HBC -
No, precipitation records, historic river levels, and other climate records remain the best resource.
And the geography hasn't changed.
The Upper Missouri receives most of its flow from the Northern Rockies.
Snow pack is the best predictor. Snow melt varies from year to year.
Early hot temps, esp. combined with heavy rain can prouce a huge surge as in 2011.
The Middle Missouri was dammed (or damned) under the Pick-Sloan Program in the 1950s and 1960s.
These reservoirs receive the Upper Missouri flow plus snow and rain runoff from the Northern Plains.
This region often receives half its annual precip in May & June - with the peak around June 1.
The three major tributaries of the Lower Missouri are the Platte, the Kansas, and the Osage.
Only the Platte has Rocky Mountain headwaters - plus, its waters are grabbed by Denver metro and agriculture.
All three rivers can rise rapidly during heavy spring rain runoff, but they also have major reservoirs.
Floods like in 2011 are a 100-year occurance.
Plus, dam management that spring was questionable.
Everybody knew the snowpack was huge - and then big rains came on top of it.
Of course, many areas of the Plains are semi-arid and the farmers don't was to release water.
Especially if the reservoir ends up never getting filled.
It's a crap shoot with pressure to store as much water as possible.
So, in 2011 the ACE folks were caught with their pants down.
I'd still use the climate records -
Although the Great Plains have a highly variable climate - one of the most variable in the world.
In the late 1800s, homesteaders were told the "Rain follows the plow."
http://plainshumanities.unl.edu/encyclopedia/doc/egp.ii.049Well, there was a nice wet decade - - followed by ten years of drought.
And most of the homesteaders went belly up.
Also, the MKT / Katy Railroad between St Louis and Kansas was notorious for flooding.
Even when it was still a railroad. Nice to be next to the river, but ....
You can do Highway 94 - but it has killer goathills. I know.
Back in 1987, I though it would be flat because it follows the river on a map.
Hah! Granny gear to big ring 100 times a day.
You should plan on rain since early June is the peak precipitation period.
It's just that the quantity is hard to predict - a little, a lot, or biblical.
https://www.weather.gov/eax/monthlypcpnHave a nice trip! Jama
