textproduct: Eureka

KEY MESSAGES

* Near to slightly above average temperatures inland continue today with the warmest temperatures in Lake County.

* A passing cold front brings a high chance of light rain to Del Norte and northern Humboldt late Thursday night into Friday.

* Breezy winds possible late Thursday and into Friday.

* Cooler temperatures will arrive this weekend behind the front, bringing chances for isolated interior frost.

SYNOPSIS

Interior high pressure and a thermal low will maintain warm, dry conditions today. An approaching cold front introduces more extensive cloud cover and a chance for measurable rain to Del Norte and northern Humboldt counties late Thursday night into Friday. Colder temperatures will follow through the weekend.

DISCUSSION

Light coastal drizzle has accumulated up to a few hundredths of precipitation over the past two days, mainly around Humboldt Bay. This trend continues with drizzle is already being observed late Tuesday evening. Temperatures trend warmer today with a strengthening thermal trough. Low to some mid 90s are forecast for the warmer interior valleys today before a shortwave trough begins moving in later this week. There will be a compact surface low with the trough that has the potential to bring some stronger southerly winds, especially if the track nudges south at all. NBM has moderate to high chances for gusts over 30 mph for the coastal headlands and interior ridges of northern Humboldt through Del Norte. There looks to also be a period of gusty winds in Lake County Friday.

Chances for rainfall increase late Thursday with the trough and cold front. The bulk of the shortwave energy looks to likely remain north over southern Oregon, with trailing showers and some light rain for mainly northern Humboldt through Del Norte. If the system tracks farther south, than some higher rainfall amounts will be possible, especially with the associated instability. There are currently moderate to high chances for the light rainfall to generally occur. Chances for over a half inch of rain are over 50% in much of interior Del Norte and around 20 to 30% in Humboldt County north of Eureka.

Cooler temperatures arrive Saturday morning behind the cold front passage. There will be opportunity for isolated interior frost in the colder valleys through the weekend and likely into early next week. Another trough is forecast through the weekend however, and the resulting cloud cover may prevent overnight lows from getting too cold. The broader pattern will favor either zonal flow or additional troughs next week, bringing the potential for more at least light rainfall mid to late next week.

AVIATION...(6Z TAFs)

IFR ceilings are being observed at both coastal terminals. These are likely to continue overnight with LIFR conditions possible around sunrise. Drizzle has also brought brief visibility reductions. Stratus is likely to lift and scatter after sunrise and will likely be scattered out by noon. Interior areas, outside the near-coast river valleys, are likely to remain VFR for the next 24 hours. Stratus is likely to return to the coastal terminals this evening.

MARINE

Strong northerly winds continue across the outer waters and in the lee of Cape Mendocino. The Gale Warning for the southern outer waters has expired, however, localized gale force winds are still possible within the lee through the evening. Nearshore winds outside of the Cape and Pt. St. George will be much lighter peaking at around 10 to 20 kts. Seas will ease nearshore as a mid period NW swell subsides and wind waves also begin to subside.

Winds weaken late today into Thursday as a trough passes through the area. There will be an area of gale strength winds within a core of an area of low pressure. This may impact the northern waters as it passes. The northerlies will quickly restrengthen behind the trough Friday and through the weekend.

EKA WATCHES/WARNINGS/ADVISORIES

CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 9 PM PDT this evening for PZZ455.

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

Small Craft Advisory until 3 AM PDT Thursday for PZZ475.