
ACROSS MOST OF THE AREA APPEARS TO BE SEVERE HAIL/WIND. WIND THREAT
MAY INCREASE DURING THE NEXT FEW HOURS AS UPSCALE GROWTH INTO A
CONVECTIVE LINE/MCS IS POSSIBLE. LOW TORNADO THREAT EXISTS ACROSS
WRN MN/NWRN WI AS SLIGHTLY BACKED FLOW ENHANCES LOW-LEVEL
CONVERGENCE AND SHEAR.

..MOSIER.. 05/28/2012

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

ATTN...WFO...DLH...ARX...MPX...FGF...FSD...

LAT...LON   44559584 45559577 46729533 46879392 46539154 43759277
            44559584

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 27, 9:51 PM CDTMesoscale DiscussionSPCBlue Earth, Jackson, Martin, Nicollet, Watonwan84 min
May 27, 10:11 PM CDTMesoscale DiscussionSPCAitkin, Anoka, Benton, Blue Earth, Brown, Carlton and 45 more94 min
May 28, 1:48 PM CDTMesoscale DiscussionSPCAnoka, Benton, Carlton, Carver, Chisago, Dakota and 17 more57 min
May 28, 2:07 PM CDTSevere Thunderstorm WatchSPCAnoka, Benton, Carlton, Carver, Chisago, Dakota and 14 more6 hr
May 28, 3:58 PM CDTMesoscale DiscussionSPCAnoka, Benton, Carlton, Carver, Chisago, Dakota and 16 more92 min
May 28, 12:00 PM CDTMesoscale DiscussionSPCAdams, Brown, Calumet, Clark, Columbia, Crawford and 34 more60 min
May 28, 12:54 PM CDTSevere Thunderstorm WatchSPCAdams, Brown, Calumet, Clark, Columbia, Crawford and 47 more7 hr
May 28, 6:28 PM CDTMesoscale DiscussionSPCBarron, Chippewa, Dunn, Rusk, Sawyer, Washburn62 min

Nearby

Mesoscale Discussions in Minnesota, 2012Mesoscale Discussions in Wisconsin, 2012Every 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.