textproduct: Eureka

SYNOPSIS

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

DISCUSSION

Unusually strong high pressure continues to build into the area Friday. Interior highs have jumped into the mid and upper 90s. In the coming days, hot and dry conditions with weak terrain winds will persist. Saturday will most likely be the hottest day with some interior locations likely to reach 100. Such temperatures are unusual for October. AT KUKI, for example, NBM has a 50% chance of temperatures hitting 101, which would tie 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. High temperatures alongside warm lows overnight have justified a localized Heat Advisory for Saturday. Longer and cooler nights will generally prevent Heat Risk from climber higher further north. 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 next week, though above average interior temperatures will most likely linger until around Wednesday. Most models show a weak cutoff low impacting the area around Monday. At most, this low will lift the marine layer and promote some drizzle. There is mixed confidence, but about 50% of models show another peak of highs near 100 on Tuesday behind the low. 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

MARINE

Moderate to strong winds wind have persisted in the outer waters with much calmer winds 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 bleeding 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. Enhanced conditions will persist through next week. /JHW

EKA WATCHES/WARNINGS/ADVISORIES

CA... Heat Advisory from 11 AM to 11 PM PDT Saturday for CAZ112- 113-118>120.

NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 9 AM PDT Saturday for PZZ470-475.