Weather Alerts For Sisters, OR

URGENT - WINTER WEATHER MESSAGE National Weather Service Pendleton OR 141 PM PST Tue Dec 16 2025 East Slopes of the Oregon Cascades- Including the cities of Camp Sherman, Sunriver, Sisters, and La Pine 141 PM PST Tue Dec 16 2025 ...WINTER WEATHER ADVISORY IN EFFECT FROM 1 AM TO 4 PM PST WEDNESDAY ABOVE 4000 FEET... * WHAT...Snow expected above 4000 feet. Total snow accumulations of 3 to 7 inches. Winds gusting as high as 65 mph. * WHERE...East Slopes of the Oregon Cascades. * WHEN...From 1 AM to 4 PM PST Wednesday. * IMPACTS...Plan on winter weather driving conditions. Periods of moderate to heavy snowfall, very strong winds, and blowing snow could significantly reduce visibility along US 26 and US 20. * ADDITIONAL DETAILS...Near-blizzard conditions characterized by very strong winds and low visibility are expected with the passage of a strong cold front Tuesday night into early Wednesday morning. Temperatures will fall quickly with the passage of the cold front. PRECAUTIONARY/PREPAREDNESS ACTIONS... Slow down and use caution while traveling. The latest road conditions can be obtained by visiting tripcheck.com online, or by calling 5 1 1. &&

There is a Marginal Severe Storm Risk for your location. Continue reading for today's outlook from the National Weather Service's Storm Prediction Center. -------------------- National Severe Storm Outlook THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE PACIFIC NORTHWEST SUMMARY Sporadic severe gusts may accompany low-topped convection across parts of the Pacific Northwest tonight into early Wednesday morning. Pacific Northwest A vigorous shortwave trough will reach coastal WA by late tonight and spread inland through 12Z Wednesday. This trough will be accompanied by an intense tropospheric wind field, characterized by 70-90 kts at 700 mb, that will spread across WA and OR during 06-12Z. A surface cyclone will move onshore in BC and occlude, as downstream lee cyclogenesis occurs over southern AB. Low-topped convection is expected to increase along the trailing cold front attendant to the occluded cyclone, initially reaching coastal WA towards 06Z. Surface-based buoyancy will be scant along the front, but sporadic lightning flashes and occasional strong to severe-caliber wind gusts may accompany the passage of this low-topped convective line. Low-topped convection should also increase ahead of this line overnight, as strong large-scale ascent coincides with peak low to mid-level flow. With minimal instability, low confidence exists in the degree of convective enhancement beyond the gradient winds. Thus, the level 1-MRGL risk has been maintained with no changes.