713
FXUS66 KMFR 131204
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
504 AM PDT Sun Sep 13 2026

.KEY MESSAGES...

* Light showers continue over Coos and Douglas counties early this
  morning. Showers look to dissipate by the afternoon, with cool
  daytime highs forecast across the area.

* Warm temperatures and dry conditions are expected for the week
  ahead, with daytime highs 5 to 10 degrees above normal possible
  by Thursday and Friday.

* A cutoff low may bring periods of gusty westerly winds to
  western Cascades foothills and up to Crater Lake and Diamond
  Lake on Wednesday or Thursday. Isolated thunderstorms may also
  be possible.

&&

.DISCUSSION...Most areas (excepting Siskiyou County) saw at least
some rainfall through the day on Saturday, although amounts for
inland areas were generally measured in the hundreths of an inch.
Gusty winds over east side terrain generally reached 30-40 mph, with
one observation from Coffee Pot Flat reaching 57 mph. Activity has
decreased early this morning, with winds back to normal levels
across the area and a few light showers trailing over Coos, Curry,
and Douglas counties. For today, cool temperatures are expected on
either side of the Cascades. Some parts of Lake County may be 20
degrees cooler than they were on Saturday, while other east side
areas may see 10 to 15 degrees of cooling. Rain showers will
dissipate as the day passes.

For east side areas, overnight lows for Sunday night into Monday
morning are worth mentioning. Temperatures in the low to mid 30s are
expected for Lake and Klamath counties, with mid to high 30s in
Modoc and eastern Siskiyou counties. For the latter areas,
conditions are near Frost Advisory thresholds but confidence in
meeting those thresholds is not present. A small shift in
expectations may support a product being issued later today.
Regardless, any especially sensitive plans and animals may require
additional attention given that tonight will be chilly and local
areas may reach frost conditions.

An overall uneventful week remains in the forecast, with warm and
dry conditions expected across the area. Current guidance has
temperatures peaking west of the Cascades on Thursday and Friday
while the east side looks to be warmest on Friday and Saturday. One
feature of interest will be a shortwave trough that may develop a
cutoff low as it approaches. For most areas, this feature will have
little to no impact. However, this feature could bring some fire
weather concerns. Its current path would bring gusty winds to the
western Cascades foothills up to the peaks. Current guidance keeps
humidities out of critical ranges, and upslope flow of September
rain showers may have helped these foothills get some additional
moisture. A Warning product wouldn`t be needed with expected
conditions, but these winds are unusual enough to deserve
acknowledgement. Additionally, deterministic imagery is showing
isolated thunderstorms may be possible in the afternoon and evening
of Wednesday and Thursday. With the atmosphere in that timeframe
looking dry, those thunderstorm chances are looking very slight.
Overall, this shortwave trough/cutoff low does not currently look
overly threatening, but its path and characteristics are worth
paying attention to as midweek approaches. -TAD


&&

.AVIATION...13/12Z TAFs...VFR levels continue for most parts of
northern California and southern Oregon early this morning, with
passing showers bringing periodic MVFR conditions over Coos and
Douglas counties. Very light showers may continue over these areas
through the afternoon, then VFR levels will be present across the
area through the rest of the TAF period. -TAD

&&

.MARINE...Updated 200 AM PDT Sunday, September 13, 2026...Southerly
winds and below advisory seas continue today. A thermal trough looks
to develop early Monday morning, with gusty northerly winds building
steep seas south of Cape Blanco by Monday afternoon. This thermal
trough looks to have its strongest winds in the afternoon and
evening of Monday and Tuesday. Current guidance shows wind gusts
south of Gold Beach increasing to near gale strength in these
periods, although not currently close enough for a watch/warning.
Any further increases to forecast winds may require an additional
product to address.

Wind gust speeds decrease on Wednesday but areal coverage increases,
which may build steep seas north of Cape Blanco. Winds and seas
looks to ease on Thursday. -TAD


&&

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

PACIFIC COASTAL WATERS...Small Craft Advisory from 2 PM Monday to 11
     PM PDT Tuesday for PZZ356-376.

&&

$$