A very powerful bow echo has tracked across Iowa and is now entering Illinois as of this early afternoon, leaving behind a wide swath of destruction thanks to numerous reports of wind gusts over 80 mph. There have even been reports over 100 mph in Iowa, leaving over 365,000 without power from PowerOutage.us.
As a result of the strength of this bow echo, a rare PDS Severe Thunderstorm Watch has been issued until 7:00 PM. PDS stands for ‘Particularly Dangerous Situation’ and is only applied from the NWS when needed. A bow echo capable of producing widespread gusts over 80 mph meets this criteria.
We have to stay weather aware until about 8:00 PM or so this evening for mainly a wind threat. Tornadoes are possible, but they are hard to track in these types of events due to them being embedded within strong, straight line winds. Treat these storms as if they are tornado warned.
Due to the storms themselves moving at 70 mph, our forecast models are way too slow with the timing, so we won’t put a slideshow together. Below is an example of what it could look like around 4:00 PM, a whole two hours quicker than what the model thinks.