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FXUS66 KEKA 232148

National Weather Service Eureka CA
248 PM PDT Wed Oct 23 2019

.SYNOPSIS...Offshore winds will bring mostly clear skies and
warmer temperatures along the coast over the next couple of days. 
Inland areas will remain unseasonably warm as well. Milder 
weather will arrive this weekend, but no rainfall is in sight. 


.DISCUSSION...Coastal low clouds and fog early this morning have
given way to sunny skies area-wide this afternoon. With high 
pressure shifting to our north across the Pacific NW, NE winds 
will continue to increase across the interior mountain ridges. 
Have no reason to differ from the earlier forecasts of gusty 
NE to E winds continuing to increase through tonight across the 
exposed mountain ridges of interior NW California. Easterly winds
will start begin to diminish Thursday. 

Warm temperatures will be the other newsworthy weather feature 
this week. Interior valleys of Mendocino county may top 90 degrees
Thursday and Friday afternoons, which will be well above the late
October averages in the 70s, but not record-breaking. Some 
coastal locations may have better odds at reaching record highs, 
particularly around Eureka on Thursday (record high of 76 set in 
2017). Forecast models limit any fog and stratus formation the 
next couple nights and mornings as offshore flow extends to the 
coast, though a light onshore breeze may return by Friday 
afternoon, bringing in some cooler marine air. Before that occurs,
would not rule out lower 80s just inland on Thursday afternoon, 
and a very warm start to the day on Friday as well.

The weekend will feature a cooling trend both at the coast and 
inland thanks to a dry cold front, with high temperatures dropping
back to near late October seasonal averages. Low temperatures 
will be frosty across many inland areas by the end of the weekend 
into early next week. Some stratus or fog may threaten portions of
the coast Friday night into Saturday morning, otherwise expect 
sunshine and dry weather to continue through early next week. 
Another bout of offshore winds may allow for some warmer 
temperatures at the coast again on Sunday or Monday afternoon. 


.AVIATION...Offshore flow should allow for VFR conditions to prevail 
through the TAF cycle. Gusty conditions will continue along the 
coast through this evening and will ease tonight. A period of low-
level wind shear will be possible late this evening through early 
tomorrow morning at KUKI. Gusty winds along the coast should help 
alleviate the impacts along the coast, but some low-level wind shear 
will be possible tonight and tomorrow at both coastal terminals. 


.MARINE...Northerlies will peak this evening and slowly weaken 
through Friday. Some gusts to Gale Force in strength will be 
possible this afternoon and evening, but overall coverage appears to 
be minimal. Steep, short-period seas have built in response to the 
increasing winds and will very slowly weaken through the end of the 
week. Small Craft Advisories are in place through at least late 
tonight as conditions slowly wane. Winds will increase once again 
late on Friday, with current guidance suggesting to Gale Force in 
strength early Saturday morning through early Sunday morning. Very 
steep, short-period seas will develop as a result, likely with some 
hazardous seas later this weekend. Otherwise, a waning northwest 
swell will linger through most of the forecast period.


.FIRE WEATHER...The Red Flag Warning remains valid through 
Thursday afternoon. Little has changed with guidance continuing 
to support sustained NE to E winds of 15 to 25 mph through 
Thursday morning across the warning area, with gusts to 40 mph 
over the highest exposed ridgetops likely. Sheltered areas, lower 
elevations, and valleys will have much lighter winds, so the 
warning area remains restricted to elevations above 2000 feet. 
Very low humidity will accompany the strong winds, with recoveries
to 15 to 25 percent tonight, while vegetation in the warning area
has seen little in the way of rainfall yet this season. Areas to 
the N of the warning area will also see gusty NE ridgetop winds, 
but those areas either will have higher humidity and/or have seen 
appreciable rainfall recently. 

Winds will gradually diminish on Thursday, but humidity will
remain very low through the afternoon. The airmass will cool and
marginally moisten heading into the weekend, but no rainfall is 
in sight. Another round of offshore winds is still possible around
Sunday and Monday, but the latest model guidance continues to 
be split regarding the strength of these winds, and whether or not
the combination of humidity and winds will once again reach Red
Flag criteria. /AAD&SEC


CA...Red Flag Warning until 5 PM Thursday for CAZ276-277.

     Small Craft Advisory until 3 PM Thursday for PZZ470-475.
     Small Craft Advisory until 9 AM Thursday for PZZ455.
     Small Craft Advisory until 3 AM Thursday for PZZ450.


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