Alert archive / Minnesota / Tornado Watches in 2010

Tornado Watch 542

July 27, 201044 counties in Minnesota; 18 counties in Wisconsin

The Storm Prediction Center issued this tornado watch at Jul 27, 2010, 3:29 PM CDT for 44 counties in Minnesota; 18 counties in Wisconsin. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued: Jul 27, 2010, 3:29 PM CDT (20:29 UTC)
Expired: Jul 27, 2010, 10:16 PM CDT
In force: 7 hr
Issued by: the Storm Prediction Center
Largest hail expected: 2.5 in
Strongest gust expected: 70 kt

All 62 counties

Aitkin County, MN, Anoka County, MN, Benton County, MN, Brown County, MN, Carlton County, MN, Carver County, MN, Cass County, MN, Chippewa County, MN, Chisago County, MN, Crow Wing County, MN, Dakota County, MN, Douglas County, MN, Goodhue County, MN, Grant County, MN, Hennepin County, MN, Isanti County, MN, Kanabec County, MN, Kandiyohi County, MN, Lac qui Parle County, MN, Le Sueur County, MN, McLeod County, MN, Meeker County, MN, Mille Lacs County, MN, Morrison County, MN, Nicollet County, MN, Otter Tail 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, Stevens County, MN, Swift County, MN, Todd County, MN, Wadena County, MN, Washington County, MN, Wilkin County, MN, Wright County, MN, Yellow Medicine County, MN, Ashland County, WI, Barron County, WI, Bayfield County, WI, Burnett County, WI, Chippewa County, WI, Douglas County, WI, Dunn County, WI, Eau Claire County, WI, Iron County, WI, Pepin County, WI, Pierce County, WI, Polk County, WI, Price County, WI, Rusk County, WI, Saint Croix County, WI, Sawyer County, WI, Taylor County, WI, Washburn County, WI

The radar

The Minneapolis radar (KMPX), 121 km from the middle of the area, began a volume at 20:31 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: 70%
One or more EF2 to EF5 tornadoes: 30%
Ten or more severe wind reports: 80%
One or more gusts of 65 knots or more: 40%
Ten or more severe hail reports: 70%
One or more hailstones of 2 inches or more: 30%
Six or more combined severe hail and wind reports: 95%

