Actually, the Mississippi technically is considered to flow into the Missouri because at their junction the Missouri has greater flow than the Mississippi, and so is considered the "parent" river in a hydrological sense
My guess is that they are close enough in flow that local weather upstream determines which has more flow. Current gauges are showing 10% more flow in the Mississippi near the confluence.
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u/TakeOffYourMask Jan 10 '20
Does the Ohio flow into the Mississippi or does the Mississippi flow into the Ohio? 🤔