121 
FXUS66 KMFR 040724
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
1224 AM PDT Sat Apr 4 2026

.DISCUSSION...It's a quiet night in southern Oregon and far
northern California, with mostly clear skies and light winds under
high pressure. Some areas of fog are possible in some of the West
Side valleys early this morning, but with less moisture in the
prevailing air mass, coverage should not be nearly as extensive as
yesterday morning, and will likely remain confined to the Umpqua
and Illinois valleys. 

A thermal trough will remain in place along the coast through 
today with light offshore flow. This should keep the mid slopes 
and some of the higher terrain warmer and drier overnight.

Temperatures will continue to warm today and Sunday with many 
valleys seeing mid to upper 70's west of the Cascades with areas 
farther east in the upper 60's to perhaps lower 70's on Sunday. 
Even with this warm up, we'll still be a few degrees short of high
temperature records for April 4th and 5th.

The main weather feature Monday will be the chance of showers and
thunderstorms over the higher Cascades and perhaps some lower
elevations east and west of the Cascades. Looking at the ECMWF
ensemble, it looks like every member is putting down some QPF
somewhere across the region, although that could be showers
instead of a thunderstorm. Model soundings show the highest 
amount of convective available potential energy(CAPE) in the high 
Cascades in Crater Lake with some of that energy around 
-10C to -20C. Therefore, it seems reasonable there could be some 
cloud to cloud or cloud to ground lightning Monday afternoon near 
Crater Lake.

The synoptic pattern continues to evolve by Tuesday as a cut low off
the California coastline lingers while an open trough and front 
pass just to our north. Tuesday is looking drier, then rain
chances increase Wednesday into Thursday as the closed low 
finally moves onshore with the arrival of a second trough from the
northwest. This still keeps most of the precipitation chances 
over northern California, but some could sneak north across the 
state line. With mostly light, showery precipitation, and snow
levels remaining well above 5000 ft, little to no impacts are
expected. 

&&

.AVIATION...04/12Z TAFs...VFR conditions will persist through the
TAF period for most the area. The exception is that conditions 
are expected to locally lower with areas of IFR/LIFR along the 
coast (KOTH) and in the Umpqua Basin (KRBG) early this morning. 
Any lower flight conditions should clear to VFR by mid to late 
morning. 

Also, gusty north winds will continue through the day for much of
the coast and over the coastal waters. 

&&

.MARINE...Updated 1200 AM PDT Saturday, April 4, 2026...Gusty 
north winds and steep seas continue through tonight, then once the
thermal trough weakens, relatively calm conditions are expected 
through early next week. However, another thermal trough develops 
bringing another round of strong north winds and steep seas by 
Tuesday afternoon and strengthening through at least Wednesday 
night.


&&

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

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

&&

$$