Monday was a bit on the breezy side across south-central and southeast Wisconsin.
Sustained wind speeds were in the 20 to 30 mph range with gusts to around 45 mph.
There were reports of broken tree branches and in some cases old, rotten trees came down. According to newspaper reports, WE Energies reported about 7,000 customers lost power mainly due to tree limbs blowing into power lines. The hardest hit area seemed to be on the north side of Milwaukee, with around 2,800 customers without electricity. Dust was blown off some farm fields due to the dry weather conditions in the past 30-45 days. The Milwuakee U.S. Coast Guard rescued 6 kayakers within the Milwaukee harbor area after their kayaks capsized in choppy waters.
A Wind Advisory was issued at 340 am CDT for most of south-central and southeast Wisconsin for gusts to around 45 mph. A Gale Warning for the nearshore waters was issued at 322 am CST Monday June 18, 2012. Gale Warnings are for wind gusts in excess of 35 knots (40 mph). The Gale Warning was preceded by a Small Craft Advisory which was issued at 942 am Sunday June 17, 2012.
The strong winds were generated by a strong surface pressure gradient over the southern Great Lakes region which was due to the large air pressure difference between a low over northern Minnesota and a high over the Eastern U.S. Seaboard.
Below is a surface weather map for 1 pm CDT Monday:
Daytime heating and mixing of the atmosphere between the ground and about 5000 feet above the ground level allowed strong winds to mix down to the surface. Wind speeds are usually stronger above the ground level due to less frictional drag created by the ground.
Below is a listing of some of the peak sustained wind and wind gust values.
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
858 PM CDT MON JUN 18 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
0201 PM NON-TSTM WND GST 6 WNW KENOSHA 42.62N 87.93W
06/18/2012 M45.00 MPH KENOSHA WI ASOS
0210 PM NON-TSTM WND DMG 3 W BROOKFIELD 43.06N 88.18W
06/18/2012 WAUKESHA WI TRAINED SPOTTER
FOUR-INCH DIAMETER TREE BRANCH SNAPPED OFF FROM BASE OF
TREE DUE TO NON-THUNDERSTORM WINDS.
0220 PM NON-TSTM WND GST NNE KENOSHA 42.58N 87.82W
06/18/2012 M44.00 MPH KENOSHA WI OFFICIAL NWS OBS
39 KNOT WIND GUST RECORDED AT KENOSHA LAKESHORE MARINE
0235 PM HIGH SUST WINDS 2 N JUNEAU 43.44N 88.70W
06/18/2012 M30.00 MPH DODGE WI AWOS
0345 PM NON-TSTM WND GST 4 SSW JANESVILLE 42.63N 89.05W
06/18/2012 M43.00 MPH ROCK WI AWOS
0345 PM NON-TSTM WND GST 2 E HOLY HILL 43.24N 88.29W
06/18/2012 M44.00 MPH WASHINGTON WI TRAINED SPOTTER
0353 PM NON-TSTM WND GST 2 NW RACINE 42.75N 87.81W
06/18/2012 M43.00 MPH RACINE WI ASOS
0415 PM NON-TSTM WND GST 3 ENE MONROE 42.62N 89.59W
06/18/2012 M45.00 MPH GREEN WI AWOS
0524 PM NON-TSTM WND GST 1 W WHITEWATER 42.83N 88.76W
06/18/2012 M44.00 MPH WALWORTH WI MESONET
UNIVERSITY OF WISCONSIN-WHITEWATER
Kapela/Townsend WFO Milwaukee