textproduct: Eureka

KEY MESSAGES

- Temperatures will warm quickly with moderate to major HeatRisk expected Thursday through the weekend and into early next week.

- Elevated fire weather conditions in Lake County with low afternoon relative humidity and gusty winds Wednesday through Thursday.

- Breezy winds are expected along the coast again Thursday afternoon.

SYNOPSIS

Temperatures are expected to warm to the upper 90s to around 100 in interior valley locations by Thursday through the weekend. Breezy winds are expected along the coast during the afternoon and evening through again Thursday. High temperatures in the upper 60s to around 70 degrees can be expected along the coast, warmest possibly this weekend.

DISCUSSION

High pressure and offshore is bringing clear skies to much of the area. Some clouds developed in the river valleys this morning along the coast. Tonight mostly clear skies are expected across the area with the offshore flow. A few clouds are possible around the Eel River Delta and other areas near the coast in the river valleys. Breezy north to northeast winds are expected over the higher terrain tonight, especially in the Yolla Bolla mountains and down into eastern Lake county. This higher terrain is expected to see winds of 15 to 30 mph with gusts to 40 mph in the favored locations of eastern Lake county. This will elevate fire weather concerns, see the fire discussion for details. Temperatures tonight in most areas are expected to warmer than this morning, generally in the upper 40s to low 50s. Thursday afternoon high temperatures in many areas are expected to be nearly 10 degrees warmer than today. Some of the warmer valleys will be approaching 100. This may be the hottest day for some of the near coastal valleys such as Gasquet, Garberville, and Boonville. At the immediate coast temperatures may reach the mid to upper 60s, but the breezy northerly winds off the water in the afternoon will likely keep them from getting much warmer. Thursday night into Friday morning temperatures are generally expected to be in the 50s in the valleys with temperatures remaining near 70 on some of the ridges. The heat advisory remains on track in southern Mendocino and Lake counties. Friday afternoon the marine layer may start to influence western portions of Mendocino county keeping temperatures slightly cooler.

Saturday a weak shortwave moves down from the north and this may slow the warming or keep some areas slightly cooler. This could potentially spark off some thunderstorms, but at this point it looks like it will be too dry aloft and the threat will be well to the east of us. Monday and Tuesday the heat continues to build and more heat advisories or even a warning may be needed for this area. This currently looks like they will be the hottest days. Wednesday now looks like it might be the start of the cooling trend. MKK

AVIATION

High pressure is building in bringing clear skies to the area and gusty winds. These winds will diminish at the coast and in the valleys tonight, but remain breezy over the ridges. Most areas areas are expected to remain clear tonight, although it is hard to rule out a few clouds around Humboldt Bay or the Eel River Delta and possibly the near coastal river valleys. Thursday afternoon is expected to see widespread sunshine again with more breezy winds, mainly along the coast. MKK

MARINE

Northerly winds are increasing to near gale and gale this afternoon and evening. The waves will become dominated by the steep short period waves, but currently there is still an 18 second southerly wave there is 3 to 4 feet and a northwest swell 5 feet at 10 seconds. Tonight the winds will diminish slightly near the coast only to increase again on Thursday near the coast.

Friday wind the strongest winds are expected to start pushing farther off the coast south of Cape Mendocino. So have extended the gale warnings, but only through Thursday night for the southern outer waters. The stronger winds are expected to linger in the northern outer waters through Friday night and possibly longer. Currently it looks like the gales will continue beyond 10 to 20 nm north of Cape Mendocino on Saturday, then start to diminish on Sunday and this allows a southerly surge to move northward. Winds are generally expected to remain lighter into early next week. MKK

Fire Weather

Temperatures are expected to continue to warm Thursday with near 10 degrees warmer again. Along with the warming temperatures, very dry air is expected to move in and this will lower RH each day. The ridges are expected to see poor RH recoveries by Thursday morning. This will combine with some northerly winds over many of the higher ridges. The strongest winds are expected to be in the Yolla Bolla's and down into the higher terrain of eastern and southern Lake County. The red flag warning remains on track for tonight. Fuels are likely still marginal, but winds of 15 to 30 mph and RH expected to increase only to 20 to 40 percent is concerning enough to highlight the threat with a red flag product. Thursday afternoon RH is expected to drop into the low teens in much of the interior valleys. The winds are expected to diminish by the afternoon, however they may remain strong in eastern Lake county so have extended the red flag warning into the afternoon for zone 419. MKK

EKA WATCHES/WARNINGS/ADVISORIES

CA... Heat Advisory from noon Thursday to 10 PM PDT Friday for CAZ113-114-118>120.

Red Flag Warning from 11 PM this evening to 9 AM PDT Thursday for CAZ420.

Red Flag Warning from 11 PM this evening to 5 PM PDT Thursday for CAZ419.

NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory from 2 PM this afternoon to noon PDT Thursday for PZZ450.

Small Craft Advisory until 2 PM PDT this afternoon for PZZ455.

Gale Warning from 2 PM this afternoon to 3 AM PDT Thursday for PZZ455.

Small Craft Advisory until 9 PM PDT this evening for PZZ470.

Gale Warning from 9 PM this evening to 3 AM PDT Saturday for PZZ470.

Small Craft Advisory until 10 AM PDT this morning for PZZ475.

Gale Warning until 3 AM PDT Friday for PZZ475.