textproduct: Eureka

KEY MESSAGES

* Light rain Saturday night and again Monday afternoon in Del Norte and Humboldt counties. * Minor to near moderate coastal flooding is likely around Humboldt Bay from November 8th to 10th.

* Breaking waves of 20 to 25 feet are expected Sunday and these may coincide with a very high tide generating significant wave run-up.

* Stronger storm systems with more rain possible starting late next week.

SYNOPSIS

Southerly winds are expected to increase this afternoon with some light rain expected in Del Nort county this evening, spreading south into Humboldt county overnight. A series of weak fronts is expected to bring occasional light rain Monday through Thursday. The potential for heavier rain increases late in the week.

DISCUSSION

The current forecast is showing rainfall amounts in Del Norte county less than a half inch for tonight through Sunday late afternoon. These amounts are expected to diminish quickly to the south and east. Humboldt Bay and the Eureka area may see around .20 of an inch at most through Sunday late afternoon. Southerly winds are expected to increase with gusts of 20 to 30 mph possible in Del Norte county late tonight and diminish by early Sunday morning.

Sunday once any lingering showers move out in the north, dry weather is expected across the area. The clouds may take some time to clear, especially in the north. Fairly widespread low clouds are expected in the valleys in the north and it is uncertain how far south these will make it.

Another front is expected Monday afternoon. Again this looks like it will mostly impact northern Humboldt and Del Norte counties. Southerly winds will increase again with this one as well, with gusts to around 25 mph over the higher terrain in the north. Nearly an inch of rain is expected in the mountains of Del Norte county, but the amounts drop off quickly to the south and east. The NBM shows a 40 percent probability of rainfall over an inch in the Del Norte Mountains. Less than a 0.2 inch is expected in the Eureka and Humboldt Bay area.

Tuesday and Wednesday are now expected to see mainly dry conditions with a break between systems. Three of the four ensemble clusters show no rain and the fourth only shows some light rain. The models are showing some weak ridging, but the wind field remains light. This will likely yield some warmer temperatures, but the humidity may remain higher with more clouds around.

Thursday and Friday the models have backed off about 24 hours on the expected rainfall from yesterday. The heavier now looks to be late Friday and Saturday. So the trend of the models keeping the significant rain around day 8 continues. Two of the model clusters are showing 1 to 2 inches in the 24 hours ending at 4pm on Saturday. MKK/EYS

AVIATION...18Z TAF

A trough to the north will deliver a weak front tonight. Light rainfall will develop after 6Z for the North coast, but CEC may see TEMPO moderate rainfall. Ceilings should drop into MVFR levels with the rainfall. Stronger winds aloft farther north will also bring some low level wind shear up to 30 kt through 1500 to 2000 ft AGL around CEC. Lingering light rainfall and showers will quickly clear out from 14Z to 16Z Sunday, but the MVFR CIGs may be slower to clear out through 18Z Sunday. Some IFR level ceilings have developed in the subsidence ahead of the trough. The trough looks to sufficiently deepen the marine layer to enter UKI from the higher terrain to the west, threatening CIGs at or below 1700 ft AGL. RRFS guidance depicts this scenario, with later clearing from 16-17Z Sunday.

MARINE

Southerly winds increase across the waters as a trough passes with moderate to fresh breezes over mainly the northerly waters. These will quickly ease late tonight behind a passing front.

The main concern is a large WNW swell that will quickly build in tonight. The swell will reach 17 to 20 ft by Sunday morning, with a period up to 17 seconds. The swell will then ease Sunday night through Monday. Southerly fresh breezes develop again Monday with another front.

BEACH HAZARDS

A large swell of 16 to 20 feet at 17 seconds is expected to arrive Sunday morning creating large breaking waves of 22 to 24 feet for NW facing beach through the day. A High Surf Advisory remains in place for this threat. Extra caution is advised near beaches this weekend due to the increased swell activity. Extra wave runup is possible on N CA beach as the sand profile responds to swells this large again. Stay safe by being aware of these potential hazards.

COASTAL FLOODING

Water levels inside Humboldt Bay continue to run 1.2 to 1.3 feet over the astronomical tides. Southerly winds on Saturday may increase these slightly with water levels inside Humboldt bay reaching 8.8 to 9.0 ft on Sunday. The large swell on top of this high water may impact some areas even inside Humboldt Bay.

Outside of Humboldt Bay on the open coast, Crescent City and Arena Cove tide gauges are running 0.5 to 1.0 feet above astronomical tides. The southerly winds may increase this slightly too. These are expected to remain below flood advisory levels; however, the large breaking waves may briefly flood roads and parking lots that are exposed at high tide. MKK

EKA WATCHES/WARNINGS/ADVISORIES

CA... High Surf Advisory from 4 AM to 10 PM PST Sunday for CAZ101- 103-104-109.

Coastal Flood Advisory from 10 AM to noon PST Sunday for CAZ103.

NORTHWEST CALIFORNIA COASTAL WATERS... Coastal Flood Advisory from 10 AM to noon PST Sunday for PZZ415.

Small Craft Advisory until 3 AM PST Sunday for PZZ450-470.

Hazardous Seas Warning from 3 AM to 8 PM PST Sunday for PZZ450-470.

Small Craft Advisory until 4 PM PST Monday for PZZ455.

Small Craft Advisory until 9 AM PST Sunday for PZZ475.

Hazardous Seas Warning from 9 AM to 8 PM PST Sunday for PZZ475.