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000
FXUS66 KEKA 181201
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
501 AM PDT Thu Apr 18 2024

.SYNOPSIS...Dry, mild temperatures are expected to continue for
the remainder of the week. A shallow marine layer will return
early Friday morning. Temperatures will begin a cooling trend this
weekend as a fast-moving shortwave trough and a weak cold front
moves through, with very light precipitation or sprinkles in Del
Norte on Saturday. Breezy NW winds will redevelop along the North
Coast with a shortwave ridging building over the area on Sunday.


&&

.DISCUSSION...Another day with quiet weather conditions across
Northern California. High pressure over the area is bringing
increasing subsidence aloft, weak offshore flow, and mostly clear
skies early this morning. Latest satellite imagery depicts high
level moisture from the Pacific approaching the area. High clouds
are expected to stream across the area this afternoon and evening,
bringing a beautiful sunset. Temperatures will continue to
slightly warming today, even along the coast. Interior valley`s
temperatures are forecast to be in the upper 70s to low 80s, while
the coastal area are expected to reach into the 60s before the
light onshore flow develops in the afternoon. A classic southerly
stratus surge will develop late tonight/early Friday morning,
with a shallow marine layer charging up and lapping the Mendocino
Coast.

Friday, the high pressure break down and pass over while a fast-
moving shortwave trough and a weak surface front approaches the
area. The flow will become zonal which may slightly deepen the
marine layer and cool near the coastal areas 3 to 5 degrees. Interior
areas are expected to warm up another few degrees.

The aforementioned weak front will clip the northern portion of
the area on Saturday. This will bring a low chance of light rain
or sprinkles to coastal Del Norte County by Saturday afternoon.
Elsewhere, expect an increase in cloud cover, a "cool" down in
temperatures and breezy west-northwest winds. A shortwave ridge
will begin to build in quickly over the Pacific Northwest and
Northern California in the wake of the front on Sunday.
Breezy northwesterly winds will redeveloped along the coastal
areas with a tightening pressure gradient, mainly along the North
Coast. NBM probabilities indicates there is a 60-75% chance of
wind gusts around 30MPH along the exposed ridges and coastal
headlands of Del Norte County and Cape Mendocino.

Ensembles are showing an amplifying upper-level trough/deepening
a cut off low approaching the area early next week. Cluster
analysis are align with the deterministic and ensemble models with
this system approaching the area. However, there is a lot of
uncertainty with the location and timing with the cutoff trough.
GFS and ECMWF are fairly align remain the Pacific Storm well
offshore and moving southward toward Baja California by mid week,
while the Canadian indicates this storm settling over the West
Coast. Stay tuned!

Velez


&&

.AVIATION...VFR conditions and light winds across all terminals will
continue this morning beneath an axis of high pressure. Light
offshore flow at coastal terminals will deter widespread marine
stratus development, although minor wind reversals south of Trinidad
and within Humboldt Bay may encourage a shallow marine layer to move
inland and produce scattered low ceilings and reduced visibility
early this morning at ACV. Current observations have yet to align
with hi-res models, but TAFs will reflect potential for intermittent
stratus/mist. Otherwise, NW winds will increase this afternoon with
daytime heating before quickly turning ESE overnight to resume
offshore flow.


&&

.MARINE...Nearshore winds rapidly diminished early this morning as the
coastal jet migrates west. Wave heights will continue to decrease in
response, with >10 ft seas lingering in the outer waters and
downwind of Cape Mendocino. Winds and seas will continue to subside
beneath a broad area of high pressure building into the CA coast,
allowing wave heights to diminish to 5-6 feet by late Friday. An
upper level shortwave and associated frontal passage are expected to
clip NorCal Saturday afternoon, generating a rapid resurgence of
northerly winds and responsive wind waves. Small craft conditions
are likely late this weekend into early next week as the coastal
pressure gradient tightens ahead of another building ridge.



&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
None.
NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory until 5 AM PDT early this morning for
     PZZ450-455.

     Small Craft Advisory until 3 AM PDT Friday for PZZ470.

     Small Craft Advisory until 9 PM PDT this evening for PZZ475.

&&

$$

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