The Mississippi River began cresting Tuesday in Memphis, but the slow passage of water working its way from north to south along the river is only the beginning for residents who could be dealing with high water levels into June.
The river measured 13.78 feet above flood stage as of 5 a.m. today, according to the National Weather Service, and water levels could rise or fall slightly, CNN meteorologist Jacqui Jeras said.
The Mississippi is the highest it has been at Memphis since 1937, when it crested at 48.7 feet - 14.7 feet above flood stage.
President Barack Obama signed a disaster declaration for Tennessee on Monday that will help direct federal aid toward recovery efforts in areas hit by severe storms, flooding and tornadoes since early April.
Once the crest is past Tennessee, it will target Louisiana and Mississippi, where residents and authorities continued preparations for river levels that could break records set in 1927, when flooding displaced 600,000 people and caused the equivalent of nearly $624 million in damage, according to the National Weather Service.
The river's crest is expected to begin arriving in Louisiana next week, CNN reported.
Flooding also continued to be a problem in southeastern Missouri and southern Illinois, even though the Mississippi and Ohio rivers have crested in those states.
Click here to see video of the flooding.