Area Forecast Discussion
Issued by NWS Eureka, CA

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FXUS66 KEKA 171202

National Weather Service Eureka CA
502 AM PDT Wed Jul 17 2019

.SYNOPSIS...Dry weather is expected across most of northwest
California through the middle of next week. High temperatures
will generally be in the 80s to low 90s across the interior, with
hotter spots warming into the mid to upper 90s. In addition,
abundant sunshine will occur across inland areas this week, while
periods of marine stratus continue for most of the coast.


.DISCUSSION...Quasi-zonal flow aloft is impinging upon the PAC NW
region Wednesday morning, while northwesterlies were occurring
over California. High level clouds within the zonal flow to the
north are spilling southward across portions of NRN CA. Meanwhile
at the surface, moderate north-northwesterly boundary layer flow
is aiding in stratus banked up against the Coast Range in the
vicinity of coastal Humboldt County and the Eel River Valley.
Short term model guidance indicates stratus will dissipate during
the morning, which may give way to sunshine sufficient for high
temperatures in the mid 60s to low 70s along the coast. However, a
reinforcing shot of marine stratus is forecast to spread across
coastal areas tonight.

Additional periods of marine stratus will be possible along the
coast during the next seven days. Farther inland, mainly clear
skies will prevail, which will aid in warm to locally hot
temperatures across interior valleys...with the hottest
temperatures expected late this weekend into the middle of next
week. Otherwise, near zero rain chances are expected throughout
the short and long term forecast periods.


.AVIATION...Somewhat patchy marine stratus continues to impact
the Humboldt and Del Norte coastlines Wednesday morning, with a
high degree of variability. While these low clouds have developed
and are expanding in the vicinity of CEC, as of 1130Z the terminal
has remained VFR. ACV has been impacted by these clouds more
directly, with ceiling heights generally hovering near the
IFR/MVFR breakline of 1000 ft AGL, although even here occasional
VFR breaks have been observed. Other smaller coastal terminals,
specifically FOT, have observed even lower ceilings. For the
remainder of the morning, this stratus is expected to continue to
impact all coastal terminals to varying degrees, likely moving in
and out of the terminal sites and causing flight categories to
swing back and forth from IFR to VFR. Stratus is expected to
dissipate during the mid to late morning hours, first at CEC and
later at ACV, and VFR conditions are expected for several hours
during the afternoon. Stratus is expected to return again during
the evening, with ceilings likely to be highly variable along the

As has been the case for the past several days, VFR conditions
will continue at UKI. /BRC


.MARINE...Northerly winds are peaking early this morning across
the waters. While winds will decrease across the northern waters
through the morning winds across the southern waters will remain
fairly steady but slowly begin to diminish this evening into
Thursday morning. Steep waves will persist across the southern
waters through Thursday therefore have extended the small craft
advisory for the southern waters through at least Thursday
afternoon. A modest southerly swell will also continue to impact
the waters through Thursday, with heights around 2-3 feet around
16 seconds.

On Thursday the offshore pressure gradient will begin to tighten
leading to a rapid increase in northerly winds by the afternoon.
Winds will be strongest across the outer waters and near Pt. St.
George and Cape Mendocino where sustained winds of 20-25 kts with
isolated gusts to 35 kts will be possible Thursday afternoon
through Saturday morning. These strong northerly winds will also
lead to steepening short period seas peaking Friday into Saturday
morning. Sea heights of 9-11 feet around 9 seconds will be
possible across the outer waters with 6-8 feet around 6 seconds
across the inner waters and a hazardous seas watch has been issued
for the northern outer waters Friday through Saturday morning.
Decided to hold off on one for the southern outer waters at this
time due to the limited spatial extent. Conditions will begin to
improve Sunday through early next week. /WCI


     noon PDT today for PZZ470.

     Hazardous Seas Watch from Thursday evening through late Friday
     night for PZZ470.

     Small Craft Advisory until 3 PM PDT Thursday for PZZ455.

     Small Craft Advisory until 9 PM PDT Thursday for PZZ475.



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