Midwest/Iowa Flooding

[J West]

Information regarding road closures in Wisconsin can be found here: http://dot.wisconsin.gov/travel/incident-alerts.htm

I-94 WB is closed in Waukesha and Jefferson County due to flooding of the Rock river in Jefferson County. I-39/90/94 WB is closed from north of Madison to Mauston due to flooding. There are detours in place, but this significantly delays interstate system travel....if you aren't local or don't have a good map, good luck.

The southern 1/3 of the state picked up another 1-6 inches last night/this morning with more coming over the weekend.

 

[Kenny Drake]

This is possibly the worst flooding Iowa has ever seen as many records are broken. Does anyone for sure know if this is the worst flood in our history for Iowa or even the midwest? I know 93 was bad and I know we also had a bad flood in the 40's.

Yes this thread is very quite for the historic flooding that is occuring.

I'm not quite sure how (statistically) the scale of a flood is determined. I'm guessing there is a time factor, space factor, and magnitude. I know a lot of rivers in Iowa are cresting above the previous record (many of those held since the '93 flood.) This may very well be the worst flood Iowa has seen in recorded history but I do not think it is at the scale of the 1993 flood which encompassed a much larger area.

Here are the stats on the 1993 flood for future reference (from Wikipedia):
Damage: $15 billion
Flooded area: 30,000 sq miles or 80,000 sq km

The 1993 flood basically lasted from April to July so from a timescale perspective I think this current flood will not be as bad. The long range models show the east coast ridge breaking down along a east coast trough/west coast ridge scenario. It is argued that the 1993 flood was an effect from a 1991 volcanic eruption. April, May and the beginning of June is generally very wet in Iowa and the player was the stationary front which has been "hanging around" the area for almost a month now.

The future crest of the Mississippi River in St. Louis will be a great gauge to compare against the 1993 flood. From NWS Flood Warning statement:

* FORECAST...THE RIVER IS FORECAST TO CREST NEAR 39.4 FEET FRIDAY
* IMPACT...AT 49.6 FEET...RECORD CREST AUGUST 1ST...1993.

In northern MO and southern IA the Mississippi River will likely crest very near the 1993 records. In 1993 the Missouri River was much more overloaded than currently.

All in all, it looks like Iowa and much of the Plains and Midwest will get some time to dry out thankfully.

 

[MatthewCarman]

The Birdland Levee in Des Moines has FAILED. Water has breached the Levee and is racing towards the 200+ houses below. A mandatory evacuation is currently underway.

They are talking about minimizing desease by giving out tentnis shots. I guess the water is not safe to walk or swim in.

 

[MatthewCarman]

Looks like more rain on the way for this already flooded area. SPC is expecting initiation across most of central Iowa in the next 1-2 hours and storms are starting to pop up by Boone and Nevada just north of Des Moines. They could become severe later.

 

[Joel Wright]

Looks like more rain on the way for this already flooded area. SPC is expecting initiation across most of central Iowa in the next 1-2 hours and storms are starting to pop up by Boone and Nevada just north of Des Moines. They could become severe later.

A few of the storms have become severe and dropped some fairly large hail. A few reports of golfball sized hail and 60-70mph winds in Tama country recently.

You're right, these storms are in about the worst possible location. Luckily PWs are low, and the storms are pretty scattered so heavy rainfall is fairly local. It's hard to get a good read on what these storms are putting out since the doppler radar indicated QPF is full of "hail contamination". With flash-flood thresholds so low it won't take much for that to become an issue.

Another concern is what happens tonight as the LLJ kicks in and deeper moisture returns. Boundaries from the current storm activity may help to focus storm development as well. Obviously where this ends up setting up will be HUGE in what happens later tonight...

 

[Angie K Holliday]

Two bridges crossing the Mississippi are closing tomorrow morning. One of the bridges to Quincy is closing, but they're keeping the other one open for now. Louisiana MO is where the other bridge is. I don't know too much about that one. The one up in Keokuk, IA is down to 2 lanes and they're working hard to raise the driving surface to keep it open. I'm hoping they can keep the bridge in Hannibal, MO open, because that's how my husband gets to work. I haven't been out to see much of this, really thinking I should try to get out sometime to see the flooding for myself.