231 FXUS66 KEKA 081140 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 440 AM PDT Fri Oct 8 2021 .SYNOPSIS...Cool and mainly dry weather will occur across the region today. A warming trend will then take place this weekend, followed by the passage of a strong cold front Sunday night, which will give way to cool and breezy weather early next week. && .DISCUSSION...Pictures from space this morning showing very little high cloud cover over the cwa. A Frost Advisory remains in effect for inland areas and despite the absence of clouds only a few localized spots are showing frost type temperatures. As of 4am most areas are in the upper 30s to lower 40s. Another challenging forecast for possible frost again tonight across the interior zones as cool dry flow begins to filter across the region with the approach of another inside slider type trough. This feature is expected to provide clouds and some light shower activity to portions of the coastal areas and perhaps around southern Mendocino and as far south as the Bay Area. Given the expected cloud cover...frost may not be an issue except for the far eastern interior valleys. A secondary front associated with the passage of a potent shortwave trough will then pass through Monday morning, with significantly colder air to follow. This will set the attention toward fire concerns as brisk northerly and north- northeast winds will begin to ramp up Sunday night into Monday morning...especially across Mendocino and Lake Counties. See Fire Weather discussion below. General north and northwest flow aloft across the region will continue into next week promoting chilly mornings and mild afternoons. Interior valleys will see threats of frost each night and morning in the absence of any cloud cover. && .AVIATION...Marine stratus blankets much of the North Coast this morning, though conditions have generally remained in the MVFR to VFR range. Guidance suggests these low clouds will burn off by midday and likely give way to VFR conditions this afternoon along much of the coast. Though, haze at KCEC will probably keep conditions in the MVFR range this afternoon. HREF does indicate a probability of 30 to 40 percent for some low clouds to impact KUKI later this morning, but confidence is not very high in this playing out. && .MARINE...Northerlies will continue to weaken throughout the day today and then hover generally around gentle to moderate breezes over all zones as we head into the weekend. Winds will ramp back up starting early on Sunday and peak over portions of the southern waters as near gales early on Monday. Winds are forecast to stay around fresh to strong breezes in the northern outer waters and to near gales in portions of the southern outer waters through early Tuesday. Otherwise, several northwest swells will impact the coastal waters during the next few days. && .FIRE WEATHER...A Fire Weather Watch remains in effect for fire weather zones 277 and 264. At this time strongest winds look to be focused over SE Lake County on Monday through Tuesday morning at elevations around 2500 ft. Forecast models show north and northeast winds reaching 30 to 40 mph during this time frame for that area which will also coincide with very low RH. Confidence is tempered at this time because the forecast model often overdoes the wind speeds 4-5 days out and will lower as the event draws closer. Once the higher resolution model data begins to come in (Sat-Sun) confidence and specifics will increase. Nonetheless it does look like a potentially strong northerly wind event and given the state of dryness with regard to fuels a Fire Weather Watch is warranted. As opposed to some of our stronger and more critical Autumn easterly flow events, during this period winds will be more out of the north and north-northeast than east, which will tend to keep the drier air and stronger winds focused along the eastern edge of our area, and more into the Sacramento Valley and East Bay hills. Winds will ease later Tuesday through mid-week, and the airmass will gradually modify. && .EKA WATCHES/WARNINGS/ADVISORIES... CA... Frost Advisory until 9 AM PDT this morning for CAZ106>108- 110-111-114. Fire Weather Watch from Monday morning through Tuesday afternoon for CAZ264-277. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 9 AM PDT this morning for PZZ450- 455-470-475. && $$ 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