textproduct: Eureka

KEY MESSAGES

* Dry, cooler, and breezy conditions are expected today with frost or freezing temperatures possible tonight into Saturday morning.

* There is the potential for a pattern change to cooler and wetter weather early next week.

SYNOPSIS

Dry weather arrives today and likely through the weekend. Cool and breezier conditions are likely today with near to below freezing temperatures possible tonight. Warm and dry conditions are expected Saturday. The next chance for rain for Humboldt and Del Norte is expected by late this weekend into early next week.

DISCUSSION

The upper low that brought rainfall over northwestern California over the last few days finally moves out of the area today. A dry cold front brings in much drier and cooler air into the area, and also breezy northwesterly winds. Gusts of 20 to 30 mph are possible along the coast this afternoon and evening. Breezy northeast winds are possible in eastern Lake County and along the exposed ridges.

Widespread valley fog and lingering high clouds from the upper low will prevent a widespread frost early this morning. However, clearing skies Friday and offshore flow building in the evening and overnight will promote a much colder night across the area. Much of the interior valleys could see low temperatures in the high 20s to the mid 30s. Even the coast, especially a few miles inland, could see temperatures in the mid to high 30s as well. Frost will be possible for much of the interior valleys outside southern Mendocino and Lake, where winds will keep temperatures slightly higher.

A relatively warm and dry day is expected Saturday across the area with high pressure at least temporarily rebuilding. There is still a lot of uncertainty on the pattern Sunday into early next week. Around 25% of models still paint a troughing pattern with a weak front arriving Sunday evening or night, bringing rain to Humboldt and Del Norte. The remaining 75% of model solutions show high pressure remaining at least into Monday. Interior high temperatures Sunday may be in the high 60s or low 80s depending on which pattern winds out and how much cloud cover we receive. The pattern remains chaotic into early next week with a near 50/50 split between a ridging or troughing pattern. In terms of potential precipitation, on Sunday there is around a 20% chance of wetting rain (over 0.1") in Del Norte and much lower chances elsewhere. On Monday, there is around a 20 to 40% chance of wetting rain over Del Norte and Humboldt Counties. Chances for wetting rain diminish mid next week, but more wet weather is possible late next week, but model guidance remains just as chaotic. Stay tuned! JB

AVIATION...(6Z TAFs)

The upper low bringing rain over the area is quickly moving out of the area. A dry cold front is expected to gradually diminish cloud cover over the night. Still, lingering MVFR ceilings are possible through the early morning. Areas of fog, especially in the sheltered inland valleys, are possible from the recent rains. Any lingering cloud cover or fog is expected to diminish after sunrise. Breezy northwest winds are likely at the coastal terminals and may near or exceed 30 kts, especially at KCEC.

MARINE

Northerly winds are quickly increasing behind a dry cold frontal passage late Thursday evening. Gale force gusts are likely in the outer waters into the evening today. The northern inner waters are likely to see widespread gale force gusts early this morning through late morning. While winds diminish below gales in the inner waters, winds will remain breezy up to 30 kts through the afternoon, with locally higher winds possible around Point St. George. Steep seas of 9 to 13 ft are expected with these winds. Winds and seas diminish Saturday into Sunday as a low pressure system approaches north of the area. JB

FIRE WEATHER

A much drier airmass arrives today into Saturday as an upper low exits the region. More widespread breezy offshore winds are expected over the higher terrain this evening and overnight. Winds will be most widespread in the higher elevations of Lake County and eastern Mendocino Counties. Overnight recoveries outside the valley floors are likely to be poor given these offshore winds with maximum RHs in the 20s and 30s. While elevated to locally critical fire weather conditions are likely in the highest terrain, recent rains may limit the impact of these conditions somewhat. JB

COASTAL FLOODING

High astronomical tides associated with the full moon will bring chances for coastal flooding around Humboldt Bay starting as early as Sunday with chances continuing through next week. Astronomical tides at the North Spit tide gauge reaches 7.49 ft MLLW on 11:26 AM Sunday. With the tidal anomaly currently running 1.0 to 1.5 ft above forecast, minor coastal flooding is possible at these levels. The highest astronomical tides, and highest chances for coastal flooding, are forecast to be on Tuesday and Wednesday of next week at 8.04 ft and 8.06 ft, respectively. JB

EKA WATCHES/WARNINGS/ADVISORIES

CA... Freeze Watch from late Friday night through Saturday morning for CAZ108-110-111-114-116-117.

NORTHWEST CALIFORNIA COASTAL WATERS... Gale Warning until 9 AM PDT Friday for PZZ450.

Small Craft Advisory until 9 AM PDT Saturday for PZZ455.

Gale Warning until 3 AM PDT Saturday for PZZ470.

Gale Warning until 9 PM PDT Friday for PZZ475.