Governor Tate Reeves said significant risks remained in parts of the state.
Hundreds of people have been displaced in the wake of the tornadoes which tore through Mississippi and Alabama on Friday night.
The mayor of one of the worst affected towns said he had lost personal friends in the disaster.
Friday's tornado was the deadliest in the state of Mississippi in more than a decade. At least 25 people have died in the state, with one person confirmed dead in neighbouring Alabama.
Trees have been uprooted, trucks have overturned into houses and power lines have been brought down by the tornado - classified as "violent" and given the second-highest rating possible.
On Saturday, survivors of the disaster could be seen walking around, dazed and in shock. Sunday, on the other hand, has been a hive of activity.
Volunteers, some coming from neighbouring Arkansas, Louisiana and Tennessee, have been helping with the clean-up operation.
President Joe Biden has declared a state of emergency and deployed federal resources to help with the rescue and response in some of the worst-hit towns.
The devastation is so great, it must be difficult to know where to begin. Crews are working to remove broken trees that are pinning down power lines, with thousands of people losing power during Friday's storm.
Stations have been set up outside some of the few buildings still partially standing where people can collect water and sandwiches.
But while local communities are grappling with the response, there are warnings of further severe storms to come.