Miss. Code § 63-3-515
The boards of supervisors of counties and the governing authorities of municipalities are hereby authorized to adopt by order or resolution and to enforce within their respective territorial boundaries the maximum legal rate of speed at which a motor vehicle may be run or operated along any public street, road, highway (except state-maintained highways), or portion thereof in the vicinity of schools and churches, upon levees and causeways and in other special zones which the board or governing authorities may designate. The rate of speed so established shall be determined upon the basis of an engineering and traffic study. The order or resolution setting such speed limits may provide that such limits are only effective during specified times of the day, days of the week and months of the year.
Miss. Code § 63-3-515