A massive shift in the weather pattern is in progress and will continue to bring much-needed rain and mountain snow to southern California. Though this would seem to be great news for areas suffering from the recent wildfires, too much rain too quickly can cause mudslides, especially to burn-scarred areas.
A large area of low pressure will slowly head eastward today and be over the Desert Southwest by midweek. As part of a gigantic weather pattern change, this storm will pack abundant Pacific moisture into cities that have been devastated by raging wildfires. Today will see rain fall at times from Santa Barbara to Santa Clarita, Los Angeles, and as far south as San Diego, Calif. There could even be a few rumbles of thunder.
By the time the storm moves on off to the east late today, one-half inch to 1.5 inches of rainfall will be possible along the Interstate 5 corridor in southern California. This amount of rain will be beneficial for the short-term drought and fire situation and will be the first rain many of these areas will have seen in almost 9 months. Localized flooding and even some mudslides will be possible. In fact, Flood Watches and Advisories remain in effect for portions of southern California. Remember to follow a simple motto if you approach a flooded roadway, “Turn Around, Don’t Drown!”
While Pacific moisture causes rain for the low elevations, the Sierra Nevada Mountains will see snow falling.
Winter Weather Advisories and Winter Storm Warnings remain in effect over the Sierra Nevada into the Transverse Ranges in southern California, as well as for parts of Nevada and northwestern Arizona. Four to 8 inches of snowfall will be possible, with locally more than a foot could pile up! An inch or two of snow may also accumulate in some of the passes, such as the Tejon Pass on Interstate 5, making travel difficult across the region.
As mentioned before, for portions of southern California this is first rainfall of the so-called wet season. Drought conditions, spurred on by Santa Ana winds, worsened over the past couple of weeks. This has caused dry vegetation that made excellent fuel for the recent large and deadly wildfires.
It’s never too early to have a supply kit packed in case of inclement weather. A simple kit including a weather radio, water, blankets, batteries, and non-perishable food items will go a long way in the event of a power outage. It’s always best to avoid travel in rough weather as the roads will be dangerous.