Thunderstorms from eastern Will County, Illinois moved into northwest Indiana, reaching Cedar Lake Indiana, in west central Lake County Indiana by 245 pm CDT, Tuesday afternoon, May 15, 2007. As the thunderstorms crossed the Illinois - Indiana border, National Weather Service Dopper radar showed a very strong outflow wind. This wind produced the damage in Cedar Lake Indiana Tuesday afternoon. This damage included several downed trees, snapped telephone poles, and roof damage at a Day Care School. A survey team from the Chicago National Weather Service Office concluded that the damage in
Figure 1. This is the radar reflectivity of the thunderstorm moving into Cedar Lake Indiana. Looking at the picture you can see Cedar Lake, just north of Lowell Indiana. This picture was at 245 pm CDT. The orange and red colors indicate a lot of rain and possibly hail.
Figure 2. This is a velocity image from the Radar at the Weather Service Office in Romeoville Illinois. The red and orange colors indicate out bound velocity (away from the radar). The green and blue colors indicate inbound velocity (towards the radar). The orange to bright orange colors approaching Cedar Lake Indiana show 45 to 60 knots of wind or 52 to 69 mph. The wind was elevated in this picture or about 2500 ft above the ground. This wind did descend to the ground causing the damage at Cedar Lake.