UPDATE (10:00 a.m.) - Hello, Central Coast. Here’s an update of what we can expect to see in the forecast as another round of storms makes its way back to the Central Coast this weekend!
Here are some of the latest weather headlines occurring across the area: There were some isolated showers this morning in some areas of the Central Coast, but mostly dry weather is expected from now through Saturday morning. A strong and wet storm system will arrive Saturday late afternoon or evening. However, this storm will bring heavy rain and mountain snow to much of California through at least Tuesday morning, with showers possibly lingering through midweek. Let's dive in!
Earlier this morning, skies were partly to mostly cloudy with some isolated to scattered showers occurring region-wide as there continues to be a fast west to northwestly flow behind the front that moved through the area on Thursday.
Overall, there should be a drying trend kicking off on Friday, so expect a decrease in showers and partly cloudy skies for most areas of the Central Coast this afternoon. There will be some gusty west winds on the coast, but winds should remain below advisory levels in most areas.
It will be quite cool across most of the area today, with high temperatures topping out in the lower to possibly mid-60s in the warmest locations, which is several degrees below normal.
A strong and cold upper low off the coast of Washington state will move little today and then drop slowly southward tonight and Saturday, reaching west of the California/Oregon border late Saturday afternoon. As this occurs, the mid and upper-level flow will turn westerly. Then there will be a fair amount of low-level moisture, so expect skies to be partly to at times mostly cloudy tonight. However, expect little precipitation tonight.
On Saturday, moisture will increase throughout the atmosphere, so expect clouds to increase during the day, with skies becoming mostly cloudy north of Point Conception during the morning, and then elsewhere during the afternoon. There will be increasing mid-level lift along with the moisture on Saturday, especially north of Point Conception as a warm front begins to develop. There will be an increasing chance of rain during the day across San Luis Obispo and most of Santa Barbara counties, mainly in the afternoon.
The upper low will continue to drop southward Saturday night, then move slowly southeastward on Sunday. As it does so, it will begin to elongate in a north-to-south fashion, with a trough axis extending southward through the eastern Pacific. The flow aloft will become more southwesterly Saturday night and Sunday and will begin to tap into some subtropical moisture as an atmospheric river aims the region. Precipitable water values will increase to about 1.2 inches to the west of the forecast area on Sunday.
Moisture will continue to increase throughout the atmosphere Saturday night and Sunday as southwesterly flow strengthens aloft, and a deep layer of strong moist southerly flow develops over the region. Rain will fall across San Luis Obispo and Santa Barbara Counties on Saturday evening, then spread southward, reaching at least western portions of Los Angeles County late Saturday night. Rain will likely become heavy at times late Saturday night and Sunday morning across San Luis Obispo County and much of Santa Barbara County.
During Sunday, rain is likely across the entire region, and will likely be heavy at times, especially from Ventura County northward where the best moisture and lift will be aimed. With increasing low-level southerly flow, there will be robust orographic enhancement of the rainfall on and below the south side of the transverse mountain ranges such as the Santa Ynez Range and Topatopa Range.
This weather pattern will continue Sunday night, with heavy rain continuing to fall across much of Santa Barbara County and a good portion of Ventura County. Rainfall rates of one-half inch per hour are likely for many hours in a row with this moisture plume, with local rates to an inch per hour possible on and below south-facing slopes. Significant roadway flooding is expected to develop late Sunday evening. Most smaller streams will fill quickly after the rain begins creating flooding of local roads. The Ventura River has at least a 25% chance of reaching flood stage by Monday morning. Even the larger rivers like the Santa Ynez and Santa Clara Rivers will likely see significant rises as well.
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Original Story (4:46 a.m.) - Hello, Central Coast! We’ve finally made it to the weekend. Happy Friday! We’re expecting to see more rain as we head into the weekend. We are expecting dry weather for most areas on Friday and Saturday except for some scattered light showers, mainly north of Point Conception and in the mountains. A second and likely much stronger storm will arrive Saturday night and Sunday with periods of moderate to heavy rain through at least Tuesday and perhaps Wednesday. A High Surf Advisory remains in place for both San Luis Obispo and Santa Barbara Counties through this weekend. Let’s dive in!
There is a possibility we could easily see more showers Friday for Santa Barbara and San Luis Obispo Counties along with light precipitation lingering for the Ventura County mountains and near the I-5 Corridor.
Some scattered light showers are expected to occur in the mountains and north of Point Conception on Friday and most of the Central Coast is expected to remain dry Friday and Saturday. However, gusty west winds up to 40 mph are expected to kick up by late morning along the coast south of Pt Conception. With skies clearing and cooler air settling in, overnight lows Friday night are expected to drop several degrees from the previous nights with lows in the 30s and 40s for much of the areas near the coast and valleys.
There’s a chance we will see the next band of rain heading to the Central Coast by early as late Saturday afternoon or during the evening. This would mainly be in the form of warm frontal rain which is typically on the lighter side, though in this case with strong moisture advection due to the presence of the atmospheric river and the development of very strong low-level forcing from on the south-facing mountains, rainfall is expected to be very heavy at times.
Models have indicated that we could see a lengthy period of heavy rain develop late Saturday night and continue through most of Sunday and Monday. Rainfall rates are expected to easily reach a half inch per hour, especially in the south-facing mountains. Most smaller streams will fill quickly after the rain begins creating flooding of local roads. The Ventura River has at least a 25% chance of reaching flood stage by Monday morning. But even the larger rivers like the Santa Ynez and Santa Clara Rivers will likely see significant rises as well.
A High Surf Advisory remains in place for both San Luis Obispo and Santa Barbara counties through Saturday until 5 pm. An extended period of high surf will continue to impact the beaches. High surf will persist through Sunday or Monday. We saw large waves on Thursday and we are expecting that on Friday as well. All west-facing beaches will see surf over 8 feet, with the Ventura Coast peaking at 12 feet, and the Central Coast at 18 feet.
The largest storm of the season will begin late Saturday night into Sunday as an upper low is expected to spin down the coast and merge with another upper low moving in from the west. Much of the rain of expected to stick with us through at least Wednesday.
Have a great day, Central Coast! Please be cautious and weather-aware this weekend. Don't forget to download the KSBY Microclimate App for the latest weather headlines.
