Alert archive / Minnesota / Severe Thunderstorm Watches in 2011

Severe Thunderstorm Watch 647

July 15, 201120 counties in Minnesota

The Storm Prediction Center issued this severe thunderstorm watch at Jul 15, 2011, 6:40 AM CDT for 20 counties in Minnesota. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Jul 15, 2011, 6:40 AM CDT (11:40 UTC)
Expired
Jul 15, 2011, 1:00 PM CDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt

Counties Anoka County, MN, Benton County, MN, Carver County, MN, Chisago County, MN, Douglas County, MN, Hennepin County, MN, Isanti County, MN, Kanabec County, MN, Kandiyohi County, MN, McLeod County, MN, Meeker County, MN, Mille Lacs County, MN, Morrison County, MN, Pope County, MN, Ramsey County, MN, Sherburne County, MN, Stearns County, MN, Todd County, MN, Washington County, MN, Wright County, MN

The radar

The Minneapolis radar (KMPX), 111 km from the middle of the area, began a volume at 11:40 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
20%
One or more EF2 to EF5 tornadoes
5%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
30%
Six or more combined severe hail and wind reports
70%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jul 15, 6:44 AM CDTSevere Thunderstorm WarningMPXStearns, Todd61 min
Jul 15, 6:50 AM CDTSevere Thunderstorm WarningMPXDouglas55 min
Jul 15, 7:05 AM CDTSevere Thunderstorm WarningMPXStearns55 min
Jul 15, 7:33 AM CDTSevere Thunderstorm WarningMPXDouglas, Pope, Stearns, Todd57 min
Jul 15, 8:14 AM CDTFlash Flood WarningMPXDouglas, Todd3 hr
Jul 15, 8:51 AM CDTFlash Flood WarningMPXPope, Stearns3 hr
Jul 15, 9:00 AM CDTSevere Thunderstorm WarningMPXMeeker, Stearns, Wright45 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, 11.7 hours before the alert went out and 109 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 2011-07-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2011-07-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 78 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
703 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
78 m²/s²
0-3 km storm-relative helicity
271 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.2

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 15, 2:56 AM CDTSevere Thunderstorm WatchSPCBecker, Beltrami, Clay, Clearwater, Hubbard, Mahnomen and 8 more7 hr
Jul 15, 6:30 AM CDTMesoscale DiscussionSPCBenton, Carver, Clay, Douglas, Grant, Hennepin and 14 more2 hr
Jul 15, 11:20 AM CDTMesoscale DiscussionSPCAnoka, Blue Earth, Brown, Carver, Chippewa, Dakota and 30 more85 min
Jul 15, 2:21 PM CDTMesoscale DiscussionSPCBlue Earth, Dodge, Faribault, Fillmore, Freeborn, Houston and 6 more114 min
Jul 15, 6:10 PM CDTMesoscale DiscussionSPCBecker, Beltrami, Clay, Clearwater, Grant, Hubbard and 8 more65 min

Nearby

Severe Thunderstorm Watches in Minnesota, 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.