419
FXUS66 KMFR 301723
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
1023 AM PDT Wed Sep 30 2026

.Updated AVIATION Discussion...

&&

.AVIATION...30/18Z TAFs...A mix of MVFR/IFR ceilings from marine
stratus persist in the Umpqua/Coquille Basins and over the marine
waters, with VFR prevailing for inland locations. Marine stratus is
eroding and will clear for all areas between 18z-20z with VFR
prevailing thereafter. VFR will prevail through the TAF period for
just about all areas. Offshore flow should keep the marine layer
from returning tonight. Couldn`t rule out some patchy LIFR
conditions in the deeper river valleys along the coast/Umpqua Basin,
but terminals should remain VFR through the TAF period.

&&

.PREV DISCUSSION... /Issued 441 AM PDT Wed Sep 30 2026/

KEY MESSAGES...

* Warm temperatures and dry conditions continue through the
  forecast period.

* Temperatures look to peak over the weekend, with forecast
  daytime highs staying 10 to 15 degrees above normal.

* An upper disturbance may bring nocturnal thunderstorm chances to
  northern California on Sunday night into early Monday morning,
  but chances are currently in the single digits.

DISCUSSION...Northwest flow aloft as an upper level Pacific ridge
approaches the continental United States is bringing a decent marine
push early this morning. Marine stratus has settled along the coast
north of Cape Blanco and into the Umpqua Valley as well as over
Brookings. This layer looks to clear out early in the afternoon.
With the ridge creeping closer today, temperatures may rise by a
couple degrees from Tuesday`s highs but overall similar conditions
are expected.

By Thursday and Friday, high pressure moves inland over the
southwest United States. Additional warming will bring temperatures
5 to 10 degrees above normal for the area, with northern California
seeing the ~10 degree increases while Douglas and northern portions
of Lake and Klamath counties are more likely to be in the ~5 degree
above average range.

On Saturday and Sunday, temperatures rise into the 10 to 15 degree
above average range. Over the weekend, coastal areas are expected to
be in the high 70s. East side areas and Douglas County are forecast
to be in the low to mid 80s. Other west side valleys look to be in
the high 80s to low 90s while parts of the Klamath River Valley may
approach 100 degrees. Weekend daytime highs may tie or break
existing records for some parts of the CWA. Easterly flow overnight
may pose fire weather concerns as recoveries over area peaks and
ridgelines may be more moderate, with possible localized poor
recoveries over terrain in Siskiyou and Modoc counties. Models are
also starting to show very slight chances for isolated nocturnal
thunderstorm activity over northern California on Sunday night into
Monday morning. Those chances are in the single digits right now,
but the possibility is worth acknowledging.

Beyond the weekend, long-term guidance shows some possibility of a
slow and steady decrease in daytime warmth. With that said,
temperatures could stay above seasonal norms through much of next
week. -TAD

MARINE...Updated 300 AM PDT Wednesday, September 29, 2026...
West-northwest swell dominated seas will transition to wind wave
dominated seas today as the thermal trough restrengthens and expands
northward along the southern Oregon coast. Gusty north winds and
steep wind-driven seas then continue into Friday before weakening as
the thermal trough moves inland this weekend.

&&

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

PACIFIC COASTAL WATERS...Small Craft Advisory until 11 PM PDT Friday
     for PZZ356-376.

&&

$$