textproduct: Medford

UPDATE

Aviation Discussion Updated.

AVIATION...05/00Z TAFs

A front is approaching the area moving onshore will gradually move inland across the area tonight and Monday morning. Expect VFR conditions across the region to drop to MVFR with localized IFR in precipitation as the front passes through this evening and tonight, along with increasing areas of terrain obscuration. Freezing levels of 4000-4500 ft this afternoon will lower to 3500-4000 ft MSL behind the front. Some areas west of the Cascades may see conditions lower to IFR/LIFR in low stratus Monday morning, with the National Blend of Models showing at 25-35% chance at Medford and 20-30% chance at Roseburg. Showers are expected behind the departing front late Monday morning and afternoon. Along the coast, expect conditions to improve to VFR Monday morning, except for some local MVFR ceilings which may continue along the southern Curry coast into the afternoon. Inland, expect most areas to improve to VFR in the mid to late afternoon on Monday.

PREV DISCUSSION

/Issued 253 PM PST Sun Jan 4 2026/

DISCUSSION...A persisting upper trough will guide weather across northern California and southern Oregon into Monday. For this evening, a weak cold front will help to push another round of light to moderate precipitation across the area. Cold air behind the front will lower snow levels to 3500-4000 feet by Monday morning. With precipitation continuing through the day Monday, additional snowfall is expected for Cascades passes and Sawyers Bar Road west of Etna tonight through Monday morning. 1 to 2 inches may reach Interstate 5 at Sikiyou Summit or between Weed and Dunsmuir as well as on Highway 89 and 97. With limited snowfall, road warmth, and lingering water on road surfaces, highway snow accumulation may be limited but slippery conditions may develop where snow showers fall.

The upper trough splits on Monday, sending a cutoff low to the south. This will bring a brief pause in activity on Tuesday morning, with slight chances of isolated showers persisting. A cold front brings afternoon showers to the coast and the Cascades, then precipitation moves inland through Wednesday and Thursday. While coastal and low-lying areas will see light to moderate activity at most, snowfall over the Cascades remains a concern through midweek. Forecast amounts remain at 8 to 16 inches between 4500 and 5500 feet, which would include Cascades passes and Willamette Pass. Accumulation could reach 16 to 24 inches over peaks and ridgelines. This amount of snow represents Advisory-level winter weather for the Cascades through much of Wednesday, but forecast snow levels have been trending upwards through recent model runs. While this doesn't change that snow over the Cascades looks to be the main impact of the midweek front, the timing and amounts could change. Snowfall is expected east of the Cascades as well, with 4 to 8 inches forecast for eastern Cascades foothills and 3 to 6 inches for east side terrain. Basin floors are expected to see an inch or less. West of the Cascades, the lowest forecast snow levels are up to 2500 feet and that's on Thursday morning when precipitation is clearing out. With this forecast, Interstate 5 at Siskiyou Summit would see an inch of snowfall at most and a few stray snow showers would be possible around the Mount Shasta region.

Behind the midweek front, expectations for a period of stable weather remain as activity trails off through Thursday and a Pacific ridge remains in deterministic imagery. Some GFS ensemble members show upper troughs briefly flattening the ridge. NBM guidance keeps coastal precipitation chances at 10-20% at the highest and single digit chances inland for Friday through Sunday. -TAD

MARINE...Updated 200 PM PST Sunday, January 4, 2026...With the passage of the front, winds have diminished and seas will gradually lower through tonight. Improved conditions are expected Monday into Tuesday with a mix of northwest swell and lingering fresh south swell. Another front passes Tuesday with a brief period of gusty south winds and steep seas, followed by long period swell arriving Tuesday night, and building and steepening Wednesday into Thursday. -BPN

BEACH HAZARDS/HIGH SURF...Updated 200 PM PST Sunday, January 4, 2026...Long period swell, originating from a storm along the Aleutian Islands, is forecast to arrive in the southern Oregon waters Tuesday night, then build Wednesday into Thursday. Early indications are showing the swell arriving at 3-6 feet at 20-25 seconds, which initially poses a risk for sneaker waves Tuesday night into Wednesday. Then, as the swell builds to 13-18 feet, high surf risk increases Wednesday afternoon into Thursday. It's still several days away, so we'll continue to monitor for possible beach hazard and/or high surf products. -Spilde/BPN

MFR WATCHES/WARNINGS/ADVISORIES

OR...Winter Weather Advisory until 4 PM PST Monday for ORZ027.

CA...Winter Storm Warning until 4 PM PST Monday for CAZ080-082-083.

PACIFIC COASTAL WATERS...Small Craft Advisory until 10 PM PST this evening for PZZ350-356-370-376.