textproduct: Medford

DISCUSSION

Updated aviation discussion.

AVIATION...16/18Z TAFs

Instability on the back side of an upper trough is leading to isolated showers, mainly over terrain late this morning (with areas of MVFR ceilings/higher terrain obscuration). These showers will linger into this afternoon (and they could be in the vicinity of Roseburg and/or Medford), but the atmosphere should stabilize with cumulus spreading out and flattening as the trough pushes farther to the east. With high pressure building in tonight, we expect mostly clear skies (VFR). Patchy fog could develop in the valleys west of the Cascades, particularly the Umpqua Valley (and perhaps at Roseburg) for a few hours early Friday morning. VFR prevails elsewhere and should persist then Friday afternoon. -Spilde

.Updated AVIATION discussion for 12Z TAFs

DISCUSSION...Showers are continuing to move over Douglas County early this morning, but activity elsewhere is nearly absent. Cool overnight lows are being observed across the area, with west side valleys starting the day off in the low to mid 30s while areas to the east are staying in the low to mid 20s. Daytime highs today look to remain below seasonal norms, with those last showers trailing off into the afternoon as the low pressure system moves farther east. Lingering cold air will bring another round of cool overnight lows tonight into Friday morning. A Freeze Warning is in place for the Rogue, Applegate, Illinois, and parts of the Klamath River Valley for early Friday morning. Frosty conditions may be possible in the Umpqua Valley, as that valley runs a little warmer.

A more stable pattern looks to guide conditions on Friday and Saturday, bringing a period of warm daytime highs and dry conditions. Saturday is forecast to be the warmest day of this period. Coastal areas may reach the low 60s, while west side valleys have forecast highs in the low 70s. To the east, expected temperatures in valleys and basins are on the mid to high 60s.

A low pressure system approaches the area on Sunday, but its modeled behavior seems to change from one run to the next. Current deterministic guidance limits precipitation to coastal areas on Sunday, and even that is uncertain. Ensembles for both ECMWF and GFS models have 50-60% chances for rainfall at North Bend on Sunday, with chances decreasing farther inland. The low dips farther south before hovering off the northern California coast. At this point, southerly flow could bring showers focused on Curry and southern Siskiyou counties. Snow levels of 5000-6000 feet at this point would allow for some mountain snow in western Siskiyou County, but widespread winter impacts look unlikely in this pattern. The modeled low moves inland over Tuesday and Wednesday, allowing for widespread showers.

Overall, nothing in this system's forecast behavior looks especially threatening, but this is a very preliminary impression. Chances of winds exceeding 35 mph (a speed safely below Advisory thresholds) are minimal in NBM probabilistic guidance, topping out at 20-40% over the Warner Mountains in Modoc County and 10-20% over some other east side peaks through Sunday and Monday. Southerly flow can favor gusty winds developing in the Shasta Valley and over nearby terrain, but models struggle with that level of detail this far out. Forecast snow levels stay in the 5000-6000 foot range. Curry County, western Siskiyou County, and the Mount Shasta region could see 1 to 1.5 inches of rainfall in this timeframe. But to repeat, expectations for this system could change as models get a better hold of its potential.

Past Wednesday, deterministic imagery starts to diverge. Meteogram guidance shows some expectation of a warm, dry period towards the end of next week. -TAD

AVIATION...16/12Z TAFs...Except for some MVFR ceilings hanging over Roseburg, VFR levels continue to start the TAF period. A stable pattern will help to break up lingering cloud cover through the day. Gusty winds develop over elevated terrain, especially east of the Cascades, this morning and afternoon before easing into the evening. Guidance suggests a slight chance for fog to develop in the Umpqua Valley near the end of the TAF period. -TAD

MARINE...Updated 200 AM PDT Thursday, April 16, 2026...Gusty northwest winds and steep seas in all waters persist into this afternoon. Winds ease some this evening, but a weak thermal trough will maintain gusty north winds south of Cape Blanco and steep seas south of Ophir into early Saturday morning. Active weather returns late this weekend into next week. Gusty southerly winds and marine showers are possible on Sunday and showers may continue into the week.

MFR WATCHES/WARNINGS/ADVISORIES

OR...Freeze Warning from midnight tonight to 11 AM PDT Friday for ORZ024-026.

Frost Advisory from midnight tonight to 11 AM PDT Friday for ORZ021-023.

CA...Freeze Warning from midnight tonight to 11 AM PDT Friday for CAZ080.

PACIFIC COASTAL WATERS...Small Craft Advisory until 5 PM PDT this afternoon for PZZ350-356-370-376.