Area Forecast Discussion
Issued by NWS Eureka, CA

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27

299
FXUS66 KEKA 152157
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
257 PM PDT Tue Oct 15 2019

.SYNOPSIS...Dry weather will continue tonight. A front will move
across the area Wednesday afternoon and evening, generating light
to moderate rain. Cooler, showery weather will follow for the
remainder of the week with more widespread rain on Saturday.

&&

.DISCUSSION...Low clouds and fog lingered across much of the
coastal areas into early afternoon. A bank of stratus continues
along the N Redwood Coast as of this writing. In addition, high
clouds continue to stream across most of the County Warning Area.

The marine layer appears to be about 2000 ft deep this afternoon,
and the layer is expected to deepen further tonight ahead of the
approaching storm system. Increasing southerlies in advance of a
surface front will likely mix out the fog and eradicate the marine
layer completely by Wednesday morning.

A wet weather pattern will return on Wednesday and last into the
weekend. The first front is expected to move across the area
Wednesday afternoon and evening with rainfall amounts ranging
from an inch in Del Norte county to a tenth of an inch or less in
southern Mendocino interior. Light snow showers will also be
possible on the mountain tops of Trinity County late Wednesday
night. No snow impacts are expected, however.

Additional shortwaves in moist NW flow will follow Thursday through
Saturday. Once again, the highest rain amounts and rain chances
will be north of Cape Mendocino. Ensemble guidance and deterministic
models indicate the wettest system arriving Saturday morning.
1/2" to 1" of rain will be possible for Del Norte and northern
Humboldt counties. This spell of wet weather will be
mostly a nuisance and no significant hydro concerns are expected
at this time. Conditions should start to dry out and warm up late
in the weekend and early next week as a broad flat ridge builds
over the NE Pacific. /SEC

&&

.AVIATION...Dense stratus offshore this morning will begin to clear
slightly at the coastal terminals.  Onshore flow, from High pressure
along with dry air aloft, will improve visibility briefly in the
afternoon and early evening at KCEC and KACV.  Offshore stratus and
light winds persist and obscurations to visibility will redevelop as
inland temperatures cool.  LIFR categories for much of the day into
the evening at the coastal terminals. KUKI remains in VFR flight
conditions for most of the day.  Light winds and Few clouds are
expected. /EYS

&&

.MARINE...Southerly winds will increase late tonight as a cold
front approaches, peaking at 15 to 25 kt over the outer waters
between Cape Mendocino and Pt St George around midday Wednesday.
Periods of rain will accompany the front much of Wednesday and
Wednesday night, followed by light winds and just a few stray
showers on Thursday and Friday.

Seas will be much more impactful than the winds this week, mainly
due to a NW swell arriving later on Wednesday and building on
Thursday. Seas on Wednesday will build with a combination of the
forerunners of the northwesterly swell and steeper southerly seas
ahead of the cold front. Confused and rather chaotic seas will
reach 8 to 10 ft combined on Wednesday. The main swell will then
build in and reach around 16 ft at 16 seconds on Thursday, perhaps
lingering into Friday before diminishing to around 11 ft by
Saturday. /AAD&SEC

&&

.BEACH HAZARDS...A large NW swell will begin to move through the
coastal waters late on Wednesday. The swell will continue to build
through Thursday, leading to larger breaking waves on NW CA
beaches, possibly reaching around 20 ft on W to NW facing beaches.
This will lead to increased wave run-up on beaches with waves
topping large rocks and jetties. These large waves can be erratic
and unpredictable, and with sand bar profiles still more typical
of summer, locally larger waves may result. Beaches with a steeper
slope may be particularly dangerous. Beachgoers are urged to use
extra caution near the surf zone as these large waves will be
capable of sweeping people into the cold and turbulent ocean
water. Have already been including this in the Hazardous Weather
Outlook over the last couple of days, and will be deciding on
additional text products and social media tonight and Wednesday.
/AAD&SEC

&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...None.
NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory from 9 PM Wednesday to 8 AM Friday
      for PZZ450-455-475.
     Small Craft Advisory from 8 AM Wednesday to 8 AM Friday
      for PZZ470.

$$

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



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.