Here is my forecast for now through midnight. Readers in east central and southeast Iowa should really keep an eye on the weather the next few hours. Giant  hail (≥4") likely if supercell thunderstorms develop. So, I would urge you to put your car in the garage along with anything else that can be damaged by hail. I also believe it is quite possible for a tornado or two if supercell thunderstorms develop. If you have friends/relatives in the purple area, please make sure they are aware of the threat. Here is the radar at 3:37pm.

There are two areas that need to be watched later today and tonight. Let's start with the threat in the East. That threat is caused by the remains of tropical storm Bill, an unusually tenacious storm. It has been spinning small tornadoes since it came on shore.  The Mississippi Valley threat is the more serious. In addition to tornadoes, there is an enhanced risk of damaging winds and large hail. Residents of this area really need to keep an eye on the situation. I will update the situation at least once this afternoon.

Just stay away from I-35 and the flooding this afternoon and evening Reason #1. This is what northbound I-35 looks like in Murray Co. where it is closed due to the rockslide. Reason #2. I-35 in both directions may have to be closed at the Texas-Oklahoma border due to record flooding on the Red River. Of the available choices (which are hardly ideal), U.S. 81 is upstream (west) of the flooding and probably the better choice.

Again, today's risk is in the northern High Plains and Black Hills. The brown area has the significant risk. Also, therein the potential for very large hail and wind gusts of 75 mph or higher in the hatched area.

Fortunately, it is a small geographic area today. If you live in these areas, please keep up on the weather this afternoon and tonight.

As you have seen from the national news this morning, catastrophic flooding has occurred throughout north Texas and southern Oklahoma. Here are two hydrographs showing flood stages near I-35 in southern Oklahoma. If you live near these or the other rivers for which flood warnings are in effect, follow the guidance of local authorities. Regardless of what else you may do, do not try to cross flooded areas by foot or by car! Turn around, don't drown.