Area forecast discussion
National Weather Service Eureka California
340 am PDT sun may 19 2013
Synopsis...high pressure over the region will allow warmer
temperatures and drier conditions to continue into Monday. A low
pressure system approaching from the north will bring cooler
temperatures to the region along with a threat of showers north of
Cape Mendocino Tuesday through the end of the week.
&&
Discussion...low clouds across Humboldt County this morning with
increased northerly winds keeping low levels mixed inhibiting fog
development. Pressure gradient will continue to tighten as high pressure
offshore interacts with thermal trough across the interior with
breezy conditions developing along the coast late this morning.
Clouds will diminish this morning...but expect clouds to linger
through late morning/early afternoon around the Bay where the
onshore gradient is greatest. Dry weather and warm temperatures will persist
through Monday as upper ridge offshore prevails. Models remain in
good agreement with an upper trough digging down the West Coast Tuesday
dampening the upper ridge. Models show plenty of cold air with
this system temperatures 2-3 Standard dev below normal. Thickness values drop
to 540-550dm Tuesday night through Thursday with snow levels dropping to
around 3-4 kft as a result. This may result in some snow
accumulation above 5kft Wednesday and Thursday...however...confidence is
fairly low at this time. Additionally...frost...and possibly even a
freeze...will be possible Thursday and Friday mornings... but will be
dependent on overnight sky cover. Trough axis begins to shift east
Friday bringing drier weather and warmer temperatures to the region heading into
next weekend.
&&
Aviation...MVFR cloud layer this morning will scour out by this
afternoon as gusty northerly winds develop. Skies should remain
mostly clear tonight...except for brief and patchy MVFR ceilings in
the Delta.
&&
Marine...high pressure will build toward the Pacific northwest today as
thermal low pressure develops over California. Northerly winds
should peak to 40 knots...mainly in the outer waters...this
afternoon and evening. The strong north winds will generate
steep seas around 11 feet at 10 seconds late this afternoon
into this evening. This is borderline for a hazardous seas
warning. Thus issued a warning for seas inside 10nm tonight.
North winds should diminish slightly Monday and Tuesday...but seas
will probably remain elevated and steep through middle week.
&&
Eka watches/warnings/advisories...
Small Craft Advisory from 7 am this morning to 5 am PDT Monday for pzz450.
Small Craft Advisory from 7 am to 3 PM PDT today for pzz470.
Small Craft Advisory from 7 am this morning to 5 PM PDT Monday for pzz455.
Hazardous seas warning from 6 PM this evening to 5 am PDT Monday for pzz450-455.
Gale Warning from 3 PM this afternoon to 5 PM PDT Monday for pzz470.
Gale Warning from 7 am this morning to 5 PM PDT Monday for pzz475.
&&
$$
Visit US at http://www.Weather.Gov/Eureka
Follow US on facebook and twitter at:
http://www.Facebook.Com/US.Nationalweatherservice.Eureka.Gov
http://www.Twitter.Com/nwseureka
