——— 8:00AM Update———-
Heavy rain has started to fall across the Central Coast. Here is an update from Meteorologist Vivian Rennie.
The main storm system has arrived on the central Coast and will bring heavy rain in the morning hours, significant rain began along the north coast around 7AM and is continuing to push into the region. It will likely be raining heavily in the San Luis Obispo area by 8:30 am and the 5 Cities shortly thereafter. By 9 rain will have moved into Santa Maria and it will continue to push SE quickly through the morning.
Good Morning Central Coast! Today is going to be a very impactful weather day with heavy rain, gusts and thunderstorms expected. Be sure to stay weather aware and keep up to date on the forecast.
Jumping right in...
When rain started yesterday we were just seeing the initial portion of the storm kicked off by the passing cold front. Now that the front has passed we have access to much more unstable air and the deeper core of low pressure. This has already created heavy rain overnight in the bay area and will shift south into the Central Coast before dawn.
Cooler and gusty conditions will combine with the heavy rain to make for a messy commute. Thanks to added upper air instability The Storm Prediction Center has identified much of California as being at "marginal" risk of convection. For us this means scattered thunderstorms that bring increased heavy rain, lightning, thunder, and scattered hail potential. There are no severe watches at this point for that potential activity.
There are two active advisories for winds in our region. The first is a High Wind Warning for the interior valleys, including Cuyama Valley, San Luis Obispo County Interior Valleys, San Luis Obispo County Mountains and Santa Barbara County Interior Mountains. From 6 AM to 6 PM PST Tuesday Southwest winds 25 to 35 mph with gusts up to 50 mph are expected
Elsewhere a wind advisory is in place through 1PM Tuesday afternoon. This will bring slightly calmer winds than in the warning area but still significant.
Another advisory in effect is a high surf advisory in effect untill 9 am Wednesday for large breaking waves of 8 to 11 feet with local sets to 12 feet with dangerous rip currents. Highest on the west and northwest-facing beaches.
The additional rain potential is still significant. When we look back at this system we'll likely get that .50-2+" of rainfall that we at KSBY have been forecasting.
I think if we were to massage the forecast a little it would be to include the potential for some isolated areas of 3" rainfall. Because of the convective nature of this second part of the system, I'd expect a wide variety of reports all along the forecasted accumulation range. While we can show maps of deterministic outlooks (ones where a town has a specific rain value), it is always best to prepare for the range.
Some snow accumulation is possible at the highest elevations in our area, but it is a larger issue elsewhere like The Grapevine and The Sierra.
The system will be most impactful Tuesday and start to taper late, some scattered shower potential is possible early Wednesday but we should be working our way out of the system by then.
The rest of the week looks quiet but there is some disagreement about the outlook for the coming weekend. The American GFS likes dry but the EURO likes showers. The ensemble models aren't a lot of help either, they essentially can't align. Generally, when you get an outlook like this you opt for dry until there is better agreement. For now, I'll go with dry but don't be stunned if rain enters that weekend forecast.
Have a great day Central Coast!