Marine Weather Net

Point St. George to Point Arena between 150 and 250 NM Offshore Forecast


TONIGHT

N
WINDS
15 - 25
KNOTS

MON

N
WINDS
15 - 25
KNOTS

MON NIGHT

N
WINDS
15 - 25
KNOTS

TUE

N
WINDS
15 - 25
KNOTS

The Marine Weather Forecast In Detail:
PZZ920 Forecast Issued: 823 PM PDT Sun Apr 21 2024

Tonight...N Winds 15 To 25 Kt. Seas 7 To 11 Ft.
Mon...N Winds 15 To 25 Kt. Seas 7 To 12 Ft.
Mon Night...N Winds 15 To 25 Kt. Seas 7 To 11 Ft.
Tue...N Winds 15 To 25 Kt. Seas 6 To 11 Ft.
Tue Night...N Winds 10 To 20 Kt. Seas 5 To 9 Ft.
Wed...N To Nw Winds 10 To 20 Kt, Diminishing To 5 To 15 Kt. Seas 4 To 7 Ft.
Wed Night...Nw Winds 10 To 20 Kt, Becoming W To Nw 10 To 15 Kt. Seas 6 To 7 Ft.
Thu...W Winds 10 To 20 Kt. Seas 6 To 7 Ft.
Thu Night...W Winds 15 To 20 Kt, Becoming Nw. Seas 6 To 8 Ft.
Fri...Nw Winds 15 To 25 Kt. Seas 7 To 9 Ft.
Fri Night...Nw Winds 15 To 20 Kt. Seas 7 To 9 Ft.
SHARE THIS PAGE:           
Area Forecast Discussion
National Weather Service Eureka CA
310pm PDT Sunday April 21 2024

Synopsis
Dry weather with above normal temperatures are expected to continue through Monday. Isolated thunderstorms are possible for mostly Trinity county on Tuesday as daytime temperatures begin to trend down. Much cooler temperatures, a chance for rain and high mountain snow will return Thursday through Friday.

Dry weather with temperatures well above late April normals will continue across NW California through Monday. Large scale subsidence and drying tonight coupled with moderate to locally robust offshore wind flow tonight into Monday will likely yield localized low RH's tonight. Monday is shaping up to be the warmest day so far this spring with temperatures peaking in the mid to upper 80s for the interior valleys. Probabilities for lower 90's for a few of the hotter locations in NE Humboldt, Trinity and Mendocino Counties are around 30-40%, though Big Bar may top out around 92F (NBM probability of 70-90%). Even coastal areas will warm up on Monday, mostly mid to upper 60s. A bit inland away from the cooling sea breezes, temperatures will likely (>70% chance) hit the lower to mid 70s.

Breezy to locally windy north winds along the coast this afternoon and evening are forecast to diminish tonight. ARW and other high resolution models continue to indicate locally gusty E-NE developing later tonight into Monday morning as an inverted trough develops and high pressure shifts inland. Per the HREF and NBM, a few localized gusts to 30-40 mph are probable (>60% chance) over some the exposed ridges and higher terrain.

On Tuesday, a 500mb shortwave trough will approach the Pac NW. A semi-closed low in the southern branch of the split will also start to spread higher PWATs (Precipitable Waters) (200% of normal or close to 1 inch) into the area from SW. Deterministic models (GFS, NAM12 and ECMWF) continue to indicate increasing buoyant energy and instability for possible (25-35% chance) for showers and thunderstorms across the interior (mostly Trinity County) on Tuesday.

Also, a closed cyclonic circulation evident at 925mb will likely induce a southerly wind reversal and a push of marine air and low clouds from the south Monday night into Tuesday morning. Some cooling is expected on Tue, but high temps will likely remain above normal until the air mass cools down more drastically toward the end of the week.

Potential for precipitation will increase Thursday-Friday as a colder 500mb trough (temps <-25C) drops down from the NW. Timing has tightened up to Thu- Fri with 24 hours probabilities for > 1 inch in 24 hours for the western slopes of Del Norte and northern Humboldt Counties around 30%. Highest chances for precipitation are forecast across the interior of Del Norte County (~1 inch over 2 days) with the lowest in southern Mendocino and southern Lake where only a few hundredths may accumulate over 2 days. There is still a great deal of variability with timing and precipitation amounts. For now will highlight the major cool down and precipitation potential in weather story graphic/social media posts.

A secondary trough in the NW flow on the backside of the main trough may spark up more showers Friday night into Saturday (10-20% chance). It is more certain that interior high temperatures will cool down by late week. If snow levels fall to 5000-5500 feet on Friday, high temps will struggle to reach the lower 40s in the high mountains on Friday and may not recover much next weekend. Precipitation amounts are forecast to be light, but this time of year even light amounts will have impacts on outdoor plans or activities. Stay tuned. ZVS/DB

Marine
Northerly wind will continue to strengthen this afternoon with increasing coverage of gale force gusts. The strongest gusts are expected in the far northern waters this evening with gusts up to 40 kts. Gale gusts are expected to extend into the inners right near Cape Mendocino and Pt. St. George, although coverage looks to be <50% of the zone. Strong wind will support the formation of steep short period seas in excess of 10 feet through the night tonight.

Building high pressure over the interior will help shunt strong winds further offshore Monday through midweek, brining calmer conditions at least to the near shore waters. Short period wind waves will dominate the sea state except for a series of minor mid period northwest swells up to 5 feet persisting through the week. TDJ

.EKA WATCHES/WARNINGS/ADVISORIES... CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 9am PDT Monday for PZZ450.

Small Craft Advisory until 9pm PDT this evening for PZZ455.

Small Craft Advisory until 3pm PDT this afternoon for PZZ470.

Gale Warning until 9am PDT Monday for PZZ470.

Gale Warning until 9pm PDT this evening for PZZ475.