June 18, 2015: Tropical Storm Bill has been stirring up plenty of trouble with rain and wind since it made landfall in Texas earlier this week, and we may feel some of those impacts in our region. One of the advantages of living in the Midwest is NOT having to deal with tropical storms and hurricanes. However, every once in a while, one holds together just enough to provide the Midwest with a little rain.
You can see here that Bill started over the warm, moist air of the Gulf of Mexico, and made landfall this past Tuesday. Sustained winds were around 40 mph, but the wind gusts were in the 60 mph range. As Bill moves north, the storm will weaken, since the very warm and humid air of the Gulf won’t be feeding it any more. The storm essentially weakens into a strong low pressure system, similar to ones we get around here to bring us rain. What’s neat is that southern Illinois will be getting a taste of Bill this weekend! The storm will not be nearly as strong, as you can see.
While Bill brings blustery winds, the bigger impact is the rainfall Bill is able to provide. In fact, with most hurricanes and tropical storms, its not the winds that do the most damage, like you would think. It’s the rain and flooding this storms can create. You can see in the radar image from Thursday evening that numerous flash flood warnings are out (in maroon), though a few severe thunderstorm warnings are occurring too (in orange).
Here’s the 48-hour rainfall totals from the the stretch Bill has covered. This doesn’t capture all of the rain Bill has dropped, but you get a decent picture that these storms can drop a ton of soaking rain, especially since they move pretty slow (Bill is only moving north at 11 mph), allowing the heavy showers to sit on places until they are flooding. In fact, some areas in Texas saw 6″ to 10″ of rain, while in Oklahoma, certain areas had 4″ to 8″ of rainfall!
Bill will be much weaker by the time the storm reaches Illinois this Saturday, but a possible 2″ or more of rain may still fall as the weakening storm moves eastward. The Stateline should be a little too far north to get rainfall from Bill, though we may get to see some of the clouds streaming off the storm over our area, which is a neat bonus. It’s not often we get to say our weather is being influenced by a tropical system in these parts!
This post was written by Alex Kirchner on June 18, 2015