341
FXUS66 KMFR 130420
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
920 PM PDT Sat Sep 12 2026

...Updated the Aviation and Marine Sections...

.AVIATION...13/00Z TAFs...Isolated showers will continue across
southern Oregon this evening. Showers then linger in southwest
Oregon from the coast to the Cascades through Sunday morning, except
in Douglas County (including Roseburg) through the afternoon.
This will result in a mix of conditions, with mainly VFR. But, also
areas of coastal IFR and MVFR through the morning, and local
mountain obscuration. Coastal conditions are expected to improve to
VFR Sunday afternoon through much of the evening.

Additionally, gusty winds will persist this evening, strongest over
the terrain, in the Shasta Valley and east of the Cascades where
gusts of 25 to 35 kt will be common. These winds will diminish
overnight. Weaker westerly winds on Sunday afternoon will be
much closer to typically breezy levels.

&&

.MARINE...Updated 800 PM PDT Saturday, September 12, 2026...South
to southwest winds will persist through this evening before a cold
front passes through the region. Showers and isolated thunderstorms
are possible through this evening. Winds and seas are expected to
remain below advisory criteria through Sunday night. Winds turn west
to northwesterly tonight into Sunday.

A thermal trough develops late Sunday into Monday, bringing the
return of gusty winds and steep wind driven seas. Conditions
hazardous to small craft are likely to return south of Cape Blanco
by early Monday morning and persist through at least Wednesday
evening.

&&

.PREV DISCUSSION... /Issued 1255 PM PDT Sat Sep 12 2026/

KEY MESSAGES...

* Light rain showers will spread across most of the area this
  afternoon and evening, with isolated thunderstorms possible
  along the coast and over northern Lake and Klamath counties.

* Gusty winds are expected in the Scott and Shasta Valleys as well
  as across the East Side.

* Temperatures Sunday will cool to around 15 degrees below normal
  for this time of year.

* Warm and dry conditions return Monday and persist through the
  rest of the week, with temperatures peaking around 5 to 10
  degrees above normal by Thursday/Friday.

DISCUSSION...A line of showers has moved onshore this morning,
marking the leading edge of the approaching front. Showers will
overspread much of the area this afternoon and evening, before
tapering off overnight. Rainfall amounts will be light, with only
about a quarter of an inch expected along the coast and the
northern Cascades, and less than a tenth of an inch elsewhere.
Some locations, particularly in northern California, the East
Side, and the Rogue Valley, may only get a hundredth of an inch,
or may not measure at all. An isolated thunderstorm or two is
possible along the coast and over northern portions of the East
Side today, but chances for those remain below 20 percent.

Temperatures today are trending about 10 degrees below normal fro
this time of year, and will cool further to about 15 degrees below
normal for Sunday. Another round of frost /freeze is possible for
the populated areas of the East Side Sunday night into Monday
morning.

Gusty winds will accompany the front today, especially in the
Shasta and Scott valleys and across the East Side and northeastern
California (Modoc). Wind gusts in these areas will mostly be in
the 25-35 mph range, with gusts approaching 40 mph possible over
terrain in Lake and Modoc counties. Increasing humidity will
prevent critical fire weather conditions, but these gusty winds
moving over areas of potentially dry fuels is enough to emphasize
fire weather concerns.

After a cool, mostly dry Sunday with lighter, but still breezy
winds, a warming and drying trend begins Monday as the overhead
trough weakens for the first half of the week, then high pressure
rebuilds over southern Oregon and far northern California mid to
late in the week. Near normal temperatures are expected Monday
and Tuesday, followed by high temperatures of 5 to 10 degrees
above normal for the rest of the work week.

&&

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

CA...None.

PACIFIC COASTAL WATERS...None.

&&

$$