Update: 8:47pm from KSBY Chief Meteorologist Dave Hovde
The frontal boundary which triggered showers across the area today has mostly moved out of the area and broad activity has ended, though some widely scattered showers are still possible.
As expected, the rainfall amounts were generally light. Rocky Butte along the SLO County north coast (a high elevation) got the most rain at .44". Some other locations managed a tenth or two, but the bulk of reports at lower elevations were only in the hundredths of an inch.
Cold air behind this frontal boundary is conditionally unstable, meaning we could see some isolated to scattered showers on Wednesday, but very hit and miss and more missing than hitting. Just don't be shocked if some cumulus form for a quick shower. This is not the emphasis of the day's weather. It'll be a cool to cold day outside of the Southcoast. I talk more about frost potential in the coming days further down in this story.
A snow shower can't be ruled out in the Santa Barbara county mountains (at high elevations) as we get into Wednesday morning. Higher elevations elsewhere in CA have a better snow opportunity.
————from the prior story——————-
The rain system we have been pondering for more than a week is finally here, but locally it doesn't appear there is much rain potential.
(note: as it is still raining this is an incomplete report. I'll update it later)
Models vary in terms of expectations but we are at the tail end of a frontal boundary which is also moving quickly.
All those factors generally lead me to lean toward the lower end of expectations on rain accumulation. I think we'll see light amounts (some with 0 accumulation) to .25", it is possible some isolated spots could exceed that but not generally.
The frontal boundary is already thru the area before 11 pm. After that, the large upper trough of low pressure sweeps into the region. This is a significantly large and cold trough. High temps the next couple of days (other than the Southcoast in SB County) will likely stay in the upper 50s and lower 60s.
Frost will not be a concern tonight but Wed-PM to Thu-AM, Thu-PM to Fri-AM, and Fri-PM to Sat-AM frost will be possible in the interior valleys.
Daytime highs warm Friday and Saturday and slip a little Sunday.
There are more rain chances next week. The American GFS model now suggests systems: Monday, Wednesday, and Friday. All look to be quick hitters, splash and dash systems but at least it is something.