Area Forecast Discussion
Issued by NWS Eureka, CA

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FXUS66 KEKA 221121

National Weather Service Eureka CA
421 AM PDT Fri Sep 22 2017

.SYNOPSIS...Warming trend in store for NW California, and will
continue through next week. Little or no precipitation is expected
for the next seven days.


.DISCUSSION...A chilly start to your Friday morning. Some areas in
Trinity County and interior Mendocino County saw temperatures
dropped into the mid 30s overnight. The Frost Advisory would be in
effect through 8 am this morning for those areas. For today, high
temperatures in the interior will be about 10 degrees warmer than

The broad upper level trough that caused the wet and cool weather
over our area would slowly move towards the east. The upper level
ridge will build into the West Coast from the west. This will lead
to rising heights, and thus warming temperatures through the weekend
into early next week. Highs will be in the 70s for today and
Saturday over interior locations, 80s on Sunday and Monday, and 90s
on Tuesday.

As the ridge of high pressure builds into the area, do not expect
precipitation in the next 7 days.


.AVIATION...High pressure continues to slowly build into the area.
This is bringing offshore flow and drier air which is keeping most
areas clear this morning. The exception is some areas of stratus in
Humboldt and Del Norte counties. Any lingering stratus should clear
fairly quickly once the sun comes up and VFR conditions are expected
to prevail through the day. Breezy conditions are expected along the
coast north of Cape Mendocino with the strongest winds near Crescent
City. Tonight offshore flow is expected to keep skies mainly clear.


.MARINE...Currently the northwest swell is dominating the waters.
This is expected to change later today. High pressure building in
will start to tighten the pressure gradient and increase the
northerly winds this afternoon. At the same time the NW swell will
continue to diminish. Small craft advisories have been issued for
the outer waters where the winds will be strongest. Current HiRes
model guidance keeps the strongest winds 10 to 20 miles offshore in
most areas. The exception will likely be just south of Cape
Mendocino and Point St George where local gusts to 30 kt are
possible. These winds will increase steep short period waves to
around 8 feet at 7 seconds over the outer waters by late tonight.
The waves in the inner waters are expected to remain below small
craft advisory, but this will need to be watched.

Winds and seas are expected to remain elevated through the weekend
and into Monday. Steep waves are expected to peak around 10 feet.
Model solutions start to diverge on Tuesday. The GFS keeps winds
around 20 to 30 kt while the ECMWF diminishes them more quickly.
Generally took a blend of these solutions. Wednesday through Friday
the models are in decent agreement on the winds diminishing to
around 5 to 15 kt. Another northwest swell is expected starting on
Tuesday, but it looks to be only 3 to 5 feet at 12 to 14 seconds.


CA...Frost Advisory until 8 AM PDT this morning for CAZ107-108-110-

NORTHWEST CALIFORNIA COASTAL WATERS...Small Craft Advisory from noon today to 8 PM PDT Tuesday for



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