Valley residents would be wise to bundle up and cover their plants as a freeze warning tonight and Tuesday morning will usher in 2013.
A cold-air mass will settle over the Valley this evening, driving temperatures below freezing in a lot of areas.
The National Weather Service issued a freeze warning from midnight tonight until 8 a.m. on New Year's Day.
The affected areas include southwest and south-central Arizona including Casa Grande and Gila Bend. Sensitive plants that are vulnerable to frost damage should be cared for appropriately.
A freeze watch has been posted for many desert areas from the Colorado River east to Phoenix and Casa Grande for late Monday night and Tuesday morning. Several hours of widespread freezing temperatures are possible.
Clearing and colder weather will develop Tuesday morning with widespread temperatures near freezing in many desert locations. In fact, some overnight readings in the Valley could plunge into the upper 20s.
New Year's Day will see highs generally in the 50s under partly sunny skies.
In addition, no-burn restrictions are in effect in the Phoenix metropolitan area Monday night due to high particulate levels in the air.
The restrictions include a prohibition on burning wood in fireplaces, outdoor stoves, chimneys and fire pits.
Air quality officials say they recognize that New Year's Eve is a big evening for recreational activities, but they urge people to abide by the restrictions to protect public health.
Copyright 2012 CBS 5 (Meredith Corporation). All rights reserved. The Associated Press contributed to this report.