365
FXUS66 KMFR 271758
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
958 AM PST Thu Nov 27 2025

.DISCUSSION...Updated aviation discussion.


&&

.AVIATION...27/18z TAFs...A cold front will move onshore in the
next couple of hours. Soundings indicate some potential for low-
level wind shear near the coast (North Bend) for the next hour or so
as surface winds are from the SE and winds just off the ground
(about 1000 ft AGL) are near 40kt from the SSW. With the front
moving onshore, expect winds to shift and become gusty along the
coast after 19z. Meanwhile, low-level moisture will bring MVFR
ceilings, higher terrain obscuration) and scattered light showers
from the coast inland to the coast range mountains,
the Illinois/Umpqua valleys, and over to the Cascades. There`s a
less than 10% chance of any measurable precip making it farther
south and east than that (including here in Medford). Most inland
areas will be VFR through this evening.

Later tonight, light showers and MVFR will persist along the coast.
Some inland areas could also see brief showers, but things should
stabilize a bit overnight and this may result in IFR/LIFR
ceilings/fog in the Umpqua/Rogue/Illinois and lower Klamath basins.
These conditions likely last through late morning, but could
become VFR 18-20Z. -Spilde


&&

.PREV DISCUSSION... /Issued 356 AM PST Thu Nov 27 2025/

..Updated AVIATION discussion for 12Z TAFs...

DISCUSSION...Fog is starting to fill the Umpqua Valley, with
tripcheck cameras showing impaired visibility at multiple spots on
Interstate 5, especially at Canyon Mountain. Cameras also show
some development over western Grants Pass. Satellite imagery is
indicating fog developing in the Illinois Valley and parts of the
Klamath River Valley. Working against the fog is an approaching
cold front that looks to bring showers to Coos, Curry, Josephine,
and Douglas counties early this morning. While amounts will be
light, the combination of rainfall in those counties and southerly
winds across the area may be enough to break up west side valley
fog. For other areas, today looks to remain mild and uneventful.

Please see the previous discussion below for more details on the
short- and long-term forecast. -TAD

AVIATION...27/12z TAFs...An approaching cold front is already
bringing showers to the Oregon coast, although levels remain at VFR
at North Bend. Fog in the Umpqua Valley has caused LIFR levels early
this morning, but mixing and rainfall from the front should help to
clear the fog. Activity from the front looks to stay over Coos,
Curry, Josephine, and Douglas counties. Levels should generally stay
at VFR or MVFR as the front moves over these areas today, but
locally lower ceilings and visibilities are possible and passing
showers or low ceilings may obscure terrain.

Other areas look to stay at VFR levels through the daytime. Low
ceilings or fog may return to low-lying areas tonight into early
Friday morning, although guidance only expects development in the
Umpqua Valley. -TAD

MARINE...Updated 200 PM PST Wednesday, November 26, 2025...
Southerly winds increase again tonight into Thursday morning
as a cold front passes through the region. Meanwhile, a heavy
northwest swell will move into the waters late Thursday morning and
afternoon. These conditions will bring the return of steep seas to
all waters, with very steep seas north of Cape Blanco due to a mix
of wind waves and the heavy swell.

Conditions improve late Friday as winds turn northerly then persist
through the weekend and into early next week. Conditions hazardous
to small craft could return south of Cape Blanco on Sunday.
Meanwhile, a long period swell (peaking around 6 to 9 ft at 16 to 19
seconds) builds in the waters early next week, which could maintain
advisory level conditions into early next week.

PREV DISCUSSION... /Issued 239 PM PST Wed Nov 26 2025/

DISCUSSION...A warm front has lifted north with high pressure and
mostly clear skies across the area this afternoon. A low pressure
center will near the coast of Washington and northern Oregon
tonight with a cold front moving onshore by Thursday morning. This
front will be weaken as it moves inland. Models and ensembles
continue to support moderate to high (60-100%) chances for light
rain along the coast, inland into the coastal mountains, Umpqua
Valley, southwest Josephine County and into the south- central
Oregon Cascades. Low chances (10-30%) for rain are also expected
for the Rogue Valley in Jackson County, northeast Josephine
County, far western Siskiyou County, and far northern Klamath
County. East of the Cascades, expect dry but breezy to gusty
conditions on Thursday.

Then, Thursday night the low moves inland north of the area. This
will bring onshore flow and  a trough over the area. Ensembles
show chances for rain showers continuing along the coast (70-95%)
along the coast and inland across Josephine (30-60% chance),
Douglas County (70-90% chance) and across the south- central
Cascades (35-75%). Low chances for showers (10-40%) are expected
across Jackson, far western Siskiyou and northern Klamath
counties as well. Precipitation will be light and snow levels
will be high, around 6000-7500 feet on Thursday, lowering slightly
around 5500-6000 feet Thursday night. So expect little if any
snow is expected, except for higher peaks in the south-central
Oregon Cascades. Light scattered showers linger into Friday across
northwest portions of the CWA, before tapering off during the
afternoon.

On Saturday, models show a building high pressure ridge offshore
with a shortwave trough moving down from the north late Saturday
and Saturday night. This trough may be far enough east that little
if any showers will develop over the area. The National Blend of
Models is showing low chances (10-30%) for light rain and higher
mountain snow across the area during this period Saturday
afternoon and Saturday night. We will continue to monitor and
update the forecast as confidence increases.

Sunday and Monday, models are trending towards a high pressure
ridge building inland and a longwave trough east of the area. This
will likely bring stable and dry weather to the area with cool to
cold overnight/morning temperatures. Then, Monday night and
Tuesday, ensembles support a shortwave trough moving down into the
region from the northwest, bringing chances for light rain and
mountain snow. However, there remains significant variability in
the details for this period.

&&

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

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

Hazardous Seas Warning until 4 AM PST Friday for PZZ350-370.

&&

$$

MAS/MAS/MAS