Point St. George to Point Arena between 60 and 150 NM Offshore Forecast
|Tonight...S Winds 10 To 15 Kt, Becoming S To Sw 10 To 20 Kt. Seas 5 To 6 Ft.|
|Fri...Sw Winds 5 To 15 Kt, Becoming S To Sw 10 To 20 Kt. Seas 5 To 7 Ft.|
|Fri Night...Sw Winds 5 To 15 Kt, Becoming W To Nw. Seas 5 To 6 Ft.|
|Sat...N Winds 5 To 15 Kt. Seas 4 To 6 Ft.|
|Sat Night...N Winds 10 To 20 Kt. Seas 4 To 6 Ft.|
|Sun...N Winds 10 To 20 Kt. Seas 4 To 7 Ft.|
|Sun Night...N Winds 10 To 20 Kt. Seas 4 To 7 Ft.|
|Mon...N To Nw Winds 10 To 20 Kt, Becoming Nw 5 To 15 Kt. Seas 4 To 6 Ft.|
|Mon Night...Nw Winds 5 To 15 Kt. Seas 4 To 5 Ft.|
|Tue...W To Nw Winds Less Than 10 Kt. Seas 5 To 6 Ft.|
|Tue Night...S To Sw Winds 5 To 15 Kt, Becoming S 10 To 20 Kt. Seas 5 To 6 Ft.|
| Area Forecast Discussion|
National Weather Service Eureka CA
312pm PDT Thu September 17 2020
Areas of smoke and haze will continue for the interior through the next few days. Low pressure currently offshore will bring a chance of light rainfall north of Mendocino County tonight and Friday as it moves onshore.
The forecast area west of the fires continues to experience vast improvements in air quality thanks to deep-layered southerly wind flow. Daytime heating allowed for patches of improvement from the coastal stratus and poor visibilities. However, the stratus eventually filled back in, aided from an abnormally moist airmass advecting in from southwesterly surface flow. Dewpoints remain quite high from this occurrence, with coastal dewpoint temperatures hovering in the low to mid 60's, creating a humid and balmy feel to the air at times.
The forecast is on track for a period of light showers to envelop the area with an approaching upper-level trough, beginning in the early morning hours tomorrow. There has been little change in the latest run-to-run model solutions for Quantitative Precipitation Forecast, so confidence in good for measurable precipitation ranging from several hundredths to a tenth of an inch in Humboldt county, and a tenth to a quarter inch into Del Norte county. Precipitable water values will be 2 to 2.4 standard deviations above normal for the aforementioned areas through this event, giving confidence in the Quantitative Precipitation Forecast and perhaps hope for some overachieving showers.
High pressure will return with drier weather this weekend and early next week. Some overnight/morning light offshore flow may help to bring some brief periods of smoke back across our area at that point, but in far less magnitude than last week.
In the longer term, the GFS 5-wave and long-range ensemble guidance are indicating long-wave troughing over the northeast Pacific into perhaps an omega blocking pattern...thus may have another chance of rain sometime around late next week or next weekend.
Southerly winds from 10 to 15 kt are forecast to spread east across the coastal waters during Friday as a weak frontal boundary approaches the region. Winds will then become weak during Friday night, followed by 15-20 kt northerlies Saturday and Sunday. The increasing northerlies will likely require a small craft advisory over the outer waters by Saturday evening.
.EKA WATCHES/WARNINGS/ADVISORIES... CA...None. NORTHWEST CALIFORNIA COASTAL WATERS...None.