textproduct: Eureka

SYNOPSIS

Light rain is expected to come to an end Saturday morning. Unseasonably cool temperatures are expected across the area with Saturday expected to be the coolest day. Moderate to strong winds are expected across the area Saturday. A gradual warming trend is expected into early next week.

DISCUSSION

A weak front is bringing some light rain to Del Norte county with occasional light rain showers farther south and east. These rain showers are not expected to expand much more and are expected come to an end Saturday morning. The upper level trough associated with the front is expected to bring temperatures below seasonal normals for the interior with highs only in the upper 60s to 70s in the valleys. Also, behind the front northerly winds are expected to increase Friday night and through Saturday across the area. Friday night the strongest winds are expected to be on the eastern Ridges of Lake and Mendocino counties. Saturday these stronger winds spread across much of the area. These winds will make for an unseasonably cool day across the interior feel even cooler. Some of the higher terrain in the Trinity Alps may see temperatures stay in the low 50s. Saturday night into Sunday morning will be the coldest night in a while. Frost is possible in the coldest spots of Humboldt county with areas dropping into the 30s. At this point frost is not expected, but there is a small chance it could happen.

Sunday high pressure starts to build into the area and temperatures across the interior start to warm up again. The warmup is expected to be gradual with highs Sunday expected to be in the upper 70s to near 80. Breezy north winds will continue, although they will mainly be in the afternoon and along the coast and coastal ridges. The warming trend is expected to continue through the middle of next week before leveling off. The highs are expected to generally be in the 80s through much of the week in the interior. The coast is expected to see some sun early in the week, but the marine clouds are expected to return at some point. MKK

AVIATION

A weak front is bringing light rain and drizzle to the Humboldt and Del Norte coasts this afternoon. This is creating IFR to LIFR conditions this afternoon. Late this afternoon and evening some lower clouds may bring some lower clouds to KUKI, however there is only a 40 percent chance of MVFR conditions. The front is expected to move through this evening and this should start to lift the ceilings on the north coast. Confidence is low on the timing of this. However by 12z or 14Z clouds are expected to have lifted to MVFR or IFR conditions. By 18Z confidence is fairly high that we will IFR conditions at both KACV and KCEC. Saturday afternoon will start to see some breezy north winds of 10 to 20 kt. MKK

MARINE

A front is bringing some light southerly winds near the coast this afternoon. Tonight behind the front winds are expected to become northerly and gradually start to increase. In addition the wind waves there are two small swells. One is around 2 feet at 15 seconds out of the south and the other is around 3 feet at 7 seconds. These are expected to continue for the next few days. Saturday afternoon and evening the winds start to strengthen more notably and small craft advisories may be needed in the southern waters initially. These winds are expected to strengthen on Sunday and the southern waters may see near gale or gale force winds by the afternoon. Stronger winds are expected to continue on Monday through Wednesday with near gale or gale force winds. Late in the week winds are expected to start to diminish again. MKK

FIRE WEATHER

A major pattern shift is underway this afternoon as a strong cold front pushes through the region. While this system brings critical wind speeds to parts of the interior, the fire weather threat is significantly mitigated by a substantial influx of moisture and high relative humidity values. Much of Northern Humboldt and Del Norte counties have see a tenth to a half inch of rain so far with some additional rain expected this evening. Drier interior zones to the south and east will miss out on meaningful wetting rain. The main operational focus centers on Friday evening and Saturday across the mountains of Lake, eastern Mendocino, and Trinity counties (including the Yolla Bollys). Strong westerly winds developing behind the front will sustain speeds of 10 to 20 mph, with ridge- top gusts frequently exceeding 30 to 40 mph. Fortunately, minimum relative humidity values on Saturday afternoon will remain high, primarily between 40 and 60% across the interior, and up to 80% along the coast. Exceptional humidity recoveries of 80 to 100% are forecast for Saturday morning, keeping fuel flammability low despite the high winds. Cooler temperatures are expected across the area on Saturday with highs in the low 70s in the warmer valleys. Localized destabilization will support a 10% chance of thunderstorms across northern Trinity County and interior Del Norte County on Saturday afternoon, though lightning coverage will be isolated. Warmer and drier conditions return Sunday as high pressure builds.

EKA WATCHES/WARNINGS/ADVISORIES

CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... None.