800
FXUS66 KMFR 142323
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
423 PM PDT Sun Sep 14 2025

...Updated AVIATION discussion for 00Z TAFs...

.DISCUSSION...The quick front has been passing the area today and
brought most of the showers with a few thunderstorms last night.
A few leftover showers are possible this afternoon near the
Cascades. Tomorrow morning will begin with slightly cooler
temperatures west of the Cascades in the 40s and 50s, but a larger
cooldown will be seen east with some locations near freezing in
northern Klamath and Lake counties.

Through the day Monday, ridging starts to build and a warming trend
will begin. Most areas will see a 5-10 degree warm up compared to
today, and this will get temperatures back to near or slightly above
normal. A thermal trough near the coast will also bring warmer
temperatures to the area, with southern Curry County near Brookings
in for temperatures in the mid-70s and low 80s.

Tuesday will be the warmest in the period as the thermal trough
moves farther inland and the ridge is at its strongest. East winds
into the morning will also bring the RHs to the teens and low 20s
for the afternoon.

There were rain chances for the coast into Wednesday due to an
incoming cold front, but the latest changes include this staying
farther north, so the precip chances have been lowered. Newer
guidance is favoring temperatures to be warmer still on Wednesday.
However, there is a 50% chance to see 90 degrees in the Rogue
Valley, so have been upper 80s for the Rogue Valley and low 80s
for the Umpqua Basin. The next chance for precipitation could be
into Friday, but model differences are still present, so this will
be monitored.


&&

.AVIATION...15/00Z TAFs...Cumulus development continues across
northern California and southern Oregon, VFR levels persisting at
areas terminals. Skies should clear as a stable pattern sets up to
start the week. Normal diurnal winds are expected inland, with gusty
winds possible for coastal areas. -TAD

&&

.MARINE...Updated 200 PM PDT Sunday, September 14, 2025...
Northwest swell-influenced seas remain below advisory levels through
this afternoon. A thermal trough will develop later this afternoon,
bringing gusty northerly winds and steep seas south of Cape Blanco
this evening through Monday morning. Steep seas will build across
all waters from Monday morning through Tuesday morning before
conditions improve through Wednesday morning.

On Wednesday afternoon, wind-built unsettled seas are possible.
Gusty northerly winds look to build across all waters, with forecast
gusts approaching gale speeds over waters south of Cape Blanco on
Thursday. This period will be watched closely as it approaches. -
TAD/Hermansen


&&

.FIRE WEATHER...Updated 200 PM PDT Sunday, September 14, 2025...Fire
weather concerns will remain low today as a trough departs the
region today. Shower activity will gradually diminish this
afternoon, coming to an end by this evening. Behind this system, an
upper level ridge builds in and a thermal trough develops along the
coast. This will induce a period of easterly/offshore flow and bring
about a sharp warming and drying trend for the Monday-Wednesday
period. East to northeasterly winds will develop tonight into Monday
morning, but recoveries will remain on the good side. It`s not until
Monday night/Tuesday morning that recoveries really drop in to the
moderate to locally poor range. Currently, it looks like recoveries
are lowest on Tuesday morning, but as drier air spreads eastward,
more areas will see moderate to locally poor recoveries for
Wednesday morning as well. Current guidance bottoms out RH
recoveries in the 30-40% range (down to 25% for some of the higher
peaks), with winds gusting to 15-20 mph. This doesn`t quite reach
criteria for watch/warning products, and typically it needs to be at
least a few nights in a row to get the RHs to really drop low
enough. As such, we`ll be maintaining a headline for this event in
the Fire Weather Planning Forecast (FWFMFR). Meanwhile, daytime
humidities will trend lower with teens/low 20s common across the
region on Tuesday. Min RHs will also trend higher on Wednesday as
the flow becomes onshore again.

Another upper level trough will approach the region on Wednesday and
this may result in some enhanced afternoon breezes for inland areas
with temperatures trending less warm Wednesday into Thursday. There
could be another round of northeasterly winds Wednesday night into
Thursday morning, but recoveries will continue the improving trend
compared to early in the week. The approaching trough looks to stall
offshore in response to low pressure moving northward along the
California coast. This is a fairly new development in the models,
but this pattern could bring the return of thunderstorms to the
forecast by Friday. It`s far too early and there is plenty of
uncertainty in the details to pin point timing and location of
potential thunderstorms, so have left them out of the forecast for
the time being. Will see how future model runs evolve before adding
details to the forecast, but this will be a time period worth
watching. /BR-y


&&

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

PACIFIC COASTAL WATERS...Small Craft Advisory until 5 AM PDT Tuesday
     for PZZ350-356-370-376.

&&

$$