July 1-2, 2011 Preliminary Severe Weather Summary

Radar Imagery Damage Photos Damage Reports Rainfall Totals

Discussion about the event

During the early evening of July 1 around 7 pm, a line of showers and thunderstorms developed on a cold front over south central Minnesota and north central Iowa. Shortly thereafter, the storms over south central Minnesota began racing east ahead of the front, into the hot and humid airmass that was over the Upper Mississippi River Valley region.  The result from this was numerous reports of severe wind gusts as well as wind damage across much of southeast Minnesota into southwest into central Wisconsin. A few reports of wind damage were also received in northeast Iowa.  What was most interesting about this severe weather event was that even though the storms were weakening as they tracked east through the region, they still produced plenty of severe weather.  The cause of the weakening was a combination of temperatures cooling through the evening and the environment turning less favorable for storms to organize over Wisconsin.  Nevertheless, severe wind gusts and wind damage occurred into areas as far east as Sparta, Tomah, Necedah and Big Flats in the Upper Mississippi River Valley region.

Radar Imagery

Below are time radar time lapses of reflectivity (left) and velocity (right) along with the severe thunderstorm warnings (yellow boxes) from 721pm through 1225 am.  Caution!  These are large files and may take a while to download (~16MB). 

Radar reflectivity loop from 721 pm through 122 5am

KARX Reflectivity & Warnings(721pm-1225am)

Radar velocity time lapse from 721 pm through 1225 am

KARX Velocity & Warnings (721pm-1225am)

Damage photos

The following photos are courtesy of Mike McCaffrey, taken in Onalaska, WI

damage damage damage
damage damage damage

Storm Report Summary

The image below displays the warnings and severe weather reports that were received from the afternoon of July 1 into the early morning hours of July 2.

July 1-2, 2011 Servere Weather Reports & Warnings

The following is a summary of reports received into the National Weather Service in La Crosse as of 1046 am July 2nd:/p>

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0847 PM     TSTM WND GST     HAYFIELD                43.89N 92.85W
07/01/2011  E50.00 MPH       DODGE              MN   FIRE DEPT/RESCUE

0902 PM     TSTM WND GST     HAYFIELD                43.89N 92.85W
07/01/2011  E60.00 MPH       DODGE              MN   AMATEUR RADIO

0909 PM     TSTM WND GST     5 S ROCHESTER           43.94N 92.48W
07/01/2011  M58.00 MPH       OLMSTED            MN   ASOS

0910 PM     TSTM WND GST     3 SW PLAINVIEW          44.13N 92.21W
07/01/2011  M66.00 MPH       WABASHA            MN   AMATEUR RADIO

0916 PM     TSTM WND GST     ELGIN                   44.13N 92.25W
07/01/2011  M60.00 MPH       WABASHA            MN   AMATEUR RADIO

0930 PM     TSTM WND DMG     AUSTIN                  43.67N 92.97W
07/01/2011                   MOWER              MN   BROADCAST MEDIA

            A COUPLE OF 6-8 INCH IN DIAMETER TREES DOWN ON SOUTHEAST
            SIDE OF TOWN.

0942 PM     TSTM WND DMG     LEWISTON                43.98N 91.87W
07/01/2011                   WINONA             MN   LAW ENFORCEMENT

            TREE BLOWN DOWN

0942 PM     TSTM WND GST     2 W SPRING VALLEY       43.69N 92.43W
07/01/2011  M55.00 MPH       FILLMORE           MN   TRAINED SPOTTER

0945 PM     TSTM WND GST     6 W STEWARTVILLE        43.86N 92.61W
07/01/2011  E50.00 MPH       OLMSTED            MN   PUBLIC

0952 PM     TSTM WND DMG     NW WYKOFF               43.71N 92.27W
07/01/2011                   FILLMORE           MN   LAW ENFORCEMENT

            LAW ENFORCEMENT REPORTED ROOF DAMAGE TO THE WYKOFF MIDDLE
            SCHOOL

0956 PM     TSTM WND GST     2 SE EYOTA              43.97N 92.20W
07/01/2011  M63.00 MPH       OLMSTED            MN   MESONET

0958 PM     TSTM WND GST     5 W PRESTON             43.67N 92.18W
07/01/2011  M72.00 MPH       FILLMORE           MN   AWOS

1002 PM     TSTM WND DMG     OSSEO                   44.58N 91.22W
07/01/2011                   TREMPEALEAU        WI   LAW ENFORCEMENT

            POWER LINES DOWN

1006 PM     TSTM WND DMG     2 S LYLE                43.48N 92.94W
07/01/2011                   MITCHELL           IA   LAW ENFORCEMENT

