San Diegans walked out the door Friday morning to see an unfamiliar sight -- their own breath.
"You'll be wearing that jacket all day long," said NBC 7 Meteorologist Jodi Kodesh.
Mountain areas got hit with Friday's cold snap the hardest, with temperatures reaching below-freezing levels. The Mountain Empire Unified School District in the east county cancelled school Friday due to icy roads.
Inlands and coastal areas will reach the mid-50s Friday, but the mornings will certainly be chilly and the temperatures will plummet by the evening.
Even coastal temperatures may drop below freezing by the night.
"Sensitive plants will be lost, so if you have those, bring them inside," Kodesh said, adding that pets should be brought inside as well, if possible.
Winds made the cold weather a little harsher as well.
The NWS said a frost advisory would remain in effect from midnight through 8 a.m. Sunday.
That means very cold nights with frost and low temperatures for the next several mornings. Some of the coldest coastal areas may see temperatures fall below 28-degrees at one point.
At this time, the NWS expects Saturday to be the coldest night of all, with a hard freeze likely in some areas. The temps in the coldest areas are expected to range from 26 to 32 degrees. Downtown San Diego will see low temps in the mid to upper 30s.
The freezing temperatures have potentially debilitating effects on local crops. In Escondido, Farmer Mike Hillebrecht took time Thursday to prepare the thousands of oranges and avocados on his more than 100 acres of land.
He used a wind machine to help save his crop from the temperatures expected Friday. The wind machine draws warmer air from above and mixes with the cold air, which he says raises the temperature about five degrees.
And if you've been cold lately, imagine how your plants must feel.
Fausto Palafox with Mission Hills Nursery has some easy tips to help protect your outdoor houseplants from the cold.
Most nurseries and home centers sell protective covering for plants. Its esentially a thin covering to keep your plants toasty. They sell for about 15 dollars. He also says you can use a bed sheet or piece of burlap.
He says do not cover your plants with plastic. It can actually trap in the cold.
He also recommends watering your plants during the day when the sun is out. It will provide a bit of insulation.
Palafox also sells "Cloud Cover" spray, which is a spray-on coating to protect your plants. Its sells for 15 dollars.
And he also recommends sliding your plants under a patio covering or some other shield - like a bench - to protect plants from wind and rain.