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Area forecast discussion 
National Weather Service Eureka California
348 PM PDT Tue Oct 25 2016

Synopsis...brief dry break this morning, as a band of light rain
returned to northwest California by this afternoon. Rain will intensify
this evening, along with gusty south winds. Gusts of 40 to 50 mph
with higher gusts along ridge top locations are expected through
Wednesday daytime. Rain will be heavy at times along the coast, and
persist through Thursday. Wet weather will continue through early
next week.


Discussion...the active weather pattern continues for northwest California.
Water vapor imagery shows a complex upper level flow pattern over
the east Pacific Ocean. The east Pacific Ocean is dominated by a
broad scale upper level low with multiple vortices spinning
around. The vortex associated with the Monday low is now located
over the waters just west of Vancouver Island. At the same time,
there is a weak vortex spinning around it. There is another well
developed vortex, located about 1000 miles west of the or/California
border, spinning around. There are 2 additional vortices, 1 east
and 1 west of the mature vortex, spinning around. In short, there
are 5 vortices spinning around in the east Pacific Ocean. Due to
the proximity of individual vortices, they are spinning around
each other. With this upper level set up, do not expect the
pattern of trough over east Pacific Ocean to change much during
the forecast period through early next week.

From last night into this morning, there was a brief dry break.
However, the dry break didn't last long. Precipitation ahead of the
warm front moved into northwest California from the southwest. After the
warm front passage tonight, there will be a front stalling over northwest
California, and this will lead to extended period of rain, at least
through Thursday along the coast. Expect around one inch of rainfall
through Thursday. The highest rainfall amounts will be along the
coastal areas.

Do expect the winds to pick up this evening. South winds of 20 to 30
mph with gusts of 40 to 50 mph are expected for tonight into
Wednesday daytime. The highest wind gusts will be over exposed ridge
top locations. The strongest winds will be found in unpopulated
mountainous locations. Gusty winds should subside during the day on

Wet weather will persist through the rest of the forecast period
early next week. As discussed above, the upper level trough off the
West Coast is not going anywhere soon. With persistent SW-ly onshore
flow, do expect the continuation of the wet pattern. Confidence is
low in the details of timing and intensity of individual storm
systems. /Rcl


Aviation...ceilings have come up ahead of an approaching warm
front. Ceilings have actually come up to over 8kft along the Redwood
coast. Light rains have begun to spread across the area, although
some of this rainfall is not reaching the ground. Rains will
increase from the SW during the evening hours, and ceilings will
gradually drop again. S winds will increase as well, and this will
lead to some rain shadowing for the coastal taf sites. This will cut
down on rain intensities and slow ceiling declines. Wind gusts will
increase to over 25 kts after midnight at kcec and kacv. /Sec


Marine...southerly winds will increase rapidly through the evening
hours with speeds in excess of gale force over the north outer waters
and gusts over gale force over the S waters. A few gusts to near
storm force are possible for the north outer waters after midnight
tonight. Upgraded the gale watch to a warning with the 9 am update,
and have kept this unchanged for this package. The Gale Warning for
the S near shore waters will be marginal with respect to areal
coverage, but will be quite strong near Cape Mendocino. Will keep
the north near shore waters as a strongly worded Small Craft Advisory,
and will highlight the stronger winds downwind from Cape Mendocino.


Eka watches/warnings/advisories...
Northwest California coastal waters...Small Craft Advisory until 9 PM PDT Wednesday for pzz450.

Small Craft Advisory until 8 PM PDT this evening for pzz455-470-

Gale Warning from 8 PM this evening to 11 am PDT Wednesday for



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