textproduct: Eureka

SYNOPSIS

Dry conditions will continue across the area today. A frontal boundary will bring gusty to strong south winds late tonight through Tuesday afternoon. Light to locally moderate showers on Tuesday through Tuesday night, with lingering showers through Wednesday afternoon. Rain chances returns Friday and through the weekend as another frontal system approaches from the west.

KEY MESSAGES

* Gusty to strong south wind gusts from 35 to 50 mph are expected late tonight through Tuesday afternoon over the coastal headlands and exposed ridges in Del Norte and Humboldt.

* Light to locally moderate showers are forecast on Tuesday, with lingering showers through Wednesday afternoon.

DISCUSSION

Partly to mostly cloudy skies were observed across the northern portion of the area overnight as a weak shortwave moves through, while clear skies has developed for Mendocino and Lake counties. Low dewpoints, clear skies, and light winds are promoting efficient radiational cooling across the interior valleys. A Cold Weather Advisory is in effect until 9AM this morning for apparent temperatures at or below 30F degrees across the interior valleys in the southern portions of Mendocino and southern Lake counties. Opted not to include the interior valleys in Trinity due to slightly warmer conditions compared with the last 24 hours, where low temperatures in the upper 10s to low 20s were observed.

High pressure build back quickly in the wake of the passing shortwave trough today, with conditions slightly warming up. The pattern shifts as the ridge finally breaks down giving way to a broad, upper-level trough moves into the NEPAC. A shortwave trough and cold front embedded to trough will approaches the area tonight through Tuesday. A cold front will traverse the area from west on Tuesday. This will bring light to locally moderate showers on Tuesday. Generally 0.10 to 0.50 inch is forecast from late Tuesday afternoon through Wednesday afternoon, with the bulk of the precipitation expected Tuesday afternoon through Tuesday night. Locally 1 to 1.5 inches is forecast over the south- southwest windward-facing terrain in Del Norte and Humboldt counties, with the highest amounts in the King Range. There are no major impacts expected with this weather system; if precipitation does occur, it would be more beneficial than impactful, especially after the recent dry spell.

In addition, a frontal boundary will bring gusty to strong southerly winds late tonight through Tuesday afternoon. Gusts from 35 to 50 mph are likely over the coastal headlands and exposed ridges in Del Norte and Humboldt counties. As results, a Wind Advisory is in effect from 10 PM tonight through 4 PM PST Tuesday.

High pressure is expected to rises over the area on Thursday, promoting dry weather and above normal temperatures. Ensembles models, and WPC Cluster Analysis suggests (25-35%) another shortwave trough may bring another chance of light showers for the northern portion of the area by late in the work week and/or through the weekend. The EPS and GEFS show the next weekend rain totals look to be below 0.1" for each 24 hours period Friday- Sunday. /ZVS

AVIATION...(6Z TAFs)

VFR conditions are expected to prevail overnight with only high clouds expected. Some patchy ground fog is possible, but impacts to the terminals are expected to be minor. Any fog will dissipate shortly after sunrise. Southerly winds are likely across the area in the afternoon and could be breezy around CEC with gusts possibly up to 20 kts. JB

MARINE

Southerly winds will increase across the waters today with widespread gusts of 20-25 kts likely by the afternoon. Winds continue to increase tonight into Tuesday, with gales likely in the outer waters and nearshore from Cape Mendocino northward. Steep seas of 6-10 ft are possible with these winds. Locally higher seas of up to 14 ft are possible in the northern outer waters. Winds ease below gale force Tuesday night and short period seas will start to subside. However, a large, long period westerly swell will arrive Wednesday afternoon into Thursday, bringing combined seas of 14-16 ft. Winds remain southerly for the remainder of the week and are likely to remain breezy north of Cape Mendocino. JB

EKA WATCHES/WARNINGS/ADVISORIES

CA... Wind Advisory from 4 AM to 3 PM PST Tuesday for CAZ101.

Wind Advisory from 1 AM to 3 PM PST Tuesday for CAZ102-105- 106.

Wind Advisory from 10 PM Monday to 4 PM PST Tuesday for CAZ104.

Cold Weather Advisory until 9 AM PST Monday for CAZ113-115.

NORTHWEST CALIFORNIA COASTAL WATERS... Gale Warning from 3 AM to 3 PM PST Tuesday for PZZ450-470- 475.

Small Craft Advisory from 3 AM to 3 PM PST Tuesday for PZZ455.

Small Craft Advisory from 10 AM Monday to 3 AM PST Tuesday for PZZ470-475.