Area Forecast Discussion
Issued by NWS Eureka, CA
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Issued by NWS Eureka, CA
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-- Discussion containing changed information from previous version are highlighted. --457 FXUS66 KEKA 282156 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 256 PM PDT Tue May 28 2024 .SYNOPSIS...-- Changed Discussion --A warming trend will kick off this week with the hottest inland valleys reaching the upper 90s late this week. A regular cycle of stratus and gusty afternoon onshore flow will persist for the coast.-- End Changed Discussion --&& .DISCUSSION...-- Changed Discussion --An upper level trough is evident passing by NW California this afternoon, allowing for all morning stratus to easily clear out from a weakened marine inversion. High resolution models hint at the lift causing some isolated coastal drizzle tonight, but even the most aggressive models show nothing more than trace accumulation. Otherwise, the trough has had little impact beyond some enhance fair weather cumulus over interior mountains. All models show high pressure building in through Friday. This will bring hot temperatures back to the interior with NBM even showing a 25% chance of 100 degree highs in the very hottest valleys in Trinity County on Friday. Combined with dry air behind the trough, such conditions will continue to dry fuels through the weekend. Building high pressure will also support a usual cycle of nighttime marine stratus with gusty north winds pushing on shore and helping to mix out clouds each afternoon. Onshore winds will mostly likely be strongest on Thursday with peak afternoon gusts around 30 mph. Cluster ensemble members show another series of troughs digging across the Pacific Northwest late in the weekend through early next week. Though any impacts are sure to minor, the exact depth of the troughs remains highly unlikely leading to two main possible scenarios. 30% of models favor a weaker trough with high pressure sneaking over the area. This would allow for another warm period with interior temperatures back into the 90s. About 70% of models show stronger influence form the trough with NBM which would bring cooler and more moist weather, especially to the coast. NBM is even showing a 20% chance of wetting rain along the Del Norte Coast next Monday. The very highest end models show light rain of up to 0.3 inches. A most likely scenario will come into better focus as models continue to evolve. /JHW-- End Changed Discussion --&& .AVIATION...-- Changed Discussion --A narrow band of stratus stretched over the North Coast from Cape Mendocino to the Oregon border this morning; Over Humboldt, Cigs were generally low MVFR...including ACV; but over Del Norte, Cigs were mostly IFR...including CEC. Conditions became VFR before noonday as a weak disturbance contributed to the scouring of clouds. NW-N winds have increased today for somewhat gusty winds at ACV and UKI. Above ground winds will increase south of Trinidad (Humboldt Coast) and along the Mendocino Coast through evening. Although minimal, there is a chance for LLWS over ACV this evening. MVFR/IFR clouds are expected to return to the Coastal TAF sites overnight. The clouds are expected to mix out by late Wednesday morning. /TA-- End Changed Discussion --&& .MARINE...-- Changed Discussion --Moderate northerly flow will continue as the axis of an upper trough traverses the PNW and far northern CA. While wind gusts in the southern waters meet small craft criteria, wave heights will hover around 5-7 feet under the influence of a decaying long period NW swell. An offshore ridge building into the region will tighten the inland thermal trough gradient and enhance offshore winds Wednesday afternoon into Thursday. Gale conditions expected to build on already enhanced conditions in the southern waters before expanding north early Thursday. Rapid wind wave response expected Thursday afternoon into Friday, with wave heights forecasted to exceed 12 feet at 10 seconds by early Friday. Long range models are beginning to agree on a progressive trough pattern developing this weekend, effectively inhibiting the expansion fans downwind of Port Orford and Cape Mendocino. Seas expected to follow suit as a nearshore westerly swell traverses the waters.-- End Changed Discussion --&& .EKA WATCHES/WARNINGS/ADVISORIES...-- Changed Discussion --CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory from 3 PM Wednesday to 9 PM PDT Thursday for PZZ450. Small Craft Advisory until 3 PM PDT Wednesday for PZZ455- 475. Gale Watch from Wednesday afternoon through Thursday evening for PZZ455-475. Gale Watch from Wednesday evening through Thursday evening for PZZ470.-- End Changed Discussion --&& $$ 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