Significant rain and thunderstorms possible Sunday night into Monday as system moves in

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Posted at 3:41 PM, Dec 27, 2020
and last updated 2020-12-28 03:09:34-05

Sunday was beautiful on the Central Coast with partly cloudy skies and temps in the low 60's, but this is really the calm before the storm.

The first significant storm of the season will bring widespread rain and mountain snow to the region this evening through Monday night.

WOW take a look at the recorded rain over the last 2 hours in SLO County! We could see up to 1 inch (possibly more at this rate) in some places by Tuesday morning.

Posted by Megan Healy TV on Sunday, December 27, 2020

The system looks to arrive by 7 p.m. bringing rain first to northern San Luis Obispo County, but by 9 p.m. steady light to moderate rain is expected for much of the Central Coast.

We could see anywhere from 0.5 to 1.5" of rain by Monday night after the system passes through the area to the south and east. There could be some local pockets of 0.50 to 0.75" per hour under any thunderstorm or isolated heavier shower, according to the National Weather Surface which causes concern for recent burn scar areas, but no advisories have been issued yet in terms of that.

Models indicate good moisture supply and decent instability along the frontal boundary of the system which means there could be a chance of thunderstorms for coastal and valley areas.

This storm also has potential to bring 6 to 12 inches of snow about 5,000 ft. A Winter Storm Watch has been issued for the Santa Barbara County Mountains starting 10 p.m. Sunday and lasting until Monday night. Gusty Southwest winds 15 to 25 MPH with gusts to 40 mph are expected. Travel into the mountains should be avoided tonight and Monday as very cold and blustery wintry conditions with snow covered roads and reduced visibility with blowing snow is expected, especially above 4500 to 5000 feet.

A High Surf Advisory is in effect until 3 p.m. Tuesday for west and northwest facing beaches in San Luis Obispo and Santa Barbara Counties. Elevated surf of 8 to 12 feet with local sets to 14 feet is expected today and tonight. Surf will build to 10 to 15 feet with local sets to 18 feet Monday.

Temperatures will also cool down to about 5 to 10 degrees below normal on Monday with coasts and valleys likely remaining in the upper 50s to low 60s.

Monday night will be cold dipping into the upper 30's and low 40's which means frosts and freezes are possible.

There will be breezy offshore flow on Tuesday as the storm exits to the east. Weather looks to calm down Wednesday through next weekend and should be mostly sunny with temperatures close to normal.