The heaviest rains come later Saturday with thunderstorm potential Sunday

Wet Cambria Camera
Posted at 11:12 AM, Dec 10, 2022

The storm system the KSBY Weather Team has been talking about for more than a week is finally here.

Showers began last night and have continued into early Saturday but the main event really doesn’t arrive until later this afternoon into the early morning hours of Sunday. That time frame is when the cold front slides thru the area with higher rainfall rates.

I think rainfall rates of ¼ to 1/2 “ per hour are likely with some rates up to 1” per hour in the hill and mountains possible. This main frontal band did that in the Bay area earlier today and prompted some flood advisories, which is possible here as well.

Additionally, winds will be an issue from Saturday afternoon into Sunday morning.

There are two active advisories for that. A wind advisory from noon to 6am Sunday for the coast: 20 to 35 mph with gusts 40 to 50. The high wind warning has the same timing but: south to southwest winds 30 to 40 mph with damaging gusts up to 65 mph.

After the main frontal band passes the heavier rain will turn into scattered showers and scattered thunderstorms. There is a lot of cold air rotating around an upper-level trough which lingers in the area into Monday morning.

The Storm Prediction Center has identified the Central Coast as an area of thunderstorm potential later this evening and night for the northern part of SLO county and over the entire area Sunday. Storms which form will likely be scattered but can produce: lightning, localized strong winds and hail, and locally brief but heavy rainfall. The threat is listed as “marginal”.

When you add it all up, it looks like our forecast range of .50-2.0” of rain for most will work.

However, based on new modeling and storm history I think some 3+” rainfall is possible if not likely. Rocky Butte already has more than 2” and the main band isn’t even here.

Sunday night into Monday it gets cold and snow levels drop. There is a winter storm watch in place for the Santa Barbara County Mountains.

There is also a high surf advisory for the west-facing Central Coast from Sunday morning into Monday night at 8 for10-14ft foot sets with some max sets to 16ft. Dangerous rip is likely.

Following the system departure on Monday, temperatures don’t recover much: 50s and 60s for highs.

Some models are showing more rain chances around next weekend but there isn’t much alignment at this point. We are broad-brushing a chance either Friday or Saturday at this point.