* WHAT...Sub-freezing temperatures in the lower 30s possible.

* WHERE...The Northwest Valley of the Phoenix Metro Area, The East Valley of the Phoenix Metro Area, Buckeye/Avondale, Deer Valley, Central Phoenix, North Phoenix/Glendale, Scottsdale/Paradise Valley, South Mountain/Ahwatukee, and Southeast Valley/Queen Creek.

* WHEN...From Tuesday evening through Wednesday morning.

* IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing.