869
FXUS66 KMFR 162120
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
220 PM PDT Wed Apr 16 2025

.DISCUSSION...Satellite image shows clear skies over most of the
forecast area. The exception is for a few cumulus in southern
Siskiyou and Modoc County. All indications suggest the best chance
for isolated storms will remain south of the forecast area, and
satellite image supports this idea with convective clouds along
with a couple of lightning strikes in central Lassen County.

An upper trough (insider slider) will drop south into the area this
evening and tonight. It will remain dry, but guidance shows winds
could be elevated and breezy east of the Cascades.

The upper trough will move east of the area Thursday ushering in a
cooler and drier air mass, with moderate to occasionally strong
winds east of the Cascades Thursday afternoon into Thursday evening.
Breezy winds are also likely for the westside valleys Thursday
afternoon into early Thursday evening.

Friday will be dry with afternoon temperatures warming up some, and
will be above seasonal norms as the upper trough from Thursday digs
south and bringing a dry east to northeast flow over the area. We
can expect gusty afternoon and early evening breezes east of the
Cascades and the higher terrain west of the Cascades. Also gusty
breezes are likely for the interior westside valleys. However, winds
are not expected to be as strong as upper ridging builds in and
winds aloft become weaker.

Saturday, a weak upper trough will move into the area, but the main
effect from this will be cooler afternoon temperatures, and more
cloud cover. The operational models hint at some light precipitation
along the coast and north ofthe Umpqua Divide Saturday. Some of the
ECMWF individual ensemble members show very light (basically trace
amounts) of precipitation, and all of the GFS individual ensemble
members show a dry solution.

Weak troughiness remains over the area Sunday into early next week.
It`s likely to remain dry, but it will be cooler with gusty breezes
in the afternoon. -Petrucelli


&&

.AVIATION...16/18Z TAFs...VFR conditions will prevail through the
TAF period for most locations. Gusty northerly winds are expected
along the coast this afternoon, including at North Bend (~30kt).
Expect the typical diurnal increase in north to northwest breezes
(~10-20kt) for inland locations this afternoon as well.

Marine layer clouds will mostly dissipate or at least be off the
immediate coast this afternoon, but guidance is showing potential
for MVFR ceilings to move back in early this evening (~01Z). Even
so, with low-level flow turning offshore, stratus may not last all
night at North Bend. The most likely scenario is MVFR stratus
breaking up to SCT and pushing offshore after 09Z. Just inland, in
the Coquille Valley, ceilings may get trapped for a while, so MVFR
cigs are likely to last there the longest. VFR prevails elsewhere
tonight into Thursday morning with winds subsiding. -Spilde


&&

.MARINE...Updated 230 PM Wednesday, April 16th...A thermal trough
will bring gusty northerly winds and steep to very steep seas to the
coastal waters, with the strongest winds and steepest seas south of
Cape Blanco through late tonight/early Thursday morning. Very steep
seas are possible as far north as Cape Arago with gale gusts
possible from Gold Beach southward and within 30 NM from shore
through this evening. The thermal trough will vary in strength
easing back a bit Thursday into Friday, but with conditions at least
remaining hazardous to small craft. It looks like the thermal trough
will re-strengthen this weekend with strong northerlies again (and a
return of possible gale force winds south of Cape Blanco) along with
steep to very steep seas. -Spilde/BR-y


&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...CA...None.

PACIFIC COASTAL WATERS...Hazardous Seas Warning until 8 AM PDT
     Thursday for PZZ350-356-370-376.

Small Craft Advisory until 8 AM PDT Thursday for PZZ350-370.

&&

$$