Area Forecast Discussion
Issued by NWS Eureka, CA
Issued by NWS Eureka, CA
356 FXUS66 KEKA 161214 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 514 AM PDT Sun Jun 16 2024 .SYNOPSIS...Dry weather is expected through at least the first half of this week. Interior temperatures below seasonal normals today, then begin a slow warming trend through the work week. Breezy to windy westerly to northwesterly winds develop today. && .DISCUSSION...Stratus has intruded most interior valleys southern Humboldt and Del Norte early this morning. This cloud should mix out by late morning. Latest satellite WV imagery is showing a large longwave trough currently in place over the PNW, with a weak tropographic fold and associated shortwave digging through this trough, currently over the NEPAC. These two features will act to keep afternoon highs similar to Saturday, reaching around 5 to 10 degrees below climatological normal this afternoon. The primary concern with this feature looks to be wind, and gusts from 25 to 35 mph are likely across Lake and southern Mendocino counties this afternoon, and latest NBM ensemble guidance is indicating a chance (20 to 30%) of gusts exceeding 40 mph at Cow Mtn and south of Cobb in Lake County. With afternoon RH values forecast to reach the low 20 to teens this afternoon this weekend, there exists a slight risk for rapid spread of grass fires today in Lake county. See Fire Wx section for more details. Otherwise, Slightly cooler air and continued dry conditions with clear skies should result in chilly overnight temperatures once winds decouple. A brief morning frost is expected early Monday morning in the colder valleys of southern Trinity and eastern Humboldt counties as this shortwave progresses east of the area, building high pressure over the great basin and driving light, drying NE winds early Monday morning across much of the interior. Afternoon high temperatures are forecast to slowly trend back toward climatological normals next week, with longwave troughing continuing aloft well into the work week. Afternoon highs may creep back up to above normal late this week as ridging noses in from the west. && .AVIATION...Coastal stratus is basically non-existent along the immediate coast with MVFR ceilings and visibilities along the Eel River Valley. Winds have died down overnight from yesterday which will remain calm into late this morning with low level wind shear possible over southern Mendocino and Lake counties associated with a low level jet. By late morning to early afternoon, northwesterly winds will pick back up at all terminals and continue into this evening. Any MVFR conditions will dissipate with the arrival of stronger winds. && .MARINE...Gales are in effect for the southern inner and outer waters through today, with the southern inner zone lasting a bit longer into the evening. Steep square waves return this morning for the northern waters, bringing 6 to 8 ft wave heights at 6 to 8 seconds...which will last through to Monday and possibly Tuesday for the northern outer waters. Gale conditions will persist in the lee of Cape Mendocino as the northerlies accelerate around the Cape, to the south. /EYS && .FIRE WEATHER...Breezy to windy west to northwest winds are expected to develop today, with gusts of 25 to 35 mph expected across Lake, Trinity, and southern Mendocino counties, and a chance (20 to 30%) for gusts to reach above 40 mph at Cow Mtn and around Cobb in Lake County. Dry conditions with low daytime RH`s in the 20`s and teens are expected to continue this afternoon. Winds are forecast to weaken late tonight and turn NE, ushering in a drier airmass and possibly driving RH values into the low teens on Monday. The strong winds and low humidity will yield an elevated fire weather threat Sunday and Monday, particularly for the south and east side of Lake County. A Red Flag Warning remains in zone 264 (southern Lake), from today through early Monday, primarily for the possibility of rapid spreading grass fires. && .EKA WATCHES/WARNINGS/ADVISORIES... CA... Frost Advisory from 3 AM to 9 AM PDT Monday for CAZ106-108. Red Flag Warning from 10 AM this morning to 8 PM PDT Monday for CAZ264. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 9 PM PDT this evening for PZZ450. Gale Warning until 9 PM PDT this evening for PZZ455. Small Craft Advisory until 9 PM PDT Monday for PZZ470. Gale Warning until 3 PM PDT this afternoon 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