textproduct: Eureka

SYNOPSIS

Near to slightly below normal temperatures today with clearing skies. Chilly temperatures likely again tonight. Rain likely returns by Wednesday. Near freezing or freezing low temperatures are expected late in the week with more rain possible over the weekend.

DISCUSSION

The low pressure is moving out of the area and high pressure has started to build in. Models have backed off the rain on Monday morning and now just a trace to a few hundredths are expected in Del Norte County and coastal Humboldt. Clear skies are generally expected, although it looks like some of higher terrain in the north may see lingering clouds. Tuesday morning there is the potential for more frost. It looks more likely than Monday morning with less clouds expected in Mendocino and Lake counties. Tuesday afternoon temperatures are expected to be a few degrees warmer than Monday, but remain in the 50s at the coast and the 60s inland.

Tuesday night and Wednesday and upper low moving into Washington is expected drag a front across northern CA and bring some rain. This is mainly expected to impact Del Norte and Humboldt counties. Rainfall amounts have continued to trend upwards in the models for this storm. The current NBM is showing rainfall amounts around an inch for Crescent City and Del Norte, but rapidly diminish as the front moves south and weakens. Around a half inch is expected in Eureka, a quarter inch in Weaverville and northern Mendocino county. Less than a tenth of an inch is expected in southern Mendocino and Lake counties. As usual the mountains will see more than the valleys. Snow levels are expected to be over 5,000 feet for most of the precip, but may drop below 4,000 feet as the precip comes to an end Wednesday evening.

Wednesday night into Thursday morning has the potential to be an unseasonably cold morning. The NBM is showing lows in the 20s in northern Lake, northeast Mendocino, and much of Trinity county. While this is certainly possible, fog and low clouds may develop in some of the valleys to limit the radiational cooling. Thursday afternoon clear skies and dry conditions are expected with highs warming back into the 60s. This will likely set up Thursday night to be the coldest night with lows in the upper 20s to upper 30s across the area. Even the coast may see frost with some weak offshore flow. Friday and Saturday afternoon highs are expected to warm into the 70s and Saturday morning will likely not be as cold as Friday morning.

Saturday night through Monday more rain is expected. At this point the probability of over a half inch is less than a 35 percent for any particular 24 hour period. However much of the area has a 20 to 50 percent chance of exceeding a half inch in 72 hours.

AVIATION...(06Z TAFs)

Mostly VFR conditions expected after the last few days of intense weather. The cache of moisture on the ground would normally raise concerns for ground fog development but conditions do not look favorable for reduced visibility from radiational cooling as clouds linger and some easterly flow is being picked up by the models. Ceilings are likely to come down to around 1500 to 2500 feet at KACV and KCEC overnight but not bellow MVFR thresholds. Northerly winds will build Tuesday afternoon, just below 20 knots. /EYS

MARINE

Unsettled weather marks the post low conditions over near coastal and offshore area waters. After the passage of the low, high pressure will fill in by Monday late morning as northerlies build with 10 to 15 kt sustained winds and gusts up to 20 kts or more. Monday evening northerlies will further build to around 20 kt sustained with 30kt gusts, particularly south of Cape Mendocino. Tuesday, winds diminish in the northern outer waters while shifting to a southerly bearing. Southern waters Tuesday will have a NW bearing at a higher rate, especially in the coastal waters in the lee of Cape Mendocino. Winds strengthen to fresh breezes Tuesday night into Wednesday as a cold front approaches from the North. This will be followed by strengthening northerly winds Wednesday night through Friday as the pressure gradient tightens. There is a high potential (85-100% probability) of gale force gusts Thursday-Friday. /ZVS /EYS

EKA WATCHES/WARNINGS/ADVISORIES

CA... Winter Weather Advisory until 11 PM PDT this evening for CAZ107.

Frost Advisory from 2 AM to 8 AM PDT Monday for CAZ110-111- 114-115.

NORTHWEST CALIFORNIA COASTAL WATERS... None.