* WHAT...Sub-freezing temperatures as low as 29 to 32 possible. * WHERE...In Alabama, Butler, Conecuh, Crenshaw, Monroe, Wilcox, Choctaw, Clarke, and Washington Counties. In Mississippi, Wayne County. * WHEN...From late Friday night through Saturday morning. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing.