textproduct: Medford

DISCUSSION

A short wave upper ridge is moving in over the region this afternoon. The low clouds and fog from earlier this morning have broken up and some areas have shed the clouds altogether. But, some stratocumulus remain and there could be isolated showers/sprinkles (mainly over the mountains) through late afternoon. Any showers inland end tonight and Tuesday, but onshore flow developing near the coast could cause an increase in cloud cover there along with a low chance (20-40%) of a little light rain (but this won't amount to much more than a hundredth here or there). With some clearing for inland areas this evening, radiational cooling overnight into Tuesday morning could lead to low clouds/fog in the valleys area wide (including over the East Side and in NorCal), so some lower/reduced visibility could impact the morning commute.

Most areas will remain dry and mild Tuesday (highs mostly in the upper 50s to low 60s), though there's some chance PoPs along the coast as an upper trough offshore approaches. Most of the rain though is likely to hold off until Tuesday night.

The upper trough and cold front will arrive in WNW flow aloft Tuesday night into Wednesday. Expect a period of widespread light to moderate precipitation to accompany the cold front with the focus along the coast and into the Cascades (amounts of 0.50-1.00 inch common, though up to 1.50 inches in areas of favored WNW- facing terrain). Expect lower amounts (0.10-0.25 inch) in the downslope areas (especially the valleys and to the immediate southeast of the Cascades/Siskiyous) with up to 0.50 inch or so in the Warners. Snow levels around 6000 feet Tuesday evening, drop to 4000-4500 feet by Wednesday evening. Most winter impacts will be confined to the higher terrain and Cascade passes. Snow amounts of 5-10 inches are expected above 5000 feet in the Cascades north of 140, highest in the vicinity of Crater Lake. In these areas, snowfall rates on Wednesday morning/afternoon remain a concern at those higher elevations. Parts of highways 62, 230, and 138 near Crater Lake and Diamond Lake may see snowfall rates of 0.5 to 1 inch per hour Wednesday morning into the afternoon with travel impacts. For this reason, we issued a Winter Weather Advisory for ORZ027 above 5000 feet from 4 am until 10 pm Wednesday. Some travel impacts are also possible over the pass on Highway 140 near Lake of the Woods, but amounts/impacts there (2-5 inches) and points southward don't warrant an advisory. While some wet snow could fall on I-5 at ~4300 ft at Siskiyou Summit too, significant impacts aren't likely with probabilities of 1" or greater of snow only ~10-15%. Expect breezy conditions to develop for most areas Wednesday afternoon, but especially over the East Side and in NorCal. Wind gusts of 30-40 mph are most likely with about a 30% chance of a wind gust to 45 mph. We aren't anticipating wind headlines with this frontal system, since mid- level flow (despite a well-mixed BL) just isn't quite strong enough (peaking at 35-40 kt).

With the trough axis shifting eastward, coverage of post-frontal showers diminishes Wednesday evening for the Rogue Valley (and southeast of the Cascades), but onshore flow keeps them going along the coast, to around the Rogue-Umpqua Divide and over to the Cascades right through Wednesday night. Back side energy could still bring some chance of showers on Thursday across NW sections, with dry weather taking hold elsewhere.

Late this week, this weekend and into early next week, models remain in agreement showing a strong upper ridge developing over the Pacific (around 140W) with the core of a strong upper jet directed to our north. The strength of this ridge and the timing of any disturbances sliding over the top of it are the main sources of uncertainty. Many outcomes keep the bulk of precipitation to our north, while others bring the possibility of light rainfall to NW sections, especially coast and Cascades. NBM PoP guidance shows slight chance to chance PoPs over NW sections of the CWA, with dry and milder conditions to the south and east. Either way, this doesn't look like a period of stormy weather coming up, but rather glancing blows from systems coming over the top. CPC forecasts continue to favor near to above normal temps and drier than normal for Week 2 (through mid-March). -Spilde

AVIATION...02/18Z TAFS

A wide range of flight conditions are occurring and will continue across the area. MVFR/IFR ceilings and visibility along the coast, in the valleys west of the Cascades, and across the East Side will improve to mainly VFR through this afternoon, but some localized areas of low flight conditions could persist longer. After mainly VFR through this afternoon and evening, expect low ceilings and fog to return to many area valleys overnight, with low flight conditions possible at all area terminals. Improvement is again expected through late Tuesday morning.

MARINE...Updated 800 PM PST Monday, March 2, 2026

Light south winds and relatively calm seas are expected through tonight. Winds increase and seas steepen Tuesday through Wednesday as a front moves through the area. Showers and low visibility are possible Tuesday through Wednesday. Steep west seas follows through the end of the week, with westerly winds becoming more northerly through later parts of the week.

MFR WATCHES/WARNINGS/ADVISORIES

OR...Winter Weather Advisory from 4 AM to 10 PM PST Wednesday for ORZ027.

CA...None.

PACIFIC COASTAL WATERS...Small Craft Advisory from 1 AM to 10 PM PST Wednesday for PZZ350-356-370-376.