Update from KSBY Chief Meteorologist Dave Hovde:
The heavy rain has started to wane over SLO county but as of 9:34p there were still some stronger showers in Santa Barbara County. This activity will also diminish soon. Some on and off showers are possible overnight but in general, we are on the back side of this system.
In terms of rain, this is a look at the 12-hour totals. I'm choosing 12 hours since we are really trying to look at how much rain was associated with this cold front passage and not the light mist and drizzle which has lingered since Thursday.
There are also some significant changes to the advisories. The changes are detailed in this post from my social media:
——————From the prior story posting————————
The long-awaited New Year's Eve storm is marching thru California today. Already the Bay Area has been drilled with some of the heaviest rain they've seen in a 24-hour period.
That line of rain entered the Central Coast around 1:30pm (light showers have been falling since Thursday but we are referencing the heavier rain with the frontal boundary).
The Central Coast will likely see a few hours of intense rain and wind from the afternoon into the early evening before the front moves out of the area.
The rain rates could be .50-1"/hour. Some flooding can't be ruled out if the high rain rates happen, and the risk would be higher if the front was not moving so quickly thru the area.
Thunderstorms aren't likely but definitely possible.
Additionally, winds are up. An advisory and a warning are in place until later this evening. SW winds 20-30 with higher gusts have prompted a wind advisory for most of the area with higher elevations experiencing 25-35mph sustained winds with gust potential to 60. Those higher winds have prompted a high wind warning.
The winds have put energy into the water. Higher swells and surf are likely into Monday. A high surf advisory is in place.
The Weather Prediction Center has coastal California identified as an area at risk for some excessive rainfall, including the Central Coast. The Bay Area has already seen that, so we'll be watching the frontal passage carefully.
After this event winds down tonight, New Year's Day looks dry with the sun coming back out eventually. Highs in the 50s to low 60s Sunday.
Monday rain returns, light rain early but later Monday into Tuesday another .50" is possible. Then a brief break before a much larger storm Wednesday or Thursday.
All models like this particular storm to have big potential. If you add up all rain from now thru next weekend, most models show 2-5" with some models peaking at 6-7".
This is all possible due to atmospheric river connections. This is the upper atmospheric wind plus moisture transport.
A number of these connections to active low-pressure systems are likely. Today is an example of one of these events.