730 FXUS66 KEKA 111119 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 419 AM PDT Thu Oct 11 2018 .SYNOPSIS...High pressure building into the Pacific Northwest will bring warming temperatures and clear skies for much of the weekend. A gradual cooling trend will start next week and coastal stratus will likely return. && .DISCUSSION...A shortwave is moving south across Oregon as high pressure builds into British Columbia and Washington. This shortwave moves across the area this morning although it shouldn't bring too many impacts. As this shortwave moves to the south and the high pressure builds into Oregon and Washington easterly winds set up across northwest CA. This should keep areas mostly clear and dry tonight. Frost is likely once again in the interior valleys of Trinity county. Friday temperatures will continue to warm across the area with inland areas seeing highs in the 80s and coastal areas in the upper 60s to low 70s. Friday night into Saturday the high pressure slowly moves to the east. This will bring a couple of subtle changes. Afternoon inland temperatures will continue to warm into the mid to upper 80s. Also, models are showing some indications of stratus returning on the Mendocino coast. Sunday the ridge moves directly overhead. Models are showing some southerly winds at 925 MB and 850 MB along the coast south of Cape Mendocino. This often indicates that a southerly surge of stratus will move north to at least Cape Mendocino and possibly farther. As the afternoon high temperatures increase this will diminish the potential for frost, although with the long nights it is still possible in the cold spots in Trinity county such as Hayfork and Ruth. Next week high pressure starts to very slowly shift off to the east. Inland temperatures will gradually cool through the back closer to normal. Highs will likely still be around 80 late in the week. As the ridge moves east the coverage of stratus will likely increase. The potential for frost in the inland areas will return as well. MKK && .AVIATION...Local pockets of stratus formed along the coast early last evening but a gradual increase in offshore winds early this morning has decreased the cloud formation. Since the easterly winds are not very strong the battle between stratus/fog formation may continue through the morning hours but by mid morning all coastal areas should be vfr. Interior areas will see some brief localized areas of fog/stratus where east winds are sheltered but like the coast any mvfr conditions will give way to vfr not long after sunrise. && .MARINE...Surface high pressure continues to reside over the northeastern Pacific while low pressure persists across AZ/NM. The tight pressure gradient between these two features over the coastal waters will continue to weaken today likely allowing small craft advisories to end later today. The short period wind swell will also subside leaving a smaller mid period nw swell and a southerly swell from 3 to 5 feet at 14 seconds through the weekend. && .FIRE WEATHER...A weak disturbance will continue to bring near to slightly below normal temperatures today across the interior. High pressure will then build into the area as a low forms off the central California coast. As a result, offshore flow is expected through the middle of next week with the strongest occurring Thursday night into Friday morning and again on Saturday night. Gusts to 25 mph are possible along exposed ridges of interior Mendocino, Humboldt, and Del Norte county. Poor RH recoveries mainly over the higher elevations are also expected across portions of the interior as warm and dry conditions persist into next week. && .EKA WATCHES/WARNINGS/ADVISORIES... CA...Frost Advisory until 9 AM PDT this morning for CAZ107-108. NORTHWEST CALIFORNIA COASTAL WATERS.. Small Craft Advisory until 5 PM PDT this afternoon for PZZ450-455-470-475. && $$ Visit us at http://www.weather.gov/eureka Follow us on Facebook and Twitter at: http://www.facebook.com/NWSEureka http://www.twitter.com/nwseureka For forecast zone information see the forecast zone map online: http://www.weather.gov/eureka/zonemap.png