textproduct: Medford

DISCUSSION

Updated aviation discussion for 06Z TAFs.

AVIATION...14/06Z TAFs

Along the coast, expect at least MVFR ceilings due to marine stratus, but also areas of IFR/LIFR, especially south of Cape Blanco overnight through Friday. The marine layer should have staying power on Friday due to enhanced onshore flow, so some areas won't clear to VFR in the afternoon. Even if it does clear for a while, stratus will return Friday evening and overnight. Roseburg, VFR at the moment, will see MVFR ceilings develop tonight (around 10-11Z), and then last through around 19Z before becoming VFR again.

Farther inland, isolated showers/thunderstorms continue this evening mainly east of Highway 97 and especially near Highways 140 and 31. These should wane overnight. We expect cumulus development Friday afternoon with isolated showers/thunderstorms again. Lightning probabilities are too low (5-15%) to include in any TAFs currently, but this may change as things develop Friday afternoon. Expect typical afternoon breezes to continue. The Fielder Mtn Fire near Rogue River may cause some smoke impacts (local MVFR visibility) at KMFR, but this will be evaluated with each TAF cycle to assess any potential visibiltiy reductons. -Spilde

PREV DISCUSSION

/Issued 628 PM PDT Thu Aug 13 2026/

DISCUSSION...Updated aviation discussion for 00Z TAFs.

AVIATION...14/00Z TAFs...

New fire along I-5 near Rogue River (Fielder Mtn Fire) may cause some smoke impacts (local MVFR visibility) at KMFR this evening. Isolated showers and thunderstorms developing in northern Klamath/Lake counties will gradually diminish through this evening. Breezy conditions all areas will ease after sunset.

Along the coast tonight, marine stratus at KOTH is MVFR at the moment, could occasionally lower to IFR overnight and persist through Friday. Brief break to VFR is possible there Friday afternoon, but should be short-lived. Expect the stratus to push inland to Roseburg with MVFR again for several hours Friday morning (10-19Z), then clearing to VFR.

Expect some cumulus development again Friday afternoon along with isolated showers/thunderstorms. Typical afternoon breezes will continue. -Spilde

PREV DISCUSSION... /Issued 142 PM PDT Thu Aug 13 2026/

KEY MESSAGES...

* Seasonably warm, dry, and breezy conditions continue to be the overall theme going forward

* Thunderstorm chances increase today continuing through Saturday and again through early parts of next week with the main risk being isolated lightning and gusty erratic winds

* Areas of smoke remain possible due to nearby wildfires

DISCUSSION...

A trough has formed over the western CONUS, and this general trough pattern will remain over the west coast for well into middle parts of next week. Beyond Wednesday, the pattern continues to show inconsistencies with the models out of phase from one another. This has resulted in some uncertainty, mainly middle to later parts of next week.

This pattern will allow for several days of thunderstorm chances. While uncertainty exists on coverage details due to the isolated nature of these potential storms, the takeaway is that we're not anticipating these to produce much--if any--rain. We are also expecting lightning to be very isolated. In fact, instability is not that great across the forecast area which further increases confidence in overall isolated storms. DCAPE values are still on the higher end in some model outputs, so any storms that happen to develop could lead to strong gusty outflows with speeds potentially around 45-55 mph. For each afternoon/early evening today through Saturday, northern parts of both Klamath and Lake counties are favored for isolated storms, but cannot rule out parts of northern California as well. We are not anticipating a Red Flag Warning at this time, but if coverage and/or lightning intensity increases we may have to reconsider this. That said, we are in peak fire season, so any lightning over these dry fuels could produce some initial attack starts, but this also depends on where the potential fires start.

One concern for tomorrow is a signal in the models keeps "flip flopping", meaning its showing up in one run but then disappearing in subsequent runs. This is for isolated thunderstorms over the Siskiyou Mountains that border California and Oregon. In the low chance this occurs, a storm could spill over into the Rogue Valley. This is something we will continue to monitor for tomorrow, but at this time that threat is very low around 5%-10%.

-Guerrero

MARINE...Updated 130 PM PDT Thursday, August 13, 2026...Winds will continue to ease today/tonight, but continue at Small Craft Advisory strength through Friday morning. Weak winds and below advisory seas are expected Friday afternoon through at least Sunday morning. North winds early next week could reach Advisory strength south of Port Orford.

MFR WATCHES/WARNINGS/ADVISORIES

OR...CA...None.

PACIFIC COASTAL WATERS...Small Craft Advisory until 11 AM PDT Friday for PZZ356-370-376.