Area Forecast Discussion
Issued by NWS Eureka, CA
Issued by NWS Eureka, CA
508 FXUS66 KEKA 232105 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 205 PM PDT Thu May 23 2024 .SYNOPSIS...Near to below normal temperatures continue in the interior, especially in the early mornings. Dry, clear skies today will diminish tomorrow as a trough moves through Friday. && .DISCUSSION...Chilly temperatures this morning have warmed up to near normal high temperatures. Lingering stratus last night has lifted. Northerly breezes are anticipated to ease early this evening along the coast, giving way to light westerly and southerly breezes bringing the stratus back to the coast. Clear skies and dry weather associated with a ridge aloft will bring the potential for a chilly morning in the interior valleys of eastern Humboldt and Trinity counties, though temperatures will be a few degrees warmer than last night. The coastal areas will be much warmer than last night as the influence of stratus will prevent radiational cooling. Stratus is expected to diminish in the afternoon hours Friday. A weak shortwave moving through on Friday will bring more moisture into the area, with at the very least clouds if not some drizzle or light rain. HREF has the chance of measurable precipitation along the coast at 80%, with also high probabilities over the higher terrain, especially in the King Range and Trinity Alps. NBM probabilities are more pessimistic, but model soundings do point to some widespread moisture indicative of drizzle, perhaps even into the interior. A ridge will build back in Sunday and into the early week, warming temperatures back up in the interior to 5 to 10 degrees above normal. The coast is unlikely to receive the warming trend as the ridge will strengthen the marine inversion which will continue the threat of stratus. Ensembles are beginning to converge on a trough mid-week moving through the Pacific Northwest, which is largely constrained to the north of California, but NBM does show a low chance of some light, measurable precipitation reaching us. There is greater uncertainty on the overall pattern late next week as ensembles begin to diverge. JB && .AVIATION...Skies are clear across the area this afternoon aside from a few high clouds. The HREF is showing a 70 percent chance of IFR ceilings coming in by 07Z at KACV. Probabilities increase later in the night. There is some uncertainty on how low these ceilings will come in. For now have them starting in the MVFR category and quickly dropping to IFR. This may need to be adjusted as it get closer and is potentially sampled by nearby Metars. This doesn`t look like it will make it as far inland as KUKI at this point, but it will make it into many of the river valleys closer to the coast. The next question will be how much clearing there will be at the coast Friday afternoon. It looks like it will push back towards the coast and the coastal airports may see intermittent clearing and lifting ceilings. It looks like this clearing will be fairly brief, but ceilings may lift into MVFR. Winds will be lighter than today. MKK && .MARINE...Winds have started to diminish this morning and will continue to diminish this afternoon and tonight. These winds as well as the seas do look like they will diminish slower than previously expected so have extended the small craft advisories for some of the zones. The winds are expected to be the lightest Friday in the middle of the day. The northern waters should see a period of 5 to 10 kt north winds while south of Cape Mendocino will see winds drop to 10 to 15 kt. In addition to the wind driven seas there is a northwesterly swell around 3 to 5 feet at 11 seconds. This is expected to diminish tonight and combine with the diminishing wind wave. There is also a small southerly wave as well around 2 feet at 15 seconds. Winds will increase again Friday night and Saturday These winds are expected to persist around 15 kt in the northern waters and around 20 kt in the southern waters. These speeds are expected to remain fairly persistent through Monday. The models are generally showing increasing winds mid to late in the week. Waves will be mainly wind driven until late Sunday. A small southwest wave of 2 feet at 15 seconds and a small northwest wave of 3 feet at 10 seconds moves in on Sunday night and Monday. Heights and periods gradually diminish with both these waves into Tuesday. MKK && .EKA WATCHES/WARNINGS/ADVISORIES... CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 9 AM PDT Friday for PZZ455-475. Small Craft Advisory until 9 PM PDT this evening 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