Morning commuters should watch out for black ice that can form. The CHP says if motorists hit black ice they should take their foot off the gas pedal and off the break and guide the car as best as they can with the steering wheel.
Other frost warnings include: bringing pets indoors, pipes should be covered to protect from freezing, and delicate plants should be covered. People should also check on the elderly during these freezing conditions.
Many people are concerned about protecting their plants and on Monday people were snatching up garden blankets to help protect their sensitive plants, but -- as some know -- there are also ways to protect plants with household items.
There is a special group of ladies that are plant experts, each one being a certified master gardener. They know when freezing temperatures in the mountains hit the valley floor, precious plants are at risk.
"You know what happens with frost damage, is that cells in the plant's leaf, actually freeze and then the cell walls explode," says Roberta Barnes, a master gardener.
Roberta says preventing that horrible fate actually begins with a few key secrets.
Tips to protect your plants:
- Water your plants in the morning before freezing temperatures are expected. Hydrated plats retain heat better.
- Cover your plants with professional garden blankets, regular blankets, a sheet, or cardboard box. Use stakes or some other devise to keep the material off the plant itself. Do not use plastic.
- Wrap your trees in Christmas tree lights and leave them on. This can help bring some heat to the plant.
- Move potted plants closer to the home or a protected area.
- Wait until spring before pruning limbs of the plants. The tips, though they may look dead, may come back after the winter.
"You need to keep the cover off the plant so it's not touching the plant. The cold will go directly through the cloth so if you have it sitting above the plant at least six inches you're better off," says Abby Garner, a master gardener.
That advice is also what you will hear from hotline volunteers at the University of California cooperative extension in Santa Clara County. Carole Frost is the program coordinator. She says larger plants such as a citrus tree can even get protection from an unlikely source.
"If you put Christmas lights in the canopy of the tree, that will bring up the temperature just enough so that you won't have frost damage," says Frost.
Moving potted plants close to the house or to a protected area also helps. The good news, not all frost damage is fatal.
"Sometimes frost damage will kill a plant, sometimes it will only stunt it or give you a little bit of pruning, so to speak and will come back to life when the weather warms up in the spring," says Barnes.
If a plant has frost damage, you may be tempted to cut off those unattractive branches or leaves, but don't do it. When the next frost comes, those limbs will help protect the plant. Leave the plant as is and wait until spring to see if it comes back or to prune it.