The latest forecast for severe weather conditions from the Storm Prediction Center (SPC), issued at 8:24 a.m. Monday morning, shows the highest probability of strong thunderstorms on a treadmill across southwest and southwest Lower Michigan. General forecast of strong storm for 8 in the morning Monday to 8 in the morning of Tuesday. The orange area is called “enhanced risk”. (source: Storm Prediction Center) The orange shaded area south of a Muskegon to Detroit line is in what is called an “enhanced risk” area for severe storms. A strong storm forecast can also be considered a five-level forecast. The enhanced risk is level three on this five-level scale. The scenario we are expecting is an accumulation of storms that are developing this afternoon in South Wisconsin. The storms are then expected to spread southeast to southern Lower Michigan. This series of storms will probably be only a hundred miles long from north to south. The series of storms could have points that take what the Storm Prediction Center calls “catastrophic gusts of wind.” The following is the forecast of severe weather conditions, which is divided into specific types of severe weather conditions. The first forecast is for straight wind gusts. These strong gusts of wind come in the first 10 minutes of a storm. The black trail from Muskegon and the southwestern shoreline of Lake Michigan to near Ann Arbor and Detroit has the potential for gusts of 75 mph or greater. At 80 mph, gusts of wind cause significant damage to buildings and can even break windows. Not a sure bet, but if the storms become intense, they could cause short, very intense gusts. Strong wind forecast for Monday afternoon and Monday afternoon. The black hatching area has a 10 percent chance of bursting 75 mph or higher. There is also a fairly high risk for some tornadoes, not just linear winds. The same area with the highest risk of strong gusts of wind also has the highest risk of a tornado. Tornado probability forecast for Monday afternoon and Monday night. Heavy hail is possible, but not the main concern right now. Large hail forecast indicating a one inch diameter hail probability TIME OF STRONG THUNDERSTORMS Thunderstorms should enter the western side of Lower Michigan sometime between 4 p.m. and 7 p.m. We are not sure yet. We will know early in the afternoon. It will then take about three hours to watch the storms in southern Lower Michigan. Here are the cities with the highest risk of severe storms: Muskegon, Grand Haven, Holland, South Haven, Benton Harbor, Grand Rapids, Battle Creek, Kalamazoo, Lansing, Jackson, Coldwater, Adrian and Ann Arbor. North of Grand Rapids in the Flint area there is still the possibility of strong gusts of wind, but it should be more isolated and not as strong. The storms may weaken some as they move through the Detroit area, but I will watch that too.
