Severe Outlook Monday/Monday NightJune 30th, 2014 at 2:35 am by Bill Steffen under Bill's Blog, News, Weather
Click on the Graphics to enlarge. The map on the left is the Storm Prediction Center Severe Outlook for this afternoon/tonight. The red is the Moderate Risk area, which has been expanded in West Michigan (Ottawa, Allegan, Van Buren, Berrien and Cass Counties). It also covers much of N. Illinois, SE Wisconsin, Iowa and N. Missouri. The Slight Risk is in yellow, and that covers most all of Lower Michigan. The green-colored areas are areas where general non-severe storms are expected. The 2nd image is the chance of a tornado within 25 miles of a given point, highest in Iowa. Much of Lower Michigan is in the 5% category. The third map is the probability of a wind damage report within 25 miles of a given point. That’s the most significant threat here in Michigan with a large part of West Michigan in the 30% category (moderate risk is 45% chance). The final map is hail probabilities, highest as storms initiate in Iowa and N. Missouri. While we have a chance of a t-storm through the day, the most likely time for the strongest storms will be in the evening, after sunset. SPC says: “LARGE HAIL…TORNADOES…AND POTENTIALLY WIDESPREAD DAMAGING WINDS ARE EXPECTED ACROSS THE REGION LATER TODAY AND TONIGHT……A POTENTIALLY WIDESPREAD DAMAGING WIND THREAT COULD EVOLVE ACROSS PORTIONS OF IA AND NORTHERN MO INTO IL/SOUTHERN WI AND POSSIBLE LOWER MI/NORTHERN INDIANA DURING THE EVENING/OVERNIGHT HOURS. THIS SETUP COULD YIELD FAIRLY NUMEROUS SUPERCELLS THAT WILL HAVE THE POTENTIAL FOR UPSCALE GROWTH INTO A DERECHO-PRODUCING MCS.”. Here’s the SPC full discussion. The next update from SPC is scheduled around 12:30 pm EDT. I’ll be updating the blog when I can – watch 24-Hour News 8 as we continue to track this potential severe threat. See threads below for useful links and radar. Here’s the latest GRR NWS discussion. Live radar is several threads down from this one.
I think Iowa and N. Illinois will have the greatest threat of severe weather this PM and early tonight. Here’s today’s storm reports – by 11:20 am, we’ve already had 1 tornado, 4″ diameter hail and winds over 70 mph.