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
Jul 27, 4:02 PM CDT	Tornado Warning	FGF	Grant, Otter Tail	48 min
Jul 27, 4:19 PM CDT	Tornado Warning	MPX	Douglas, Pope, Stevens	41 min
Jul 27, 4:21 PM CDT	Severe Thunderstorm Warning	DLH	Aitkin	39 min
Jul 27, 4:28 PM CDT	Severe Thunderstorm Warning	MPX	Douglas	36 min
Jul 27, 4:36 PM CDT	Severe Thunderstorm Warning	MPX	Todd	39 min
Jul 27, 4:42 PM CDT	Tornado Warning	MPX	Morrison	33 min
Jul 27, 4:45 PM CDT	Tornado Warning	MPX	Morrison, Todd	45 min
Jul 27, 4:53 PM CDT	Severe Thunderstorm Warning	DLH	Bayfield, Douglas	52 min
Jul 27, 5:08 PM CDT	Severe Thunderstorm Warning	DLH	Douglas	22 min
Jul 27, 5:14 PM CDT	Tornado Warning	MPX	Benton, Morrison, Stearns	46 min
Jul 27, 5:16 PM CDT	Tornado Warning	MPX	Douglas, Morrison, Stearns, Todd	44 min
Jul 27, 5:40 PM CDT	Severe Thunderstorm Warning	MPX	Benton, Stearns	35 min
Jul 27, 5:42 PM CDT	Severe Thunderstorm Warning	DLH	Ashland, Bayfield, Iron, Sawyer	63 min
Jul 27, 5:45 PM CDT	Severe Thunderstorm Warning	MPX	Benton, Kanabec, Mille Lacs, Morrison	45 min
Jul 27, 5:46 PM CDT	Severe Thunderstorm Warning	MPX	Kandiyohi, Meeker	59 min
Jul 27, 5:49 PM CDT	Tornado Warning	DLH	Ashland, Bayfield, Iron	41 min
Jul 27, 5:52 PM CDT	Severe Thunderstorm Warning	DLH	Pine	23 min
Jul 27, 6:00 PM CDT	Severe Thunderstorm Warning	MPX	Benton, Mille Lacs, Sherburne, Stearns	45 min
Jul 27, 6:09 PM CDT	Severe Thunderstorm Warning	DLH	Pine	36 min
Jul 27, 6:15 PM CDT	Severe Thunderstorm Warning	MPX	Chippewa, Redwood, Renville, Yellow Medicine	60 min
Jul 27, 6:17 PM CDT	Severe Thunderstorm Warning	MPX	Chisago, Isanti, Kanabec, Mille Lacs	43 min
Jul 27, 6:24 PM CDT	Severe Thunderstorm Warning	MPX	Anoka, Isanti, Meeker, Sherburne, Stearns, Wright	51 min
Jul 27, 6:28 PM CDT	Tornado Warning	DLH	Ashland, Iron	47 min
Jul 27, 6:34 PM CDT	Severe Thunderstorm Warning	DLH	Pine	26 min
Jul 27, 6:45 PM CDT	Severe Thunderstorm Warning	DLH	Burnett, Sawyer, Washburn	45 min
Jul 27, 6:46 PM CDT	Severe Thunderstorm Warning	MPX	Kandiyohi, McLeod, Meeker, Renville, Wright	44 min
Jul 27, 7:13 PM CDT	Tornado Warning	DLH	Iron	16 min
Jul 27, 7:14 PM CDT	Tornado Warning	DLH	Ashland, Iron, Price	39 min
Jul 27, 7:31 PM CDT	Severe Thunderstorm Warning	MPX	Barron, Chippewa, Dunn, Polk, Rusk, Saint Croix	44 min
Jul 27, 7:39 PM CDT	Severe Thunderstorm Warning	DLH	Price, Sawyer, Washburn	66 min
Jul 27, 8:10 PM CDT	Severe Thunderstorm Warning	MPX	Barron, Chippewa, Dunn, Rusk, Saint Croix	50 min
Jul 27, 8:40 PM CDT	Severe Thunderstorm Warning	ARX	Clark, Taylor	65 min
Jul 27, 8:44 PM CDT	Severe Thunderstorm Warning	DLH	Price	31 min
Jul 27, 9:07 PM CDT	Severe Thunderstorm Warning	MPX	Chippewa, Dunn, Eau Claire, Pepin, Pierce	38 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 12:00Z, 8.5 hours before the alert went out and 120 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: 2143 J/kg
Mixed-layer CIN: -90 J/kg
Mixed-layer LCL: 832 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 220 m²/s²
0-3 km storm-relative helicity: 256 m²/s²
Significant tornado parameter: 1.9
Supercell composite: 21.5

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 26, 9:00 PM CDT	Mesoscale Discussion	SPC	Beltrami, Kittson, Lake of the Woods, Marshall, Pennington, Polk and 2 more	90 min
Jul 26, 10:12 PM CDT	Severe Thunderstorm Watch	SPC	Beltrami, Clay, Clearwater, Kittson, Koochiching, Lake of the Woods and 7 more	7 hr
Jul 27, 1:05 AM CDT	Mesoscale Discussion	SPC	Becker, Clay, Hubbard, Mahnomen, Norman, Otter Tail and 2 more	55 min
Jul 27, 1:24 AM CDT	Severe Thunderstorm Watch	SPC	Aitkin, Becker, Beltrami, Benton, Cass, Clay and 16 more	8 hr
Jul 27, 3:50 AM CDT	Mesoscale Discussion	SPC	Becker, Clay, Hubbard, Mahnomen, Norman, Otter Tail and 2 more	85 min
Jul 27, 7:01 AM CDT	Mesoscale Discussion	SPC	Aitkin, Becker, Benton, Carlton, Cass, Chisago and 15 more	89 min
Jul 27, 1:43 PM CDT	Mesoscale Discussion	SPC	Anoka, Benton, Big Stone, Chisago, Douglas, Grant and 18 more	32 min
Jul 27, 3:09 PM CDT	Severe Thunderstorm Watch	SPC	Big Stone, Lincoln, Lyon, Murray, Pipestone, Rock and 1 more	6 hr
Jul 27, 10:44 AM CDT	Mesoscale Discussion	SPC	Brown, Forest, Langlade, Lincoln, Marathon, Marinette and 8 more	61 min
Jul 27, 5:23 PM CDT	Mesoscale Discussion	SPC	Florence, Forest, Marinette, Oneida, Vilas	67 min
Jul 27, 6:01 PM CDT	Tornado Watch	SPC	Florence, Forest, Langlade, Lincoln, Marathon, Marinette and 5 more	6 hr

Nearby

Tornado Watches in Minnesota, 2010 Tornado Watches in Wisconsin, 2010 Every tornado watch in 2010

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.