Area Forecast Discussion
Issued by NWS Eureka, CA
Issued by NWS Eureka, CA
620 FXUS66 KEKA 272206 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 306 PM PDT Mon May 27 2024 .SYNOPSIS...Due to the continuing upper level ridge over the Western US, high temperatures will be warm and summer-like for inland areas today. This evening and overnight, a trough will move through the Pacific Northwest bringing subsequent moisture and cooler temperatures to Northwest California. By the middle to end of the week, a ridge will build back in bringing warmer temperatures, especially for Friday. && .DISCUSSION...Stratus continues to erode away toward the coast, due to day time heating, bringing mostly clear skies and pleasantly seasonable temperatures for coastal areas today. With the clear skies inland and high pressure overhead, interior valleys will have slightly warmer than average high temperatures in the low to mid 80s. Coastal temperatures will range from the upper 50s to low 60s with breezy onshore winds building throughout the day. Another weak shortwave associated with a trough moving into the Pacific Northwest will traverse the region this evening and into the early morning allowing for some moisture and instability to migrate through. This combined with the increased temperatures today will enhance instability, bringing the potential for some light rain showers to pop up in the higher terrain areas of Trinity and Mendocino counties by this evening. The chance for thunder is non- zero, but with little mid-level moisture and low lapse rates, chances are low. NBM gives around a 10 percent probability to see thunder, while SREF gives around a 20 percent chance. Overnight tonight, the moisture brought in by the weak shortwave will aid in the development of a deepened marine layer and even some drizzle along the coast by early tomorrow morning. Also, widespread high altitude cloud cover tomorrow will lead to cooler temperatures for inland areas by tomorrow afternoon. A ridging pattern will develop by mid week and gradually warm the region through the end of the week, particularly the interior. For the interior, mid to high 80s are forecast for Thursday, while high 80s to low 90s are forecast for Friday. Also, some coastal regions could warm to the mid 60s by Friday with the help of offshore flow. Afternoon wind gusts are possible as well, with probabilities for wind gusts above 25 mph between 50 and 70 percent along most of the coast by Thursday. Ensemble members are starting to show some agreement on a weaker ridge persisting at least through Saturday. /JLW & /DS && .AVIATION...Skies have mostly cleared early this afternoon, although some MVFR stratus lingers in the Eel River Delta and south of Humboldt Bay. Low cloud and drizzle are expected to redevelop late this evening and overnight along the Redwood and portions of the Mendo coast...with most guidance trending toward stratus development, indicating ceilings remaining primarily MVFR. Otherwise VFR will prevail across the interior. && .MARINE...A weak northerly wind pattern persists. Winds continue to be accelerated south of Cape Mendocino where localized gusts up to 35 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 continue Tuesday. 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 Wednesday and Thursday will increase northerly winds in all zones. There is growing probability for gale conditions through that period. && .EKA WATCHES/WARNINGS/ADVISORIES... CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 3 AM PDT Wednesday for PZZ455- 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