Point St. George to Cape Mendocino CA out 10 NM Marine Forecast
|Today...N Winds 5 To 15 Kt. Waves Nw 9 Ft At 12 Seconds.
|Tonight...E Winds 5 To 10 Kt. Waves Nw 8 Ft At 12 Seconds.
|Wed...S Winds 5 To 15 Kt...Rising To 15 To 20 Kt. Waves Nw 6 Ft At 11 Seconds. Slight Chance Of Rain.
|Wed Night...S Winds 20 To 30 Kt. Waves Sw 7 Ft At 6 Seconds.
|Thu...Sw Winds 15 To 25 Kt. Waves Sw 13 Ft At 9 Seconds. Rain, Showers And Isolated Tstms.
|Fri...Sw Winds 15 To 25 Kt. Waves W 17 Ft At 15 Seconds. Showers And Isolated Tstms.
|Sat...Sw Winds 10 To 15 Kt. Waves W 5 Ft At 6 Seconds...And W 13 Ft At 16 Seconds.
| Area Forecast Discussion
National Weather Service Eureka CA
555am PST Tuesday Feb 27 2024
Cooler air settled in this morning behind a front tonight. A multifaceted, powerful and very cold storm system will then unleash brief heavy rain, strong winds, heavy snowfall and small hail Thursday into the weekend.
The boundary layer is effectively decoupling this morning with robust radiational cooling dropping coastal temps into frosty and some freezing levels. The forecast for a major winter storm is largely on track. On Wednesday a deepening, cold trough will begin descending from the north. Rain chances will increase from north to south throughout Wednesday under increasing upper diffluence. Southwest winds will strengthen Wednesday afternoon and become strong by early Thursday morning. A High Wind Watch is out for gusts up to 65 mph on the ridgetops. An Advisory may also be needed for lower elevations not included in the watch. A strong cold front with an IVT plume will then arrive Thursday. The front will initially deliver a round of widespread moderate rainfall, with a briefer period of heavy rainfall for portions of the North Coast and on some favored higher terrain.
Sounding analysis shows the potential for a sharp drop for snow levels by around late Thursday morning. This colder scenario is looking more likely given the adiabatic and dynamic cooling in part from the orographic lift from the strong southerly winds. Moreover, some high resolution guidance is resolving heavy rainfall rates along a banding feature which could drive down the cold air aloft. Have lowered snow levels Thursday to include the Willow Creek and Hoopa Valley where sounding support exist for now for at least light snow impacts. There will be a warm nose ahead of the front which will further complicate this aspect of the forecast.
The dynamic, very cold trough will continue to descend in, bringing waves of embedded disturbances and fronts which will steadily drive down snow levels. This looks to include a couple small surface lows which could locally enhance precipitation and winds, depending on where the track. Total precipitation has slighlty decreased for the event through the weekend when the trough axis passes through. Snow levels of 500 to 1000 feet are most likely in Trinity, Del Norte, and Humboldt early Saturday morning. Even south in Mendocino and Lake snow levels of 1000 to 1500 feet are most likely. The most likely snowfall forecasts Friday through Saturday still shows multiple feet at high elevation locations like Collier Tunnel and Berry Summit. The Prairie Creek pass on 101 and stretches of 101 near Laytonville in Northern Mendocino County can expect snowfall and travel delays. NBM shows a 30 to 50% chance of accumulating snow as low as Clearlake in Lake County and Blue Lake in Humboldt County early Saturday morning. Increasing instability and forcing, along with the very cold air aloft will also create an environment favorable Friday into Saturday for dangerous and widespread accumulating small hail. JJW
Northerlies strengthened behind yesterday`s frontal passage with gusts in the low to mid 20 mph range. Advisory level northerlies will generally diminish, but persist into the early tomorrow morning, especially in the southern waters. A fresh NW swell fills in around 12 ft at 13 seconds. Seas are expected to trend downward by mid-week, but will soon build back Thursday and into the weekend as a series of fronts approach. A large W swell is expected late this week, with wave heigheights reaching around 20 ft.
.EKA WATCHES/WARNINGS/ADVISORIES... CA... High Wind Watch from Wednesday evening through Thursday afternoon for CAZ101-102.
Winter Storm Watch from late Wednesday night through Friday morning for CAZ102.
High Wind Watch from late Wednesday night through Thursday afternoon for CAZ104>106.
Winter Storm Watch from Thursday morning through Friday morning for CAZ105-106.
Winter Storm Watch from Wednesday evening through Friday morning for CAZ107-108.
Winter Storm Watch from Thursday afternoon through Friday morning for CAZ111-114.
NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 9am PST this morning for PZZ450.
Gale Watch from Wednesday evening through Thursday morning for PZZ450-470.
Small Craft Advisory until 2am PST Wednesday for PZZ455- 475.
Small Craft Advisory until 6pm PST this evening for PZZ470.