textproduct: Medford

Updated AVIATION Discussion

AVIATION...15/06Z TAFs

VFR conditions prevail across the region with the earlier afternoon convection winding down. Showers linger east of the Cascades and north of the OR/CA border, and an isolated thunderstorms is possible through around midnight. Overall activity will diminish late tonight. Meanwhile, IFR conditions in marine stratus have returned to the immediate coast north of Cape Blanco and are expected to persist into Wednesday morning.

VFR conditions are expected to prevail through the TAF period for inland locations. Smoke from the East Evans Creek Fire could drift into the Rogue Valley tonight, and if thick enough, could bring a period of MVFR visibilities through the morning, improving in the afternoon. Additionally, another round of showers/thunderstorms is expected Wednesday afternoon/evening, this time focused along/east of the Cascades, primarily north of Klamath Falls.

PREV DISCUSSION

/Issued 544 PM PDT Tue Jul 14 2026/

DISCUSSION...Lightning strikes have already been observed in Modoc and eastern Siskiyou counties this afternoon, lining up with guidance that expected pulse thunderstorms to continue into the evening. The highest chances for activity (20-30%) are present for Modoc, Lake, and eastern Siskiyou and Klamath counties. Lower chances (10-20%) cover western Siskiyou and Klamath as well as southeast Jackson counties. Some model runs indicate isolated activity continuing into nighttime hours, but this is not generally expected. As we've seen from recent days of thunderstorm activity, a significant outflow boundary may cause unexpected activity.

With the East Evans Creek Fire continuing to burn, overnight smoke accumulation is possible for parts of the Rogue Valley. While current observations show improved conditions, evening northerly breezes look to bring smoke back southward. Past accumulations from this fire have affected air quality from Central Point and Eagle Point to Ashland. Grants Pass has had periods of similarly impacted air quality, but for shorter durations. Traces of smoke may reach the Illinois Valley though mixing, but meaningful impacts are not expected at that distance. Anyone who is sensitive to poor air quality will want to consider their own condition as well as their environment as this fire continues to generate so much smoke.

South or southwest flow aloft between a Pacific trough and continental high pressure is expected through the forecast period, with some minimal and generally unimpactful shifts in the upper pattern. This will keep expectations of warm and dry conditions in place through at least the middle of next week. Lingering monsoon moisture will keep thunderstorm chances limited to northern Lake and Klamath counties as well as the Cascades north of Crater Lake on Wednesday afternoon and evening.

That cutoff low that nudges towards the area before spinning off to the north will cool west side temperatures west of the Cascades on Thursday and Friday. This cutoff will also bring a tighter pressure gradient aloft, which will bring elevated and periodically gusty winds east of the Cascades on Thursday and Friday afternoon and evening. Temperatures of 5 to 10 degrees above normal are possible over the weekend. Drier air aloft is expected for Thursday through the weekend, which will keep chances for additional precipitation out of that portion of the forecast.

For next week, the upper pattern becomes somewhat more intricate as areas of low and high pressure shift around the Pacific Ocean but this does not look to meaningfully change conditions in the area. Early indications of isolated afternoon and evening thunderstorm chances east of the Cascades are starting to develop for the beginning and middle of next week, but there's little sign of abundant activity at this point. -TAD

MARINE...Updated 145 PM PDT Tuesday, July 14, 2026...Gusty northerly winds are building steep seas south of Cape Blanco through tonight. North winds are expected to increase again of Friday. These thermal trough driven winds will be the strongest in the afternoon and evening hours and may result in small craft conditions through the weekend.

FIRE WEATHER...Modoc and eastern Siskiyou counties have already seen lightning strikes this afternoon, verifying that the potential for thunderstorm activity into the evening is present. The highest chances for activity (20-30%) are in those areas as well as across Lake and eastern Klamath counties. Lower chances (10-20%) are present in western Klamath, western Siskiyou, and southeast Jackson counties. Some models indicate stray activity continuing into nighttime hours, but this is not generally expected.

Chances for thunderstorms decrease on Wednesday, with slight chances (10-20%) limited to northern Lake and Klamath counties and the Cascades north of Crater Lake. By Thursday, drier air aloft eliminates thunderstorm chances through the weekend. Elevated fire weather concerns for winds and low RHs are present for Thursday and Friday as gusty winds may develop across the east side while daytime RHs are critically low. For now these forecast winds do not reach Red Flag Warning thresholds, but that may change as details become clearer.

Normal diurnal winds return, with warm and dry conditions continuing through the weekend. Southerly or southwesterly flow aloft looks to continue early next week, indicating the possibility of additional isolated thunderstorm activity. While these chances have generally been east of the Cascades, a more accurate area has been harder to describe. Signals for significant thunderstorm activity are not currently in the forecast, but that may change as details improve.

MFR WATCHES/WARNINGS/ADVISORIES

OR...CA...None.

PACIFIC COASTAL WATERS...Small Craft Advisory until 2 AM PDT Thursday for PZZ356-376.