* WHAT...For the first Freeze Warning, sub-freezing temperatures as low as 30 expected. For the second Freeze Warning, sub-freezing temperatures as low as 27 expected. * WHERE...The northwest Piedmont, northeast Piedmont, and northern Coastal Plain. * WHEN...For the first Freeze Warning, from 3 AM to 8 AM EST Saturday. For the second Freeze Warning, from 1 AM to 8 AM EST Sunday. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. Take steps now to protect tender plants from the cold.