            LARGE TREE DOWN

1006 PM     TSTM WND DMG     2 W ST. ANSGAR          43.38N 92.96W
07/01/2011                   MITCHELL           IA   LAW ENFORCEMENT

            LARGE TREE DOWN

1006 PM     HAIL             4 W OSAGE               43.28N 92.89W
07/01/2011  E0.50 INCH       MITCHELL           IA   LAW ENFORCEMENT

1014 PM     TSTM WND GST     GALESVILLE              44.08N 91.36W
07/01/2011  E50.00 MPH       TREMPEALEAU        WI   NWS EMPLOYEE

1015 PM     TSTM WND GST     4 NW HOKAH              43.80N 91.41W
07/01/2011  M61.00 MPH       HOUSTON            MN   CO-OP OBSERVER

1017 PM     TSTM WND DMG     OSAGE                   43.28N 92.81W
07/01/2011                   MITCHELL           IA   LAW ENFORCEMENT

            A FEW TREES BLOWN DOWN

1020 PM     TSTM WND DMG     ALMA CENTER             44.44N 90.91W
07/01/2011                   JACKSON            WI   LAW ENFORCEMENT

            TREES AND POWER LINES DOWN.

1022 PM     TSTM WND GST     GRAND MEADOW            43.71N 92.57W
07/01/2011  E75.00 MPH       MOWER              MN   BROADCAST MEDIA

1022 PM     TSTM WND DMG     DAKOTA                  43.91N 91.36W
07/01/2011                   WINONA             MN   LAW ENFORCEMENT

            TREE BLOWN DOWN

1022 PM     TSTM WND DMG     HOKAH                   43.76N 91.35W
07/01/2011                   HOUSTON            MN   EMERGENCY MNGR

            TREES DOWN IN TOWN

1027 PM     TSTM WND DMG     LA CRESCENT             43.83N 91.30W
07/01/2011                   HOUSTON            MN   EMERGENCY MNGR

            TREES AND POWER LINES DOWN.

1030 PM     TSTM WND DMG     3 N LA CROSSE           43.87N 91.23W
07/01/2011                   LA CROSSE          WI   PUBLIC

            NUMEROUS TREES SNAPPED OFF AND UPROOTED ALONG THE
            SHORELINE OF LAKE ONALASKA. ESTIMATED WIND GUSTS OF 70
            MPH.

1030 PM     TSTM WND DMG     LA CROSSE               43.83N 91.23W
07/01/2011                   LA CROSSE          WI   LAW ENFORCEMENT

            TREE DOWN IN COPELAND PARK

1030 PM     TSTM WND DMG     ONALASKA                43.89N 91.22W
07/01/2011                   LA CROSSE          WI   PUBLIC

            A COUPLE OF TREES AND SEVERAL LIMBS DOWN ON THE NORTHWEST
            SIDE OF TOWN.

1030 PM     TSTM WND DMG     ONALASKA                43.89N 91.22W
07/01/2011                   LA CROSSE          WI   TRAINED SPOTTER

            8-10 TREES UPROOTED ALONG WELL ST...BETWEEN OAK AVE AND
            11TH AVE. A COUPLE TREES ALSO HAD THEIR TOPS SNAPPED OFF.

1031 PM     TSTM WND GST     1 E LA CROSSE           43.83N 91.21W
07/01/2011  E49.00 MPH       LA CROSSE          WI   MESONET

1033 PM     TSTM WND GST     2 S LA CROSSE           43.80N 91.23W
07/01/2011  M56.00 MPH       LA CROSSE          WI   AMATEUR RADIO

            SOME BRANCHES BLOWN OFF TREES.

1033 PM     TSTM WND GST     ONALASKA                43.89N 91.22W
07/01/2011  E60.00 MPH       LA CROSSE          WI   TRAINED SPOTTER

1042 PM     NON-TSTM WND GST 5 NNE STODDARD          43.73N 91.18W
07/01/2011  E50.00 MPH       LA CROSSE          WI   NWS EMPLOYEE

1045 PM     TSTM WND DMG     3 W NEILLSVILLE         44.56N 90.65W
07/01/2011                   CLARK              WI   EMERGENCY MNGR

            TREE BLOWN DOWN ON VEHICLE.

