* WHAT...Sub-freezing temperatures as low as the upper 20s expected.
* WHERE...Southern Clinton, Southern Lycoming, Union, Snyder, Montour, Northumberland, Columbia and Schuylkill Counties.
* WHEN...From 2 AM to 8 AM EDT Saturday.
* IMPACTS...Freeze conditions will kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing.