534
FXUS66 KMFR 300555
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
1055 PM PDT Tue Sep 29 2026

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

.AVIATION...30/06Z TAFs...IFR/LIFR marine stratus/fog is expected to
continue developing along the coast north of Cape Blanco overnight
into Wednesday morning. Marine clouds will also spread into the
Umpqua Valley late tonight into Wednesday morning, including
Roseburg from around 13Z through 17Z. All areas of lower flight
conditions should clear to VFR around midday or early afternoon.

Otherwise and elsewhere, VFR conditions will prevail through
Wednesday evening. High clouds will increase late Wednesday night
while low level northeast winds are expected to limit stratus north
of Cape Blanco to patchy coverage.

&&

.MARINE...Updated 800 PM PDT Tuesday, September 29, 2026...
West-northwest swell dominated seas will transition to wind wave
dominated seas Wednesday 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.

&&

.PREV DISCUSSION... /Issued 131 PM PDT Tue Sep 29 2026/

KEY MESSAGES...

* Low impact weather expected through the forecast period.

* Temperatures trend warmer through the week, peaking around 10-15
  degrees above normal over the weekend.

* Slight chance of thunderstorms east of the Cascades on Sunday.

* No signal for widespread precipitation for the next 7-10 days.

DISCUSSION...The upper level pattern will largely be ridge
dominated through the week and into the weekend. Today will be the
coolest day of the forecast period as the flow aloft remains
northwest and a weak disturbance moves through this northwest flow.
There will be a good marine push with this disturbance, so expect
some decent stratus cover over the West Side tonight into Wednesday
morning. Cloud cover will likely be most extensive along the coast
and north of the Rogue/Umpqua Divide, but guidance shows this
spilling over into the Illinois/Applegate Valleys and possibly even
here into the Rogue Valley.

High pressure will linger off the California coast through
Wednesday, then gradually shift inland Thursday and eventually
settle over the Desert Southwest by the weekend. For the remainder
of the week, our area will remain on the northern periphery of this
high pressure with zonal flow aloft. Heights will subtly build
through the week, bringing a warming trend in afternoon temperatures
starting Wednesday. High temperatures will hover around 5-10 degrees
above normal through the rest of the week, which brings mid-upper
80s for the West Side and upper 70s/low 80s for the East.

Weak low pressure approaches the area over the weekend. As this
happens, the ridge axis becomes positively tilted over the region
Saturday, and high temperatures peak over the weekend, trending
higher by around another 5 degrees. This pushes highs in the lower
90s for the West Side and mid 80s for the East. The flow aloft
becomes more southerly on Sunday, and the weak low pressure moves
overhead. This could bring a slight chance of showers/thunderstorms
to the area, most likely east of the Cascades. Current forecast
keeps this mention out of the forecast for now, but the pattern is
favorable for thunderstorm development on Sunday if it pans out.

High temperatures trend a few degrees cooler behind this weak low
pressure for the early part of next week, but the upper level ridge
rebounds quickly late Tuesday into Wednesday. Long term guidance is
showing this ridge sticking around through much of next week (week
of Oct 5th), which would maintain above normal temperatures and dry
conditions through then.

&&

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

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

&&

$$