1050 PM     HAIL             NORA SPRINGS            43.14N 93.01W
07/01/2011  E0.50 INCH       FLOYD              IA   LAW ENFORCEMENT

1051 PM     TSTM WND DMG     2 SE VEEFKIND           44.67N 90.36W
07/01/2011                   CLARK              WI   TRAINED SPOTTER

            TRAINED SPOTTER REPORTED A TREE DOWN

1051 PM     TSTM WND DMG     9 SSE RIPLINGER         44.71N 90.33W
07/01/2011                   CLARK              WI   TRAINED SPOTTER

            TRAINED SPOTTER REPORTED METAL SHED SIDING AND ROOF
            DAMAGE

1055 PM     TSTM WND GST     2 E LOYAL               44.74N 90.46W
07/01/2011  E55.00 MPH       CLARK              WI   TRAINED SPOTTER

1055 PM     TSTM WND DMG     SPARTA                  43.94N 90.81W
07/01/2011                   MONROE             WI   EMERGENCY MNGR

            NUMEROUS TREE LIMBS DOWN AROUND TOWN AND ALSO SOME ROOF
            DAMAGE TO A FEW BUILDINGS.

1059 PM     TSTM WND DMG     SPARTA                  43.94N 90.81W
07/01/2011                   MONROE             WI   AMATEUR RADIO

            LARGE TREE BLOWN DOWN AND SOME ROOF DAMAGE TO BUILDING ON
            WATER STREET.

1136 PM     LIGHTNING        WINONA                  44.05N 91.66W
07/01/2011                   WINONA             MN   LAW ENFORCEMENT

            HOUSE STRUCK BY LIGHTNING

1140 PM     TSTM WND DMG     FINLEY                  44.22N 90.13W
07/01/2011                   JUNEAU             WI   BROADCAST MEDIA

            TREES DOWN ALONG HWY 80 AND COUNTY ROAD F

1142 PM     TSTM WND GST     5 E NECEDAH             44.02N 89.97W
07/01/2011  M63.00 MPH       ADAMS              WI   TRAINED SPOTTER

1145 PM     TSTM WND DMG     1 N NECEDAH             44.04N 90.07W
07/01/2011                   JUNEAU             WI   LAW ENFORCEMENT

            SEVERAL TREES DOWN ACROSS HIGHWAY 21 NORTH OF NECEDAH.

1152 PM     TSTM WND GST     BIG FLATS               44.12N 89.80W
07/01/2011  E60.00 MPH       ADAMS              WI   PUBLIC

Rainfall Totals

The following is a listing of rainfall reports received into the National Weather Service in La Crosse between 7 am July 1st and 7 am July 2nd:

LOCATION                   RAINFALL    TIME     LAT/LON


NORTHEAST IOWA

...ALLAMAKEE COUNTY...
DORCHESTER HIGHWAY 76      0.13        0700 AM  43.42N 91.51W
ION                        0.02        0700 AM  43.11N 91.27W
HARPERS FERRY              0.01        0700 AM  43.17N 91.24W

...CHICKASAW COUNTY...
IONIA                      0.11        0700 AM  43.03N 92.50W

...CLAYTON COUNTY...
MARQUETTE                  0.08        0700 AM  43.04N 91.21W

...FAYETTE COUNTY...
FAYETTE                    0.04        0700 AM  42.85N 91.82W
OELWEIN AWOS               0.01        0700 AM  42.68N 91.97W
ELDORADO                   0.01        0700 AM  43.05N 91.81W

...FLOYD COUNTY...
COLWELL                    0.21        0700 AM  43.16N 92.59W
CHARLES CITY COOP          0.15        0700 AM  43.08N 92.67W
CHARLES CITY CEDAR RVR     0.11        0700 AM  43.06N 92.67W
NASHUA                     0.02        0700 AM  42.94N 92.57W
CHARLES CITY AWOS          0.01        0700 AM  43.07N 92.61W

...HOWARD COUNTY...
CRESCO                     0.52        0700 AM  43.37N 92.11W

...MITCHELL COUNTY...
OSAGE                      0.78        0700 AM  43.28N 92.81W
ST ANSGAR                  0.39        0700 AM  43.37N 92.83W

...WINNESHIEK COUNTY...
DECORAH                    0.29        0700 AM  43.30N 91.80W
DECORAH AWOS               0.13        0700 AM  43.28N 91.74W
BLUFFTON                   0.13        0700 AM  43.41N 91.90W

SOUTHEAST MINNESOTA

...DODGE COUNTY...
DODGE CENTER AWOS          0.50        0700 AM  44.03N 92.83W

...FILLMORE COUNTY...
CARIMONA                   0.35        0700 AM  43.66N 92.15W
SPRING VALLEY 3E           0.31        0700 AM  43.68N 92.33W
PRESTON AWOS               0.27        0700 AM  43.68N 92.18W
PILOT MOUND                0.26        0700 AM  43.78N 92.03W
LANESBORO                  0.13        0700 AM  43.72N 91.97W
PRESTON                    0.11        0700 AM  43.67N 92.07W

