Step aside, mild autumn a cold front racing down the coastline will bring freezing temperatures to the Central Coast through the weekend, and possibly a dusting of snow early Saturday morning on the highest peaks.
Residents should protect their pets, their plants and themselves against overnight temperatures that by early Thursday morning could drop into the low 20s in North County and the low 30s in the coastal areas and San Luis Obispo, PG&E meteorologist John Lindsey said.
At the holiday parade scheduled for Friday evening in downtown San Luis Obispo, It will definitely be Christmassy, Lindsey said.
The Prado Day Center Warming Station for the homeless will be open Wednesday through Friday nights.
A cold air mass that originated in Canada will bring the chill, according to the National Weather Service.
Public safety officials remind residents to heat their homes in safe ways don't bring the barbecue inside, for one thing and to check on family and neighbors who might be at risk.
Plants should be watered, because cold air can suck moisture out of them.
While the cold is good for roses, maples and other plants that drop their leaves in autumn, that is not the case for tropical plants, such as bougainvillea and hibiscus, and evergreens such as citrus and avocado.
Sensitive young trees can be covered with burlap, sheets or other fabric, using stakes to keep the cloth from touching the branches. Nurseries also sell sprays that guard against frost, and gardeners can string Christmas lights through the branches to add a little warmth.
The Modesto Bee contributed to this report.