Area Forecast Discussion
Issued by NWS Eureka, CA
Issued by NWS Eureka, CA
665 FXUS66 KEKA 121345 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 543 AM PDT Wed Jun 12 2024 .SYNOPSIS...Hot and dry weather today for most of the interior. Strong and gusty northerly winds expected again today for coastal ridges and headlands. Temperatures trend down on Thursday, followed by more substantial cooling over the weekend as strong and gusty westerly to northwesterly winds strengthen in the interior. && .DISCUSSION...Dry weather (no rain) is forecast to continue through the end of the week and most likely for the weekend. Temperatures will remain 10-20F above normal today in the interior. Temperatures are forecast to peak in the mid 90s to 101F in Lake, Trinity and interior Mendocino counties. Heat risk is forecast to be moderate in these hot interior locations. Heat risk is forecast to be low in Humboldt and Del Norte. The heat risk is then forecast to decrease on Thursday, but high temperatures will probably remain slightly above mid June normals. For coastal areas, stratus has built back over Humboldt Bay and extended all the way up the coast to the Oregon border again. Stratus also extended deep into North Coast river valleys, though the depth appeared no higher than 2kft. The low overcast will scour out this afternoon as northerlies ramp up in response to interior heating. Breezy north to northwesterly winds will gusts to 25-30 mph this afternoon. Locally stronger gusts of 35-45 mph are highly probable at the coastal headlands and over exposed ridges of SW Humboldt county (King Range). NBM remains consistent with temperatures diminishing on Friday as upper level ridging shifts south and a trough develops over the Pacific NW. Stronger westerly to northwesterly winds are expected to develop on Friday across the interior especially interior Mendocino and Lake counties. More substantial cooling along with stronger west to northwest winds are expected in the interior this weekend as another 500mb trough dips down from the NW. Strongest winds will most likely occur on Sunday with the passage of a shortwave trough. With fine grassy fuels cured, the strong westerly to northwesterly winds may pose a slight risk for rapid spreading grass fires. The highest risk appears to be in Lake and perhaps eastern Trinity and southern Mendocino. This trough is forecast to be relatively dry and right now the potential for any precipitation is quite meager, 5-10% chance for mostly Del Norte late in the weekend. The cooler/drier air will also result in chilly overnight temperatures once winds decouple. There is a chance (20-40%) for brief morning frost in the colder valleys of Trinity and eastern Humboldt counties on Sunday. The frost threat will persist into Monday morning with about the same probability of occurrence. Also, rain possibilities increase early to mid next week (June 17-19), though still quite meager with NBM probabilities for 0.10in or more in 24 hours no more than 22% for mostly Del Norte and northern Humboldt counties. NBM has temperatures trending upward by mid week, however the trough may linger into mid next week and strong warming appears unlikely at this point. DB && .AVIATION...Stratus has returned to the coastal terminals early this morning, with IFR ceilings being reported. These could briefly dip down to LIFR around sunrise, before lifting by mid-morning. Northerly winds are forecast to increase this afternoon. Gusts at CEC could exceed 30 kts while gusts at ACV could exceed 20 kts. Winds will ease after sunset. Stratus will likely return tonight, starting first around Humboldt Bay, then advecting toward CEC. UKI will stay VFR through the day, with clear skies and typical afternoon breezes. JB && .MARINE...Gale force northerlies continue early this morning in the outer waters and the expansion fan south of Cape Mendocino. The near- shore sea state is dominated by steep wind waves of 9 to 10 feet along with a mid-period NW swell at around 6 feet. Both winds and waves will increase today with gusts nearing 50 knots this afternoon. Significant wave heights will peak this evening at around 12-15 feet before winds begin to ease Thursday night into Friday morning north of Cape Mendocino. Winds in the expansion fan south of Cape Mendocino look likely to stay at or near gale force into the weekend. The sea state will continue to be dominated by steep wind waves and a series of mid-period NW swells. Significant wave heights will gradually diminish, dipping below 10 feet into the weekend. JB && .EKA WATCHES/WARNINGS/ADVISORIES... CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 3 AM PDT Friday for PZZ450. Gale Warning until 9 PM PDT this evening for PZZ455. Gale Warning until 9 AM PDT Thursday for PZZ470. Gale Warning until 3 AM PDT Friday for PZZ475. && $$ 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