textproduct: Eureka

KEY MESSAGES

* Interior Valleys are expected to see a another chilly morning this morning with near freezing or freezing temperatures, while closer to the coast low clouds may limit the frost.

* Light rain is expected Sunday evening through Monday, mainly in Humboldt and Del Norte counties.

* Coastal flooding is possible Sunday, but more likely Monday through Wednesday at high tide, mainly around Humboldt Bay.

SYNOPSIS

Dry weather will continue through today. Another chilly morning is expected this morning, as well. There is a chance for rain in Humboldt and Del Norte counties Sunday evening through Monday. A persistent upper level trough is expected Tuesday through Thursday bringing highs only in the 60s or cooler. Rain is possible with chances increasing late in the week in the north.

DISCUSSION

Another chilly morning is anticipated for many of the valleys. A Frost Advisory remains in affect for Mendocino and much of Lake County. If the northern valleys of Mendocino County remain clear they may see freezing temperatures and this will need to be watched. The same will be true in Humboldt and Del Norte counties. Currently clouds look more likely in these areas, so frost advisories have not been issued for these locations. In Trinity County, an agricultural killing freeze has occurred. Thus, frost advisories and freeze warnings have been suspended this winter season for Trinity County.

Today, high clouds are forecast to begin trekking into the area ahead of an upper level trough and associated frontal boundary. Rain is possible as early as late this afternoon in Del Norte County. However, this is more likely to start by this evening in Del Norte County and spread south overnight into Humboldt County. Total rainfall amounts in Del Norte County are expected to range from a half inch to an inch. Humboldt County may see close to a half inch near the Del Norte County line with less than a tenth of inch in southeastern Humboldt. Eventually, some showers may make it farther south and east, but only a trace to a few hundredths is expected. There is a small chance for some thunderstorms late tonight in Del Norte County, but confidence is low on this and models have been trending the upper level low farther making it less likely.

Tuesday and Wednesday are generally expected to see dry weather, however it is a troughy pattern. This could bring a few showers, especially to the coastal counties. A mix of sun and clouds is likely in this pattern. This all is expected to keep temperatures in the 50s or 60s. Starting on Thursday most of the models are showing some rain, although the amounts vary on the clusters. The probability of over a half inch for any particular 24 hour period is less than 20 percent through late next week. Early November the models and the CPC forecast are starting to show the potential for a wetter pattern by November 3rd. MKK

AVIATION...06Z

VFR conditions are anticipated very early this morning for coastal terminals. However, a thin layer of coastal stratus is trying to form along the coast potentially bringing MVFR ceilings for the coast before sunrise. Cloud cover will increase across Northwest California the rest of today. VFR conditions are anticipated for most interior terminals, but some interior valleys could experience low cloud development before sunrise.

MARINE

Winds and waves are expected to continue to diminish early this morning. Today, winds are expected to become more southerly in the northern waters and gradually more westerly in the southern waters as a low pressure system passes by to the north. A few models show stronger winds in the northern waters and this will need to be watched as it gets closer. Southerly winds of 10 to 15 kts are expected in the northern waters late Sunday before turning northwest to north again early next week. These are expected to increase by Tuesday. These look to be slow to increase only reaching 20 kt in the southern waters by Tuesday night. These are expected to continue to increase on Wednesday before diminishing again late in the week. Winds are expected to be mainly wind driven but combining with a small northwest swell around 5 to 7 feet. MKK

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. As the northerly winds have diminish the current tidal anomaly has increased to 1.1 feet for todays high tide. The northerly winds are expected to continue to diminish tonight and Sunday. If the anomaly increases to just 1.3 feet minor flooding may occur. Monday the astronomical tide increases to around 7.8 feet. The anomaly is expected to increase as well and this could easily bring water levels to around 9.0 feet. Tuesday the winds start to turn back to the north. This may start to diminish the anomaly or keep it steady. This will be 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. This will likely bring at least minor coastal flooding and possibly moderate coastal flooding. This will mainly be around Humbodlt Bay with little expected outside the bay unless there are large waves. MKK3

EKA WATCHES/WARNINGS/ADVISORIES

CA... Frost Advisory until 10 AM PDT Sunday for CAZ109>114-118- 120.

NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 4 AM PDT Sunday for PZZ475.