933 FXUS66 KEKA 071251 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 451 AM PST Sun Nov 7 2021 .SYNOPSIS...Clear, drier, and warmer weather is expected today and early Monday. Another front is expected to move in Monday afternoon and evening. This will bring strong winds along the coast along with widespread moderate rain and snow to high elevation areas. Clearer and warmer weather is expected later in the week. && .DISCUSSION...Some scattered showers continue to linger across the area early this morning. Fog has formed in many interior valleys with many getting cold enough for patchy frost. Showers should tapper off today with mostly clear skies and seasonable temperatures expected. Valley fog and some patchy frost can be expected again Monday morning. Models today have put in a bit more cloud cover, keeping overnight lows a bit higher. The freeze watch has been replaced with another frost advisory in response. A fast moving trough aloft is expected to push a strong low pressure system into the Pacific Northwest on Monday. This system will drag a well defined cold front into area Monday afternoon and evening. Winds with this front appear considerable with the GFS and NAM showing 925 mb winds around 50 kts near the coast. NBM 4.1 shows winds on near shore ridges just grazing near 40 kts. Valleys are more protected, but the models still places winds of 30 kts in Eureka and Crescent City. Models today have better agreement on the development of the low. Wind look to start picking up Monday afternoon and die down by midnight. A wind advisory has been issued for all coastal zones and for near shore ridges above 1500 ft. The low's further north track in models today dropped the NBM's probability of widespread winds above 35 kts below 10%. Rain is currently expected behind the front with around 1 to 2 inches expected throughout the area with higher amounts at higher elevations. Amounts look much lower around Humboldt Bay thanks to downsloping winds off the King Range. Moderate snow is expected for the higher elevations of Trinity county. Models currently put 14 to 18 inches along the peaks of the Trinity Alps. Scott Summit could see 8 to 10 inches and Buckhorn Summit could see 2 to 4 inches. NBM and NAM showed higher snow levels today. Upslope winds and high precipitation amounts however still seem on track. This may lower snow levels below current model estimates early in the event. This possibility is actually reflected in NBM and WPC snowfall guidance which puts snow below the NBM snow levels. As such, snow level grids have largely been retained from previous forecasts. The winter storm watch above 3000 ft has been upgraded to a warning in northern Trinity and winter advisories have been added for southern Trinity to cover light snow along highway 36 early in the event. Later in the week, rain will slowly taper off, though a deep marine layer may allow drizzle to persist north of Cape Mendocino through Wednesday. Model clusters are currently in remarkable agreement that at least moderate ridging will settle in late next week into next weekend. This will bring a respite to winter rain. Sunny and mild conditions could be expected for the interior with calm, foggy conditions near the coast. /JHW && .AVIATION...Rain showers will taper off in the coastal terminals by early Sunday morning, but there may still be some chance for rain at KCEC until Sunday evening. Winds at KCEC are projected to be around 10 to 15 knots, while KACV is looking at 5 to 10 knots. Winds at KUKI will be light and variable. Some low ceilings and fog may develop early this morning in Ukiah. The area as a whole will experience dryer conditions with VFR conditions by this afternoon before the next low pressure system moves in Monday evening. && .MARINE...Mainly southerly winds of 5 to 15 kt persist across the waters this morning. A northwest swell is also moving through the waters and currently it is around 9 feet at 12 seconds. These conditions are generally expected to persist through tonight in the proverbial "Calm before the storm". Monday an area of rapidly deepening low pressure starts to approach the coast and turn to the north well offshore. Current models show the low bottoming out at 971 mb as it moves into British Columbia. The frontal boundary associated with that low will bring strong winds to the northern CA waters. There are some models showing an area of low pressure forming along the front and this could help to increase winds. For now the models remain consistent in showing a period of storm force southerly winds at least over the outer waters Monday afternoon and evening. So have added storm warnings to the outer waters to highlight this. Closer to shore it looks like there will mainly be gale force winds with storm force gusts limited to areas near Cape Mendocino and Pt St George. Gale warnings are in place to highlight this. These winds will develop a short period waves, although the winds will be short lived so it is hard tell exactly how the waves will have time to get. The models show these ranging from 15 to 20 feet. Behind the front on Tuesday a northwest swell builds into the waters at around 10 feet and a southwest swell around 8 feet is also moving through the waters. Winds will generally be west to southwest around 10 to 15 kt Tuesday. Wednesday another northwest swell moves into the waters quickly building to around 12 to 14 feet at 16 seconds. Southerly winds of 5 to 15 kt continue in general, although they may start to turn northerly in the southern waters. Late in the week and into the weekend northerly winds will gradually return to all waters. Waves will diminish and will generally only be around 4 to 6 feet starting Thursday. MKK && .BEACH HAZARDS...The tidal surge/anomalies have diminished this morning and the astronomical tides will lower today than yesterday. Coastal flooding is now expected this morning. Monday strong southerly winds will likely bring a surge/anomalies again, however the winds don't really come up until after high tide and over a foot of surge would be needed to see flooding around Humboldt Bay. This will need to be watched as it gets closer. MKK && .EKA WATCHES/WARNINGS/ADVISORIES... CA... Wind Advisory from 2 PM to 10 PM PST Monday for CAZ101>106- 109-110. Winter Weather Advisory from 10 AM to 10 PM PST Monday for CAZ108. Winter Storm Warning from 10 AM Monday to 7 AM PST Tuesday for CAZ107. Frost Advisory until 8 AM PST this morning for CAZ106-110- 111-114. Frost Advisory from 2 AM to 8 AM PST Monday for CAZ106-110- 111-114. NORTHWEST CALIFORNIA COASTAL WATERS... Gale Warning from 2 PM Monday to 1 AM PST Tuesday for PZZ450-455. Storm Warning from noon Monday to 1 AM PST Tuesday for PZZ470-475. && $$ Visit us at https://www.weather.gov/eureka Follow us on Facebook and Twitter at: https://www.facebook.com/NWSEureka https://www.twitter.com/NWSEureka For forecast zone information see the forecast zone map online: https://www.weather.gov/images/eka/zonemap.png