Area Forecast Discussion
Issued by NWS Eureka, CA
Issued by NWS Eureka, CA
211 FXUS66 KEKA 161200 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 500 AM PDT Mon Sep 16 2024 .SYNOPSIS...A mix of sun and clouds is expected across the area today with some afternoon showers in the interior. Another round of rain showers is expected Tuesday through Wednesday with the heavier showers in the north. A drying and warming trend is expected late in the week. && .DISCUSSION...The upper level low is starting to move out of the area today, but there may still be some showers this afternoon over eastern Trinity, eastern Mendocino and Lake counties. In the heavier showers some areas could see local amounts over a quarter of an inch. Some warming is expected in the inland areas compared to Sunday, although most inland areas will remain in the 70s. Monday night a brief period of ridging is expected between the upper level lows. Temperatures will be chilly, but even the coldest valleys are only expected to drop into the upper 30s. Frost is possible in a few of the coldest valleys, but not likely at this point. At the coast some drizzle is possible as the marine layer returns. The next upper level low is expected to move down from the north just off the west coast Tuesday afternoon and overnight. The current NBM shows rain developing late Tuesday afternoon and evening, mainly Humboldt and Del Norte counties. Occasional showers are expected to continue through Wednesday afternoon. Current models show the highest rainfall totals around a half inch in the mountains of Del Norte county. These totals have trended down in the most recent model runs. This remains a low confidence forecast due to the uncertainty on the exact track of the upper level which will dictate where the heaviest precip falls. Currently there is a big spread between the 75th and 25th percentile of rainfall totals. The current forecast is generally on the lower end of this range and may need to be increased as it gets closer. There is a small threat for thunderstorms in eastern Mendocino and Lake counties Wednesday afternoon, but again uncertainty is high due to the differences in the placement of the low. Rainfall is generally expected to end Wednesday night. If clouds clear quickly enough the cool airmass could allow frost to form, but at this point it doesn`t look likely. Thursday is expected to see afternoon temperatures rebound quickly with highs in the low 80s in most of the interior valleys. Continued warming is expected with many areas reaching the low 90s for the weekend. MKK && .AVIATION...Early this morning the coastal terminals are active with changing cloud ceilings and a threat of some low level wind shear. While most model guidance showed 2000ft winds around 15-20kts, a few models were suggesting elevated winds near 30kts at KACV by this afternoon. That said, the threat is not significant enough to be added to the TAFs, yet should be considered all along the Redwood coast. Cloud coverage should remain fairly elevated through the day today before possibly surging into the coast again around sunset. More confidence on the stratus situation will arise as more high-res model guidance becomes available later this morning. Inland at KUKI, winds should be lighter than yesterday but will still pickup during the day from the west and calm come nightfall. && .MARINE...Northerly winds with gale force gusts and steep to hazardous seas with significant wave heights of up to 11 ft are present in the outer waters early this morning and should remain through mid-morning. Gradual improvement of the sea state is expected Monday evening through Tuesday. However, the sea state will continue to evolve through the work week. A front moving through the forecast area on Tuesday will force southerly winds, light rain/mist, and possible areas of dense fog/reduced visibilities in the coastal waters. Northerlies are forecast to strengthen again Thursday behind this passing upper level trof, creating conditions that could be dangerous for small crafts Thursday afternoon in the outer waters. && .EKA WATCHES/WARNINGS/ADVISORIES... CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 9 AM PDT Tuesday for PZZ450-455. Gale Warning until 9 AM PDT this morning for PZZ470-475. && $$ 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