Area Forecast Discussion
Issued by NWS Eureka, CA
Issued by NWS Eureka, CA
303 FXUS66 KEKA 222204 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 304 PM PDT Sat Jun 22 2024 .SYNOPSIS...Hot and dry weather is expected in the interior Sunday through Tuesday, followed by more moderate temperatures Wednesday and Thursday. Coastal areas will remain much cooler. && .DISCUSSION...Stratus almost completely eroded this afternoon. New stratus has already been forming offshore north of Cape Mendocino and will likely begin to advance onto the North Coast and into the coastal river valleys this evening. Marine layer will deepen later tonight with another NW influx of shallow moist air and possible coastal drizzle and fog tonight into Sunday morning. Surface pressure gradients tighten behind the front and breezier N-NW winds with gusts to around 25 mph are expected around Humboldt Bay. Coastal headlands may have stronger gusts to 40 mph, based on HREF probabilities greater 50%. Otherwise, it will remain hot in the interior valleys Sunday through Tuesday. Another trough in westerly flow will result in some cooling Wed and Thu. Also, gustier diurnally driven west to northwest winds are expected again in the interior with this trough Wed and Thu. Also, mid layer humidity with a nebulous disturbance aloft originating from the subtropics may bring a some high level humidity to the southern portion of the area on Tuesday; southern Mendo and Lake. Potential for dry thunderstorms remains quite low at the moment; 1 to 3% chance. PWAT anomalies (above 200%) are forecast to stay well to the south of the area as an upstream trough keeps the forecast area in relatively dry westerly and southwesterly flow aloft. NBM remains consistent with high temperatures "cooling" below normal on Thu as a 500mb trough moves across the Pacific NW. NBM probabilities for rain Wed through Thu are not zero, but no more than 10% for Del Norte and northern Humboldt. Some coastal drizzle and a few hundredth`s are not completely impossible as a decaying front generates a shallow push of moisture. Chance for a tenth or more is near zero. A warming trend for the interior will most likely commence next Friday with above normal temperatures returning next weekend. DB && .AVIATION...LIFR stratus blanketed the coast this morning through the early afternoon. Sun was finally able to breakthrough today, however, bringing VFR conditions along most of the coast this afternoon. Such clearing is destined to be short lived, however. Inconsistent IFR ceilings and visibilities will most likely start to return early this evening with NBM and HREF showing a 90% chance of LIFR ceilings around Humboldt Bay by 9PM. Brief clearing is again possible tomorrow afternoon (30% chance) though increasing high pressure and inversion strength will make the chances lower than today. Otherwise, widespread VFR conditions will persist for the interior with normal summer conditions. /JHW && .MARINE...Northerly winds have generally decreased today with moderate gusts above 21 kts only persisting in the outer waters and around Cape Mendocino. Short period seas have followed suit with the northern waters dropping below 6 feet tonight. Calmer conditions will be short lived, however, with a northerly push ramping wind back up Sunday. This will bring gusts and steep short period seas back throughout all waters, but especially in a fan south of Cape Mendocino where gale force gusts should be expected. Steep seas up to 10 feet will also fan south of the Cape and throughout the southern outer waters. Northerly winds will again ease off early this week with generally moderate gusts by Monday evening. By that point, only the southern waters will most likely support short period seas steep enough for a small craft advisory. Besides wind waves, a minor northwest swell of 5 feet at 11 seconds will augment the sea state starting early Monday morning, likely slightly delaying the general calming trend in the overall sea state, especially in the northern waters. /JHW && .EKA WATCHES/WARNINGS/ADVISORIES... CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory from 3 PM Sunday to 3 PM PDT Monday for PZZ450. Small Craft Advisory until 3 PM PDT Monday for PZZ455-475. Small Craft Advisory until 6 PM PDT this evening for PZZ470. Small Craft Advisory from 9 AM Sunday to 3 PM PDT Monday for PZZ470. && $$ 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