Alert archive / Minnesota / Mesoscale Discussions in 2012

Mesoscale Discussion 1420

July 6, 201238 counties in Minnesota; 10 counties in South Dakota; 9 counties in Wisconsin

The Storm Prediction Center issued this mesoscale discussion at Jul 6, 2012, 6:02 PM CDT for 38 counties in Minnesota; 10 counties in South Dakota; 9 counties in Wisconsin. It was in force for 28 min.

The area

The outline as issued.

The facts

Issued
Jul 6, 2012, 6:02 PM CDT (23:02 UTC)
Expired
Jul 6, 2012, 6:30 PM CDT
In force
28 min
Issued by
the Storm Prediction Center
Chance of a watch
60%
All 57 counties

Anoka County, MN, Benton County, MN, Brown County, MN, Carlton County, MN, Carver County, MN, Chippewa County, MN, Chisago County, MN, Douglas County, MN, Hennepin County, MN, Isanti County, MN, Kanabec County, MN, Kandiyohi County, MN, Lac qui Parle County, MN, Lincoln County, MN, Lyon County, MN, McLeod County, MN, Meeker County, MN, Mille Lacs County, MN, Morrison County, MN, Murray County, MN, Nicollet County, MN, Pine County, MN, Pipestone County, MN, Pope County, MN, Ramsey County, MN, Redwood County, MN, Renville County, MN, Rock County, MN, Scott County, MN, Sherburne County, MN, Sibley County, MN, Stearns County, MN, Stevens County, MN, Swift County, MN, Todd County, MN, Washington County, MN, Wright County, MN, Yellow Medicine County, MN, Bon Homme County, SD, Brookings County, SD, Hanson County, SD, Hutchinson County, SD, Lake County, SD, McCook County, SD, Minnehaha County, SD, Moody County, SD, Turner County, SD, Yankton County, SD, Barron County, WI, Bayfield County, WI, Burnett County, WI, Douglas County, WI, Polk County, WI, Rusk County, WI, Saint Croix County, WI, Sawyer County, WI, Washburn County, WI

The radar

The Minneapolis radar (KMPX), 64 km from the middle of the area, began a volume at 23:06 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

Minneapolis, MN (KMPX), launched 12:00Z, 11.0 hours before the alert went out and 61 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 12:00Z on 2012-07-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2912 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 12:00Z on 2012-07-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 120 square meters per square second.1939Sfc1 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
2912 J/kg
Mixed-layer CIN
-98 J/kg
Mixed-layer LCL
925 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
120 m²/s²
0-3 km storm-relative helicity
137 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.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 6, 6:39 PM CDTSevere Thunderstorm WatchSPCAnoka, Blue Earth, Brown, Carver, Chisago, Dakota and 22 more7 hr
Jul 5, 9:52 PM CDTMesoscale DiscussionSPCButte, Custer, Fall River, Harding, Lawrence, Meade and 2 more53 min

Nearby

Mesoscale Discussions in Minnesota, 2012Mesoscale Discussions in South Dakota, 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.