textproduct: Medford

KEY MESSAGES

* Low impact weather expected this weekend and through at least Thursday. Inland temperatures will generally be a few to several degrees above normal (though as much as a dozen degrees), with late day breezes at or slightly below typical strength.

* Also, coastal stratus and patchy fog mainly during the night and morning hours, extending into the central portion of the Umpqua Valley in the early mornings.

* A frontal passage is possible late in the week. It would at least bring stronger breezes to the east side, but could be strong enough to bring shower and thunderstorm chances to southern Oregon and northern California.

DISCUSSION.

A ridge will build across the area this weekend. This is producing night and morning valley inversions with marine stratus extending into coastal valleys. These low clouds will be stubborn to clear at the coast, especially during Sunday. But, will gradually dissipate in the Umpqua Valley by the afternoon, and also be slowest to develop in the overnight hours in the Roseburg area.

Besides the stratus, there will be variable amounts of mainly thin high clouds over the area. This is the result of a change to a seasonable pattern of westerly flow aloft while a series of disturbances track into western Canada. The main characteristic through much of next week will be dry and warm to very warm weather.

There will be a bit of a change on Wednesday as a slightly stronger front brings rain chances farther south...into western Washington. For our area, that is expected to result in a thicker band of high clouds, a few degrees of cooling, and a modest uptick in the strength of afternoon east side breezes.

East side winds will see a more noticeable uptick, though likely still just breezy, on Thursday and/or Friday as a broader trough over the eastern Pacific Ocean swings southeastward. Forecast uncertainty increases substantially beginning Friday. For late in the week, the 00Z operational versions of the ECMWF and GFS are both on the stronger side of their respective suites of ensemble data. This situation is well represented by the NBM with its probabilities of precipitation forecast at less than 10%. With that said, around 20% of GEFS members and around 30% of ECMWF members indicate a frontal passage either on Friday or during next weekend that would be strong enough to warrant mentionable shower chances in our area, stronger breezes, and cooling of temperatures to at least near normal levels. Lastly, of that cohort of active solutions, a few also depict an environment that would support a modest level of thunderstorm development.

MARINE...Updated 100 AM PDT Saturday, September 19, 2026

Light northerly winds and low seas will be at a minimum early this morning. North winds begin to increase today with steep seas developing south of Cape Blanco late this evening, then likely extending to Cape Arago during Sunday afternoon and evening. North winds and wind driven seas are likely to continue building to a peak Monday evening, with very steep seas and gale force gusts possible south of Gold Beach. Conditions remain near that level on Tuesday with at least brief, further slight improvement on Wednesday.

AVIATION...19/12Z TAFs

Marine low clouds and fog extending into the coastal valleys and Umpqua Valley will be the only impact to aviation through Sunday morning. A mix of IFR and MVFR low clouds is the predominant condition, with patchy fog. MVFR stratus is expected to extend from the lower Umpqua Valley into most of the remainder of the Umpqua Valley, including Roseburg/KRBG, from around 13Z through 17Z this morning. Gradual improvement is expected from mid-morning through the afternoon, though with areas of mainly MVFR ceilings persisting at the coast through the day. A similar mix of IFR and MVFR is expected to return to the same areas early this evening into Sunday morning.

Other inland areas will remain at VFR levels under clear skies through Sunday morning, with weaker than normal diurnal breezes.

MARINE...Updated 100 AM PDT Saturday, September 19, 2026

Light northerly winds and low seas will be at a minimum early this morning. North winds begin to increase today with steep seas developing south of Cape Blanco late this evening, then likely extending to Cape Arago during Sunday afternoon and evening. North winds and wind driven seas are likely to continue building to a peak Monday evening, with very steep seas and gale force gusts possible south of Gold Beach. Conditions remain near that level on Tuesday with at least brief, further slight improvement on Wednesday.

MFR WATCHES/WARNINGS/ADVISORIES

OR...CA...None.

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

Hazardous Seas Watch from Monday afternoon through Monday evening for PZZ356-376.

Small Craft Advisory from 2 PM Sunday to 11 PM PDT Monday for PZZ350-370.