Area Forecast Discussion
Issued by NWS Eureka, CA
-- Highlight Changed Discussion --
Issued by NWS Eureka, CA
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --526 FXUS66 KEKA 261123 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 423 AM PDT Sun May 26 2024 .SYNOPSIS...-- Changed Discussion --Mostly clear skies and dry conditions are expected today once some morning low clouds in Humboldt county lift. Highs are expected to be around 80 in the interior today warming into the low 80s Monday. Cooler temperatures and coastal fog and drizzle are expected Tuesday. A warming trend is expected Thursday through Saturday.-- End Changed Discussion --&& .DISCUSSION...-- Changed Discussion --Weak high pressure is over the area bringing mainly clear skies and dry conditions to the area. Warmer temperatures are expected this afternoon. Coastal and valley clouds and fog are limited to mainly Humboldt county this morning morning thanks to a weak inversion and offshore flow. Breezy conditions are expected along the coast once again this afternoon with northwest winds of 10 to 15 mph. Most areas are expected to see clearing today, but it may take some time for the stratus to clear at the coast. Monday there is an upper level trough moving into the Pacific Northwest and this will be felt in Northwest California. Monday afternoon there is a small chance for showers and possible a thunderstorm in northern Trinity county. There is some instability, but with the poor lapse rates in the mid levels it looks like there might not be any thunder. Also, only the SREF thunder probabilities are showing more than 5 percent. So for now have just added a slight chance of showers for northeastern Trinity county. This approaching trough is expected to shift the wind field to more onshore and stratus is expected to return on Monday. Monday night and Tuesday this is expected to continue to deepen the marine layer and drizzle is likely along the coast. Tuesday is expected to see cooler temperatures with highs dropping back into the 70s. The coast may stay in the 50s with the expected marine layer lingering through at least midday. Wednesday the trough starts to pull out of the area but coastal clouds may be slow to clear out and the interior will continue to see highs in the 70s. This is a couple degrees below normal. Thursday through Saturday night pressure starts to build into the area and inland areas will see warmer temperatures. The mid 80s are expected Thursday. Friday looks to be the warmest day with highs in the upper 80s to around 90. The NBM shows a 50 to 75 percent chance of high temperatures exceeding 90 degrees in the valleys. The ensemble clusters still show uncertainty on this warmup. Friday a couple of the clusters show the trough lingering over the Great Basin longer and keeping temperatures cooler. Saturday the models are in better agreement in the start of a cooling trend as another trough moves towards the area. MKK-- End Changed Discussion --&& .AVIATION...-- Changed Discussion --12Z TAF ACV/CEC...Stratus formed along the coast after midnight and began expanding into ACV and up the coast toward CEC in a southerly component of a coastal wind eddy. Light offshore surface winds are keeping full inundation to the coast so far. Model soundings lower CIGs through sunrise to LIFR levels as the stratus fills in, and patchy fog may develop. With a building ridge and increasing 850 mb temperatures, the McKinleyville profiler is beginning to show the signature of a strengthening low level inversion. This may hinder but not fully inhibit typical scattering of the stratus, particularly around Humboldt Bay. Surface moisture and moisture pooling will increase tonight as subtle influence from an approaching late season Pacific trough takes effect. This will increase chances for LIFR CIGs and VIS towards the end of this 12Z TAF period, as well as potential good coverage of early morning fog at the coastal terminals. UKI....With a shallower marine layer, the threat for spillover from the west is gone. Winds will also be light and mostly variable. A few W to WNW afternoon gusts may occur. VFR conditions are expected to prevail with no clear signature for southerly flow and stratus transport.-- End Changed Discussion --&& .MARINE...-- Changed Discussion --A weak northerly wind pattern persists. Winds continue to be accelerated south of Cape Mendocino where gusts up to 32 kts and short period seas of 6 to 8 feet create Small Craft Advisory conditions. The steepened seas in the northern waters will drop to 5 ft or less today as winds drop to 15 kt or less. Expect very similar conditions to carry into next week. Coverage of Advisory winds in the southern zones will become more narrowly confined south of the cape, but coverage justified extension of the Advisory. A mid period NW swell at around 5 ft at 13 seconds from a late season Pacific trough of low pressure will also arrive on Tuesday. Building high pressure mid to late next week will increase northerly winds in all zones. There is growing probability for gale conditions through that period.-- End Changed Discussion --&& .EKA WATCHES/WARNINGS/ADVISORIES...-- Changed Discussion --CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 9 AM PDT this morning for PZZ455- 470. Small Craft Advisory until 11 PM PDT this evening for PZZ475.-- 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