A weak weather system brought a little drizzle and light rain to some areas this morning.
We have another weak system coming through later on Sunday. This could bring some very light rain, mainly to northwestern San Luis Obispo County. Amounts will be minimal, if any.
Weather through Monday: Prepare for Wind
- Gusty Northerly Winds: The main weather story is a prolonged period of gusty northerly winds, lasting through early next week for the Southcoast, but even a bigger concern for Ventura and Los Angeles counties.
- Wind advisories are in effect for many of these areas, and there's a chance we might see some low-end high wind warnings issued.
- Prolonged elevated surf: A high surf advisory continues thru Tuesday for the west-facing Central Coast for waves up to 15ft, lower to 8-11 feet Sunday and continuing thru Tuesday.
Temperature Fluctuations:
- Saturday: Expect a warmer day on Saturday, with temperatures rising 3-6 degrees.
- Sunday: It will be cooler on Sunday as that weak system moves through.
- Less Fog: We're less likely to see widespread low clouds and fog during this period of northerly winds, but some patchy fog is still possible.
New Year's Day and Beyond: Santa Ana Winds Arrive
- Transition to Santa Ana Winds: Starting Tuesday, the northerly winds will begin to shift to a Santa Ana wind pattern. This change will become more noticeable on New Year's Day and could last through the end of the week.
- Santa Ana winds are warm, dry winds that blow from the northeast. They occur when high pressure builds over the Great Basin (think Nevada).
- Where the Winds Will Blow: The Santa Ana winds will mainly funnel northwestern Los Angeles County and southern Ventura County but we’ll have to keep an eye on this in Santa Barbara county. These winds might be weaker than the preceding northerly winds. However, wind advisories are still expected, especially in the normally windy areas.
- Temperature Impacts:
- Warmer Near the Coast: Coastal areas and coastal valleys will experience much warmer temperatures during the offshore event, here on the Central Coast we should see some 70s and mid-70s might be possible.
- Cooler Inland: Interior areas like inland San Luis Obispo County will be cooler due to the lack of downslope warming that occurs with offshore winds further south.
- Chilly Nights: Overnight lows will be quite cold, with some areas dipping below freezing.
Technical Notes (for weather enthusiasts):
- The northerly winds are driven by a combination of factors, including the movement of weak weather systems and the position of high and low-pressure areas.
- The transition to Santa Ana winds is caused by a trough (an elongated area of low pressure) moving through the Pacific Northwest and down into the Great Basin. This sets up a pressure gradient that drives the offshore flow.
- The strength of the Santa Ana winds is influenced by the pressure difference between the Great Basin and the coast ("northeast gradient") and the support from winds aloft.
Bottom Line:
The Central Coast can expect a very minor shower chance Sunday, and some offshore winds next week but not as notable as SoCal.
