textproduct: Medford

DISCUSSION

High pressure and dry northwest flow aloft will keep dry weather going through the remainder of this week along with a warming trend. High temperatures today will be a few to several degrees above normal, but warmer air aloft will bring temperatures around 10-15F above normal from Thursday through the weekend. The air mass is pretty dry, but we'll get marine pushes from time to time that will bring bouts of nighttime/morning stratus to the coast, coastal valleys and Umpqua Basin. One such marine push is occuring this morning, which could be deep enough to cause some spillover clouds to bank up against the Siskiyous around the Rogue Valley this morning, but that's about it. By late Friday, models are showing a weak impulse offshore and some moisture/weak instability near the NorCal mountains (mainly south of here -- Sierra). This raises the idea of thunder, but the probability of anything occurring this far north is 10% or less. Same goes for Saturday pm/eve.

As we maintain the dry airmass and breezy afternoons, there will be at least an elevated threat for fire weather conditions each day. However, fuel conditions per fire agencies reveal the overall fire weather threat will remain low to moderate. Given the low RH values and breezy winds each afternoon, people should exercise caution with any outdoor activities that could cause sparks or flames. Bottom line is that fire season was declared early this year, so these precautionary actions should already be in place, but its especially important when we have these elevated fire weather days.

Looking ahead, there are indications that the ridge will begin to break down over the weekend, with the potential for a more robust trough to enter the Pacific Northwest around Memorial Day that could bring precipitation and cooler temperatures to the forecast area. Model suites still are not in solid agreement with this scenario, with several differences primarily in trough strength, but also its timing, so confidence is also still on the low side. This will warrant a close eye for those with plans for the Memorial Day holiday. Most inland areas should have a 5-10F cool down along with enhanced to locally gusty winds, and a chance of showers.

AVIATION...20/12Z TAFs

A weak impulse is passing over the region this morning, with a marine push resulting in IFR/MVFR ceilings over the marine waters and along the coast, and eventually the coastal valleys and Umpqua Basin by daybreak, including at North Bend and Roseburg. Marine layer depth (up to around 5000 feet) allows for the potential for some clouds to form and bank up against the Siskiyous this morning. These may cause local terrain obscuration but should be VFR above Medford. Any low flight conditions will clear through the morning or even early afternoon, with VFR then expected for the remainder of the TAF period. Elsewhere, VFR conditions will prevail through tonight.

MARINE...Updated 1200 AM PDT Wednesday, May 20, 2026

A thermal trough will bring gusty north winds and steep to very steep seas over the coastal waters through Friday night. Winds will be strongest and seas will be highest during the afternoons/evenings. Through this stretch, very steep seas of 10-12 ft are most likely south of Cape Blanco with steep seas (6-9 ft) north of Cape Blanco. Guidance shows winds will strengthen Wednesday/Thursday with the potential (35-55% chance) for gales (gusts) across portions of the southern waters, especially from around Gold Beach south.

The pattern will ease some this weekend as an upper trough pushes in from the NW. This should bring lighter winds and lower seas, especially by Sunday. Model scenarios indicate another trough moving through Sunday night into Monday, but the strength of the trough is the main source of uncertainty at this time. We should get a better handle on this in the coming days.

MFR WATCHES/WARNINGS/ADVISORIES

OR...CA...None.

PACIFIC COASTAL WATERS...Hazardous Seas Warning until 11 PM PDT Friday for PZZ356-376.

Small Craft Advisory until 11 PM PDT Friday for PZZ350-370.