861
FXUS66 KMFR 052231
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
231 PM PST Fri Dec 5 2025

.DISCUSSION...While NW portions of our forecast area (Reedsport)
will have a couple of significantly wetter periods during the
next 7 days, the cut off between where it`s wet and where it isn`t
will be stark and bisect the CWA from NW to SE. This is because a
strong upper ridge resides well off the coast of California and
is directing a subtropical feed of Pacific moisture largely to our
north and west through the end of next week. If you`re traveling
northward from northern California or SW Oregon up to Portland or
Seattle, you`ll encounter much, much wetter conditions, where
flooding is a distinct possibility, especially heading into the
middle of next week. Now, that`s not to say we won`t have some
wet weather down here too occasionally as disturbances move over
top of the ridge, but just not to the magnitude of areas farther
north. If you`re headed south, it will largely remain dry and
mild for early December and SE portions of our area (Alturas) will
be left wondering what all the talk of rain is about.

The first disturbance is passing through our area currently and
will continue into tonight with periods of moderate rainfall
focused on the higher terrain of the Cascades and Cascades
Foothills of Douglas County. Lighter rain will occur for points
south and east. We managed to squeeze out 0.09" here at the
airport since 10 am. We`re in a bit of a break now, but do expect
a little more light rain into this evening. Breezes picking up
from the Cascades eastward in Oregon will continue this evening
with some gusts of 40-45 mph. Rainfall will taper off to drizzle
for the most part overnight with a large portion of the area dry
on Saturday (though some drizzle/light rain could linger from the
coast to Umpqua). Models do show the snow level falling to around
5000 feet in the Cascades by Saturday morning, so, if there`s
precip still around, it`s conceivable there could be a light
dusting to an inch, but that`s about it.

The next disturbance, a warm front, will move over the top and
into WA/OR late Saturday night into Sunday. This will bring a
renewed risk of steadier precipitation across N&W sections of the
CWA, once again with most, if not all, precipitation staying to
the north of the OR/CA border. We don`t currently predict any
measurable rainfall here in Medford, but there could be a
0.10-0.50 of an inch from the coast to the Umpqua Divide/Cascades.
Snow levels rise to around 7000 feet. Little or no precip is
expected southeast of Highway 97.

The Pacific fire hose will continue to wag back and forth Monday
into mid next week with models showing another warm front
shifting north of the area and snow levels rising above 8000 feet
again! The steadiest/heaviest precip will be along the
Douglas/Lane County border and the "force field" still appears to
be the OR/CA border, where precipitation will really struggle to
reach into NorCal during the stretch. There can be some minor
rises on area creeks, streams and rivers across N&W sections of
the CWA (up around Roseburg and north/west), but since they`re
running low for this time of year, we don`t expect flooding.
Again, most significant impacts from the rain will be to our
north.

Beyond that, model clusters/ensembles are coming into agreement
for late next week and confidence has increased that the upper
ridge will be the main player in West Coast weather Thu-Sat as
well. Not great news since we are heading into climatologically
the wettest time of the year. Most guidance moves the ridge into
California/SW U.S. with some scenarios even amplifying the ridge
(displacing the Pacific jet even farther north) to bring a dry,
mild period that lasts through next weekend. While the colder
scenario mentioned yesterday isn`t completely gone, less than 15%
of the ensemble membership shows this as a viable solution. CPC
8-14 day shows strong signal for above normal temps and still
shows odds leaning toward above normal precip, but this may be
from an offshore frontal system finally pushing eastward toward
the end of week 2 (after next weekend). All this got me to
thinking about snow pack, which is woefully below normal (almost
non-existent) for this time of year, and will remain that way for
the next 10 days at a minimum. In fact, looking at Mt. McLoughlin
from the valley (almost snowless) made me wonder what the latest
date in the season that the mountain hasn`t had snow on it. We
don`t have a climate record for the mountain, but at Crater Lake
(where images from the visitor`s center are also snowless), the
LATEST date in the season for a snow depth of ZERO occurred
December 26, 1976. Hopefully, this will change heading into the
end of the month and that record won`t be challenged or broken.
-Spilde


&&

.AVIATION...05/18z TAFs...Along and west of the Cascades, IFR/LIFR
ceilings are expected to continue in precipitation through much of
the day as a front makes its way across the region. Conditions may
improve slightly late this afternoon and evening, but any
improvement will be short lived with fog and low stratus likely to
form tonight.

East of the Cascades, VFR conditions will be the predominate
condition, however the higher terrain could end up partly obscured
in showers and lower ceilings art times. Stronger winds aloft could
result in some turbulence along and east of the Cascades.

Snow levels will remain higher between 8000-10000 feet.
-Petrucelli/BPN


&&

.MARINE...Updated 200 PM PST Friday, December 5, 2025...West
winds behind the front today will transition to the south Saturday
as the next system approaches the area. Steep seas will continue
due to residual wind-driven waves, then steep seas will build
further Saturday due to increasing northwest swell. After a brief
period of improved conditions Saturday night, gusty south winds
and steep seas return Sunday, especially north of Cape Blanco.
Conditions remain unsettled through the first part of next week,
with several fronts bringing periods of gusty south winds and a
likelihood of high and steep seas. -BPN


&&

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

CA...None.

PACIFIC COASTAL WATERS...Small Craft Advisory until 4 PM PST Saturday
     for PZZ350-356-370-376.

&&

$$

MAS/BPN