Alert archive / Minnesota / Severe Thunderstorm Watches in 2011

Severe Thunderstorm Watch 714

August 1, 201117 counties in Minnesota; Burnett County, Douglas County, Washburn County, Wisconsin

The Storm Prediction Center issued this severe thunderstorm watch at Aug 1, 2011, 10:35 PM CDT for 17 counties in Minnesota; Burnett County, Douglas County, Washburn County, Wisconsin. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Aug 1, 2011, 10:35 PM CDT (03:35 UTC)
Expired
Aug 2, 2011, 6:00 AM CDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
60 kt

Counties Aitkin County, MN, Becker County, MN, Carlton County, MN, Cass County, MN, Clay County, MN, Crow Wing County, MN, Douglas County, MN, Grant County, MN, Hubbard County, MN, Kanabec County, MN, Mille Lacs County, MN, Morrison County, MN, Otter Tail County, MN, Pine County, MN, Todd County, MN, Wadena County, MN, Wilkin County, MN, Burnett County, WI, Douglas County, WI, Washburn County, WI

The radar

The Duluth radar (KDLH), 131 km from the middle of the area, began a volume at 03:38 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.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
10%
One or more EF2 to EF5 tornadoes
5%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
20%
One or more hailstones of 2 inches or more
10%
Six or more combined severe hail and wind reports
60%

Warnings issued inside it

5 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Aug 1, 10:59 PM CDTFlash Flood WarningDLHAitkin, Cass, Crow Wing, Itasca6 hr
Aug 1, 11:26 PM CDTSevere Thunderstorm WarningFGFBecker, Hubbard, Otter Tail, Wadena64 min
Aug 2, 12:40 AM CDTFlash Flood WarningDLHCarlton, Saint Louis4 hr
Aug 2, 1:43 AM CDTSevere Thunderstorm WarningDLHDouglas30 min
Aug 2, 2:38 AM CDTSevere Thunderstorm WarningDLHBayfield, Burnett, Douglas, Sawyer, Washburn67 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 3.6 hours before the alert went out and 200 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 2011-08-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3 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 2011-08-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 308 square meters per square second.193958Sfc1 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
3 J/kg
Mixed-layer CIN
-595 J/kg
Mixed-layer LCL
1515 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
308 m²/s²
0-3 km storm-relative helicity
808 m²/s²
Significant tornado parameter
0.0
Supercell composite
9.9

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 1, 9:40 PM CDTMesoscale DiscussionSPCAitkin, Anoka, Becker, Benton, Big Stone, Carlton and 29 more95 min
Aug 2, 1:24 AM CDTMesoscale DiscussionSPCAitkin, Anoka, Benton, Carlton, Chisago, Crow Wing and 5 more96 min
Aug 2, 3:32 AM CDTMesoscale DiscussionSPCAitkin, Anoka, Benton, Carlton, Chisago, Crow Wing and 5 more88 min
Aug 2, 5:23 AM CDTSevere Thunderstorm WatchSPCAnoka, Benton, Big Stone, Carver, Chippewa, Chisago and 25 more7 hr
Aug 2, 9:02 AM CDTMesoscale DiscussionSPCChisago, Ramsey, Washington58 min
Aug 2, 12:57 PM CDTMesoscale DiscussionSPCHouston93 min
Aug 2, 2:20 AM CDTSevere Thunderstorm WatchSPCAshland, Barron, Bayfield, Burnett, Chippewa, Clark and 24 more10 hr
Aug 2, 6:19 AM CDTMesoscale DiscussionSPCAdams, Brown, Calumet, Chippewa, Clark, Columbia and 32 more86 min
Aug 2, 11:51 AM CDTMesoscale DiscussionSPCAshland, Barron, Bayfield, Burnett, Chippewa, Douglas and 11 more24 min
Aug 2, 5:22 PM CDTSevere Thunderstorm WatchSPCKenosha, Milwaukee, Racine, Rock, Walworth, Waukesha9 hr

Nearby

Severe Thunderstorm Watches in Minnesota, 2011Severe Thunderstorm Watches in Wisconsin, 2011Every severe thunderstorm watch 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.