textproduct: Medford

DISCUSSION

The main weather message the next 7 days (through next Thursday) will be one of N-NW flow aloft with a series of weak, low-impact "inside slider" weather disturbances moving through over the top of a semi-permanent upper ridge parked off the West Coast (out near 140W). The first of these disturbances is exiting the area to the east into Idaho this afternoon. There had been some lingering moisture along the coast during the morning, but light showers/drizzle associated with that have ended. High pressure shifts into the area tonight while low pressure near 40N 135W pushes southeastward well off the NorCal coast. Strengthening inversions should lead to more extensive coverage of valley fog/freezing fog late tonight and Saturday morning.

Another similar upper trough is expected to swing through from the northwest Saturday night into early Sunday. Current model guidance has shown a slight increase in PoPs and expanded areal coverage of potential precip a bit farther south compared to earlier runs. So, we have made that adjustment in the going forecast. This means there is about a 30-50% chance of light snow over the higher Cascades southeastward to the Warner Mountains after about 7 pm PST Saturday night until around sunrise Sunday with snow levels dropping from around 5500 feet to 4000-4500 feet. Even so, snow amounts, should they occur, look to be 1 inch or less. There is about a 20% chance of a few drips here in Medford during the wee hours of Sunday morning. But, we're really grasping at straws here. Impacts with this system will be minimal.

Monday should be mostly dry, then yet another weak disturbance arrives in the NNW flow aloft across the PacNW Monday night into Tuesday. This one could cause an uptick in afternoon N-NW breezes Tuesday, especially over the higher terrain and east side. Again, precip chances look low with slight chance to chance PoPs, highest over the mountains, but also in the north and over the east side.

A strong upper high will then set up near 40N and 140W around mid next week. This should provide dry weather Wednesday/Thursday as upper trough energy settles into California/Great Basin. The source of greatest uncertainty in the 12z models and ensembles for late next week into next weekend is the development (or not) of low pressure near the Great Basin/California and its progression (or not) next Friday to next Sunday. Some solutions (mostly ECMWF) favor consolidation of energy (upper low) near California Wednesday with retrogression offshore and even the potential of a rex block (high over low) off the West Coast by late next week. This would displace the northern branch jet farther north and keep our area more under the influence of the upper ridge (thus drier, milder conditions). Weaker and more progressive solutions (mostly GEFS, but also CMC) suggest potential for northern branch energy to remain nearby (cooler, wetter). The trend in the recent guidance has been for a drier solution during this time period and this follows the CPC 6-10 day forecast, which shows odds favoring below normal precip and above normal temps for SW Oregon and norCal Dec 4-8. Current forecast for next Friday brings an increase in PoPs, especially Cascades north and west, but this will likely change based on the scenarios mentioned above. Keep checking back for updates! -Spilde

AVIATION...28/18z TAFs

Overall, aside from local MVFR/IFR along the coast, this afternoon through early this evening should be VFR.

But, areas of valley LIFR/IFR are expected to follow later this evening into Saturday morning in the Umpqua/Rogue/Illinois and lower Klamath basins. These should clear to VFR again Saturday afternoon. -Spilde

MARINE...Updated 130 PM PST Friday, November 28, 2025

Conditions will gradually improve today as winds and seas ease, but steep seas will continue through this afternoon. Conditions continue to improve tonight through Saturday, but northerly winds then increase and remain gusty early next week. Conditions hazardous to small craft could return south of Cape Blanco late Sunday into Monday. Meanwhile, a long period swell (peaking around 7 to 10 ft at 16 to 19 seconds) builds in the waters Monday into Tuesday, which could maintain advisory level conditions early next week into Wednesday.

BEACH HAZARDS/HIGH SURF

Updated 200 PM PST Friday, November 28, 2025...There could be a brief period of a low sneaker threat Saturday afternoon as a 3-5 ft swell @ 15-16 seconds builds to a peak (6-9 ft @ 14 seconds) by Saturday evening. The higher risk for sneak waves, however, is expected on Monday. A distant storm will create a long period swell, and buoy guidance maintains the potential for this swell to bring a high sneaker wave threat beginning Monday morning and possibly continuing into Tuesday.

Guidance shows a long period swell arriving Monday, first arriving at around 3 to 5 ft at 21 to 22 seconds early Monday morning, which coincides with the incoming high tide that is anticipated by 8 am PST Monday morning. While sneaker waves can occur at any time, the greatest risk is on an incoming tide. We've issued a Beach Hazards Statement to highlight this risk for Monday morning through Tuesday afternoon, though timing may need to be adjusted by a few hours as we get closer to the event.

This swell is expected to peak at around 7 to 10 ft at 16 to 18 seconds Monday night, so we currently don't anticipate any high surf conditions at this time. If you have plans to visit the coast next week, particularly on Monday, please be aware of this potential and consider rescheduling your ventures to the beaches for another day. Sneaker waves run up significantly farther on beaches than normal. These waves can wash over rocks and jetties and can suddenly knock people off of their feet and sweep them into the ocean. They can also move logs or other objects which could crush or trap anyone caught underneath. Remember, NEVER turn your back on the ocean! /BR-y

MFR WATCHES/WARNINGS/ADVISORIES

OR...Beach Hazards Statement from Monday morning through Tuesday afternoon for ORZ021-022.

CA...None.

PACIFIC COASTAL WATERS...Small Craft Advisory until 4 PM PST this afternoon for PZZ350-356-370-376.