...HOUSTON COUNTY...
HOUSTON                    0.06        0700 AM  43.77N 91.57W
MOUND PRAIRIE              0.04        0700 AM  43.78N 91.45W

...MOWER COUNTY...
AUSTIN AWOS                1.01        0700 AM  43.67N 92.93W
AUSTIN                     0.93        0700 AM  43.67N 92.95W
GRAND MEADOW               0.79        0700 AM  43.71N 92.56W
AUSTIN 3S                  0.77        0700 AM  43.62N 93.00W
LANSING                    0.57        0700 AM  43.75N 92.95W

...OLMSTED COUNTY...
POST TOWN                  0.61        0700 AM  44.09N 92.82W
ROCHESTER - CASCADE CREEK  0.49        0700 AM  44.03N 92.48W
ROCHESTER BELTLINE         0.49        0700 AM  43.91N 92.50W
ROCHESTER - SILVER CREEK   0.48        0700 AM  44.03N 92.42W
ROCHESTER - BEAR CREEK     0.37        0700 AM  43.92N 92.48W
ROCHESTER ASOS             0.31        0700 AM
ELBA                       0.02        0700 AM  44.05N 92.05W

...WABASHA COUNTY...
WABASHA                    0.35        0700 AM  44.39N 92.05W
THEILMAN                   0.32        0700 AM  44.28N 92.19W
LAKE CITY COOP             0.28        0700 AM  44.43N 92.28W
KELLOGG                    0.23        0700 AM  44.32N 92.00W
LAKE CITY                  0.05        0700 AM  44.45N 92.26W

...WINONA COUNTY...
MINNESOTA CITY             0.31        0700 AM  44.16N 91.81W
WINONA                     0.30        0700 AM  44.09N 91.67W
ALTURA 5W                  0.27        0700 AM  44.06N 92.04W
ALTURA                     0.26        0700 AM  44.15N 92.01W
DAKOTA                     0.08        0700 AM  43.92N 91.37W
LA CRESCENT DAM 7          0.05        0700 AM  43.87N 91.31W

SOUTHWEST AND CENTRAL WISCONSIN

...BUFFALO COUNTY...
MONDOVI 6S                 0.37        0700 AM  44.48N 91.67W
ALMA DAM 4                 0.36        0700 AM  44.33N 91.92W

...CLARK COUNTY...
OWEN                       0.10        0700 AM  44.98N 90.55W
NEILLSVILLE 4 NNE          0.05        0700 AM  44.61N 90.56W
NEILLSVILLE                0.04        0700 AM  44.56N 90.61W

...CRAWFORD COUNTY...
LYNXVILLE DAM 9            0.02        0700 AM  43.21N 91.10W
PRAIRIE DU CHIEN AWOS      0.01        0700 AM  43.30N 89.76W
SOLDIERS GROVE               T         0700 AM  43.39N 90.78W

...JACKSON COUNTY...
TAYLOR                     0.43        0700 AM  44.32N 91.12W
BLACK RIVER FALLS          0.20        0700 AM  44.38N 90.84W
BLACK RIVER FALLS RAWS     0.19        0700 AM  44.30N 90.84W
MATHER 3NW                 0.03        0700 AM  44.17N 90.35W

...LA CROSSE COUNTY...
LA CROSSE WFO                T         0700 AM  43.82N 91.19W

...MONROE COUNTY...
WARRENS                    0.10        0700 AM  44.10N 90.59W
FOUR CORNERS               0.07        0700 AM  44.07N 90.92W
SPARTA                     0.04        0700 AM  43.94N 90.82W
TUNNEL CITY                  T         0700 AM  44.01N 90.57W

...TAYLOR COUNTY...
LUBLIN DIAMOND LAKE        0.26        0700 AM  45.11N 90.69W
MEDFORD 4NW                0.10        0700 AM  45.21N 90.36W
MEDFORD                    0.10        0700 AM  45.13N 90.34W

...TREMPEALEAU COUNTY...
BLAIR 2NW                  0.55        0700 AM  44.31N 91.27W
OSSEO                      0.33        0700 AM  44.58N 91.22W
GALESVILLE 2ESE            0.23        0700 AM  44.08N 91.34W
TREMPEALEAU DAM 6          0.19        0700 AM  44.00N 91.44W

...VERNON COUNTY...
DESOTO 1SE                 0.04        0700 AM  43.41N 91.19W
GENOA                      0.03        0700 AM  43.57N 91.23W

OBSERVATIONS ARE COLLECTED FROM A VARIETY OF SOURCES WITH VARYING
EQUIPMENT AND EXPOSURE. NOT ALL DATA LISTED IS CONSIDERED OFFICIAL.

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