As a quick glance at the Weather Channel reveals, the upper Mississippi basin is facing historic flooding right now.
Now, last I checked, the eastern Rockies snowpack was heavy and melting, so there is water coming from the west into the basin, not just north.
The Ohio is not flooding the way it was, but rivers west of the eastern continental divide are flowing at a healthy clip, mainly due to residual rain from the line of storms that is flooding the north - unlike the east side of the eastern continental divide which is broadly below normal, still.
All this water will come down the Mississippi, which will flood.
The flood crest will disperse as it propagates down river, which mitigates the flooding, as does the levee breaking up-river. The breaking levees let flood waters spread laterally onto flood plains which disperses the flood crest further, bad for local flooding but reduces downstream flooding in the longer run.
So, by the time it get to the lower basin the flood could be modest. We'll know in a few weeks.
The danger, still, is if tropical gulf moisture now comes down in front of or on top of the flood crest in the south - which can happen if the jet stream shifts a little.
Still a low probability event, since several things have to happen at just the wrong time, but that it is possible at all this year is reason to keep an eye out.
Don't want heavy rains or tropical storms to start dumping Arkansas or Louisiana as the northern floods get there.
We were in New Orleans a little over a month ago. The river was high then. They were opening flood gates to let the river into Lake Pontchartrain.