textproduct: Eureka

KEY MESSAGES

* Very dry conditions with gusty northeast winds focused in Lake County will increase fire danger Thursday and Friday.

* A warming trend peaking Thursday and Friday with interior highs in the 90s.

* Cold front most likely to cross the area Sunday into Monday. 50% chance of wetting rain along the North Coast.

SYNOPSIS

A general warming trend will peak today and Friday, even for the coast where marine influence remains weak. Cooler and more moist conditions build by the weekend.

DISCUSSION

Weak high pressure continues to build across the area. Interior high temperatures will peak Thursday and Friday with highs in the 90s, which is much warmer than normal for mid October. Meanwhile, a positively titled trough passing across central California will promote moderate to strong northeast winds, especially for the southern half of the area. Gusts will generally remain less than 25 mph, but they will pull in very dry air keeping even the coast mostly free of marine influence. Winds will weaken again Friday, likely (50% chance) allow a weak marine layer to finally form near shore.

High pressure will break down this weekend. Winds turning back onshore will help push in a deeper and stronger marine layer with interior highs pulling back into the 70s. A cold front will cross the area around Monday, but potential moisture with the front remains uncertain. Wetting rain potential along the North Coast has decreased back to about 30% with most likely rainfall of 0.1 to 0.15 inches. Winds with the front appear only moderate at best even in high end models. Regardless of rainfall, there is high confidence in generally seasonable cool and moist conditions through next week with another front likely around next Wednesday. /JHW

MARINE

Northerlies continue to reduce in area, exposing lighter winds over the inner and most of the outer waters. Seas reducing from 8ft to around 5-6ft by Thursday afternoon with 4-5ft seas in the inner waters. An upper mid period swell continues from the northwest at 4ft-13sec and a westerly swell at 2ft-16sec, through Thursday afternoon and diminishing a few days after. The sea state will be mixed with a return of near gale northerlies late in the weekend. /EYS

FIRE WEATHER

A warming and drying trend will peak Thursday and Friday. Interior highs will reach near 90 with RH sticking in the the teens. ERC values will return close to the 80th percentile, representing moderate to high fire danger. Said percentiles are near record breaking for the time of year but remain much lower than peak summer.

Beyond just warm and dry conditions, a very positively tilted trough over the central California Coast will promote moderate northeast winds today, mostly restricted to high ridges as far north as central Humboldt County. Winds will be locally strong in southern and eastern Lake County with gusts mixing in the afternoon over 25 mph. These winds will promote areas of critical fire weather with a Red Flag warning in effect. Northeast winds will weaken Friday, but remain gusty along high ridges at least through the morning. Conditions will be exceptionally dry Friday in the wake of the winds with many interior locations seeing single digit RH. /JHW

EKA WATCHES/WARNINGS/ADVISORIES

CA... Red Flag Warning until 2 PM PDT this afternoon for CAZ418- 419.

Fire Weather Watch from late tonight through Friday afternoon for CAZ418-419.

NORTHWEST CALIFORNIA COASTAL WATERS... None.