textproduct: Medford

DISCUSSION (Today through Tuesday)

Key Points:

* Overall, minimal weather impacts through this weekend * Mostly light rainfall chances expected through tonight - No snow expected * Next widespread chance for precipitation is early next week - Could be as early as Sunday - Snow: Snow levels are high 6,000+ ft - Little to no snow accumulation expected - Rain: Mainly for Coastal areas, Cascades, & Umpqua Basin - Highest chances for accumulation of at least 0.25"/24hrs - Wind: Advisory level wind speeds possible early next week - Mainly eastside areas and Shasta Valley

Further Details:

Our weather across the PacNW continues to be dominated by an area of low pressure over parts of northern British Columbia and high pressure off the coast of California. This setup is allowing for a large swath of moisture advection into the region between these two features. By far and large, all the weather impacts continue to be north of our forecast area where considerable rainfall has resulted in significant river rises, especially across Washington. In other words, we are only expecting light rainfall through Thursday morning given the location and strength of the high pressure. Eventually, the ridge of high pressure does break down, and the orientation shifts to allow this moisture plume to go farther north into Canada Thursday through Sunday. Through this stretch, we are expecting dry conditions. There continues to be uncertainty on the next potential area of low pressure impacting the region, but it could be as early as Sunday. Deterministic and ensemble members have a strong signal for rainfall chances increasing by Monday and continuing through at least middle of next week. Snow levels are really high early next week, and at this time very little snowfall is anticipated. Cluster analysis continues to show a split (ridge vs trough) with 5000mb heights early next week. This doesn't lead to high confidence with some of the exact details. The probability for at least 0.50" of rainfall over 24hrs is about 40%-80% with higher chances along/near the coast and Umpqua Basin with decreasing chances elsewhere inland. Very low chances (0%-30%) for these probabilities on the eastside. The probability for at least 2.0" of snow over 24 hours is only around 25% Monday night through Tuesday night for the Cascades north of Highway 140. Furthermore, most ensemble members don't start accumulating snowfall until middle of next week. In other words, we still have some details to hash out, but early to middle of next week does look to be the next potential active weather pattern.

A note on Crater Lake snowfall: the latest Crater Lake has had zero snow depth was December 26th, 1976. Record keeping began in 1919 for Crater Lake, and we have only had 9 years where we went into December for the last snow depth of zero. This will be the 10th year, and will likely rank at least 3rd latest ever. In 1958, we went until December 20th, and in 2008 we went until December 11th.

-Guerrero

AVIATION (00Z TAFs)

A somewhat complicated TAF cycle is anticipated for at least a couple terminals, so confidence is low overnight for fog and low clouds. KMFR will likely remain in IFR conditions as satellite doesn't show much erosion of this cloud layer across the Rogue Valley. Conditions will likely remain at least IFR and likely transitioning LIFR overnight for both fog and low clouds. The other inland terminals will be tricky, but decided to keep both KRBG and KLMT in VFR through this cycle. This could end up needing an amendment, but soundings did show enough dry air for this choice of conditions. KOTH will likely see at least MVFR conditions overnight.

-Guerrero

MARINE...Updated 200 PM PST Wednesday, December 10, 2025

Seas remain hazardous to smaller crafts as high and steep swell persists this evening through tonight. Conditions improve Thursday evening into the early weekend as high pressure builds and seas lower.

The next big weather concern will be around Monday as a low deepens out in the Pacific and models are showing a cold front swing through the waters to our north. Right now, southerly gales are looking more probable than not around 60 to 70 percent.

MFR WATCHES/WARNINGS/ADVISORIES

OR...None.

CA...None.

PACIFIC COASTAL WATERS...Small Craft Advisory until 10 AM PST Thursday for PZZ350-370.