textproduct: Eureka

KEY MESSAGES

* Unseasonably hot temperatures will build through the end of the week, peaking around Saturday. Such temperatures will generate Moderate HeatRisk across the interior.

* Shallow, diurnal marine layer persisting along the coast through the weekend.

* Nearly 0% chance of wetting rain for the next 10 days.

SYNOPSIS

High pressure building into the weekend will bring unseasonably hot and dry conditions to the interior. Morning fog will be most likely along the coast with quick clearing into the afternoon. Winds will generally be light.

DISCUSSION

Unusually strong high pressure will build across the area today and persist through the weekend. For the interior, this will mean hot and dry conditions with weak terrain winds. Saturday will most likely be the hottest day with some interior locations likely to approach 100. Such temperatures are unusual for October. AT KUKI, for example, NBM has a 50% chance of temperatures hitting 101, which would ties the all time high for the day. Along with this, Moderate HeatRisk will cover most of the interior with isolated high Heat Risk in southern Mendocino and Lake Counties. Longer and cooler nights will generally prevent Heat Risk from climber higher. Closer to shore, a stronger marine inversion will promote a shallow but resilient marine layer aided by weak onshore flow.

Looking further ahead, high pressure will very slowly weaken early next week, though above average interior temperatures will most likely linger until mid week. Most models show a weak cutoff low impacting the area. At most, this low will lift the marine layer and promote some drizzle. Just a few ensemble members (5%) indicate it may produce very weak interior thunderstorms around Monday afternoon. Other than weakening high pressure, there is no impactful weather on the horizon. There remains a near zero chance of wetting precipitation for at least the next 10 days. Long Range forecast suggest this dry pattern is most likely to persist through at least the second week of October. /JHW

AVIATION...06z TAF

Under the influence of building high pressure and weak onshore flow, LIFR ceilings and visibilities have again formed right along the coast overnight. As of 06z, clouds have been mostly restricted to Humboldt Bay, but high resolution models suggest (65% chance) clouds will push north to Crescent City by Sunrise. Marine clouds will most likely (80% chance) clear to VFR by mid morning Thursday. Otherwise, stagnate VFR conditions will persist throughout the interior. /JHW

MARINE

Near gale force gusts have pushed away from shore and into the outer waters Wednesday evening. These winds will gradually weaken with more moderate to strong wind gusts during the day on Thursday. Winds will remain remarkably calmer closer to shore. Steep short period seas over 10 feet will remain in the outer waters with some steeper seas around 7 feet at 9 seconds pushing into the inner waters. Beyond short period seas, a very minor southwest swell is augmenting the sea state. Winds will weaken through the weekend as high pressure pushes east of the area. Outer water gusts will most likely drop below 21 kts by Saturday afternoon with seas also dropping below 5 feet. These more subdued conditions will likely persist into early next week. /JHW

FIRE WEATHER

Hotter and drier weather building through the weekend will increase fire danger. Near record high temperatures for October will aid in ERC values cresting back near the 90th percentile early next week. That said, very weak terrain winds and increasingly long nights will prevent Burning Index values from reaching above the 70th percentile. These values imply fire may be unusually easy to ignite but spread potential is only moderate. There is little chance of weather induced ignitions with only a very minimal (<5%) chance of weak and isolated interior thunderstorms late this weekend. /JHW

EKA WATCHES/WARNINGS/ADVISORIES

CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 9 AM PDT this morning for PZZ450- 455.

Gale Warning until 9 AM PDT this morning for PZZ470-475.