textproduct: Medford

DISCUSSION

Updated aviation discussion.

AVIATION...18/18Z TAFs

Onshore fflow near the coast led to low ceilings, some fog and drizzle at the beaches and at North Bend this morning. These ceilings should erode in the next few hours becoming VFR this afternoon. Low-level flow will become offshore again tonight, but there could be a period of IFR/LIFR again with temps dropping quickly after sunset. These could then dissipate by early Monday morning.

Meanwhile, status quo inland with LIFR fog/low clouds persisting in the Umpqua Basin (Roseburg) and portions of the Rogue/Illinois valleys (especially Grants Pass/Cave Junction). These will erode this afternoon, breaking for a couple of hours in most places before returning this evening and lasting overnight into Monday morning.

Around Medford, fog has been developing out around the Table Rocks and briefly impacting the terminal toward morning. So have gone with persistence allowing for a brief period of IFR/LIFR visbility 14-17Z.

.Updated AVIATION discussion for 12Z TAFs

DISCUSSION...

Some high clouds are starting to move over the region with fog in the usual spots over Grants Pass in the Illinois Valley and Roseburg in the Umpqua Valley. There has also been a pretty strong coastal trapped wind reversal with stratus surging up the coast. We usually see this pattern in the summer, although it can happen from time to time in the winter.

In any case, the ridge over the Pacific will remain in place with some light easterly flow over the mountains and ridge tops. It should be another abnormally warm day across the forecast area as highs push in the upper 50's in some of the valleys and perhaps 60's along the coast if the stratus is able to erode from the east winds later this afternoon.

It will likely be a rinse and repeat with more fog and freezing fog later tonight likely around Grants Pass and Roseburg again.

This 500 mb ridge will remain in place through Monday with more abnormally warm temperatures and overnight valley fog, although things begin to gradually change into next week. Ensembles show the 500 mb ridge weakening in strength around Tuesday into Wednesday. Although that won't have wholesale changes in the forecast, we should see humidities trend higher and perhaps slightly cooler temperatures.

Then, a low chance of precipitation enters the forecast around Thursday and Thursday evening. A few ensemble members are bringing precipitation to areas west of the Cascades. The chances aren't great with only a 5 to perhaps 10% chance. Those chances increase slightly into Friday as the flow becomes more zonal. The ECMWF ensemble doesn't show a clear trough building to our west in the Pacific, so confidence isn't great for a lot of precipitation for our region. There was a small set(~10%) of ensembles that still keep our region dry through January, which wouldn't be great.

On the positive side of things, the Climate Prediction Center is predicting a higher chance for above normal precipitation for the end of January. This definitely showed up in the ensembles for areas to our north like the state of Washington, just not sure if all that precipitation will make it this far south.

-Smith

AVIATION...18/12Z TAFs...Southerly flow is keeping marine fog over North Bend, while fog has also has settled into the Umpqua Valley and Grants Pass this morning. Fog is unlikely to settle into the Medford area, although a brief period of patchy fog is possible early this morning. Both coastal and valley fog look to clear early in the afternoon, with valley fog forecast to return tonight. An expected wind reversal to offshore flow would prevent coastal fog from returning. -TAD

MARINE...Updated 200 AM PST Sunday, January 18, 2026....Seas remain below Advisory level through the weekend. Northerly winds look to increase on Monday, which may build localized areas of steep seas in outer waters. Winds look to ease into Tuesday and Wednesday. Active weather may return at the end of the upcoming week. -TAD

MFR WATCHES/WARNINGS/ADVISORIES

OR...Air Stagnation Advisory until 10 AM PST Tuesday for ORZ023-024- 026-029>031.

Freezing Fog Advisory until 10 AM PST this morning for ORZ024.

CA...None.

PACIFIC COASTAL WATERS...None.