According to the NWS forecasts, There will be record water-rising of the Arkansas River that could be catastrophic to those nearby.

40/29 News Chief Meteorologist, Darby Bybee, had the following to say about the Arkansas River's rising over the Memorial Day Weekend...

To better put this in perspective, the Arkansas River at Fort Smith & Van Buren will be at levels seen in 2015 by tomorrow afternoon, 1990 levels by early Saturday morning, exceeding record flood of 1945 by Saturday evening & cresting 3' above the record by late Sunday morning, according to latest forecasts from Tulsa NWS Hydrologists...

Now being that I'm not privy to the Arkansas River's rising history, I had depend heavily on the diagram below to get a clear picture of exactly what is forecasted to take place. See pic below provided by the National Weather Services.

According to the National Weather Service, by Sunday, the Arkansas River is now expected to rise 3 feet above the previous record levels in Fort Smith and Van Buren. That record was set in 1945.

It is strongly encouraged that Fort Smith and Van Buren residents take projected river condition seriously and evacuate ASAP where orders have been given.