Area Forecast Discussion
Issued by NWS Medford, OR

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FXUS66 KMFR 241250

Area Forecast Discussion
National Weather Service Medford OR
450 AM PST Fri Nov 24 2017

.DISCUSSION...Showers are slowly dissipating this morning with the
heaviest action in northern California, mostly from Mt Shasta
eastward. However, showers, although light continue over the west
side. With this mixing, fog and low stratus are not nearly as
abundant as expected this morning, but should increase a bit near
sunrise as the showers continue to taper off and low level mixing
decreasing. The zonal flow pattern will transition to a weak ridge
which will bring a break in the wet pattern today into tonight.
With the cooler air mass over the region the high temperature
today will not be as warm as the past several days.

The weak upper level ridge shifts east Sunday ahead of the next
system that moves in on an approaching deepening upper level
trough. After a warm front moves through Saturday morning winds
increase aloft and the pressure gradient from Redding to Medford
increases. Models continue to show 700 MB winds increasing to over
70 kt east of the Cascades, but the timing of each model run
slips the timing of this farther back with these stronger winds
now not being shown until Saturday evening, or 06Z. With this
shifting in the models will leave the watch up for the day shift.
This front will bring heavy, but brief, rain to the south coastal
range and then eastward through the day Sunday as it sweeps
eastward. Snow levels drop behind the front to Cascade Pass
levels, but the bulk of the front will have moved through and snow
amounts should not be high at the passes.

Models are in good agreement with the upper low now sweeping into
the california coast midway between the bay area and Cape
Mendocino Monday morning, shifting the bulk of the precip south
of the forecast area as it moves to the southeast during the day
Monday. -Sven


.AVIATION...24/12Z TAF CYCLE...From the Cascades west...Mixing
with lingering showers are prevent widespread fog and low stratus
from developing this morning, but as we reach sunrise this
activity may subside enough to allow some minor development. By
late morning VFR conditions will prevail through the night. -Sven


.MARINE...Updated 330 AM PST Friday 24 Nov 2017...Weak high
pressure building into the area will bring calmer conditions to the
coastal waters today into tonight. A strong front will bring
strengthening south winds Saturday, with gales and very steep seas
possible late Saturday afternoon through Saturday night. There is
increasing confidence that gales will impact most the waters beyond
5 nm from shore as well as within 5 nm near Cape Blanco. Very steep
seas are possible across all areas during this period. Seas will
remain high and steep to very steep on Sunday. High and steep seas
will continue into early next week. On Wednesday, a high long period
west swell is expected to build into the waters. Seas on Wednesday
may build into the 15-20 foot range. /CC


OR...High Wind Watch from Saturday afternoon through Sunday afternoon
     for ORZ030-031.

CA...High Wind Watch from Saturday afternoon through Sunday afternoon
     for CAZ085.
     High Wind Watch from Saturday afternoon through Sunday afternoon
     for CAZ081.

Pacific Coastal Waters...Gale Watch from Saturday afternoon through
late Saturday night for PZZ350-356-370-376. Hazardous Seas Watch
from Saturday afternoon through Sunday morning for


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