A weak ridge is building into the region, bringing drying conditions and an end to recent showers. However, ski areas across the region remain closed as snow levels stay well above base elevations.
Tonight Through Wednesday: Fog Returns to Valleys
Showers across the area will taper off this evening as high pressure builds back into the region. Two cutoff low pressure systems will skirt the area through Tuesday, with one moving south and another heading north. This positions the region in a relatively dry zone between the two systems.
Warm and moist southwest flow will continue bringing intermittent cloud cover Tuesday, but clearing overnight will allow widespread fog formation in area valleys Tuesday and Wednesday mornings. I have medium confidence that dense fog will form, reducing visibility below one-quarter mile in lower elevation valleys Tuesday.
A weak cold front will move into the region Wednesday, bringing a 20% to 40% chance of mountain snow above 5,000 to 6,000 feet with valley rain possible in Baker County and the West Central Mountains. Temperatures will continue cooling throughout the period but remain 5 to 10 degrees above normal, with daytime highs in the Boise area reaching the mid to upper 50s through Wednesday.
Extended Outlook: High Pressure Dominates Weekend
The weather pattern will remain similar to recent days through early next week. An upper-level trough will split as it approaches the coast Thursday, with the southern portion developing into a cutoff low and moving south into California. This will result in only a 20% to 40% chance of showers across the area.
High pressure will build overhead through the weekend, potentially creating a temperature inversion under stable conditions. Low clouds and fog may become persistent in lower elevations if enough moisture gets trapped under the inversion. Temperatures are expected to average slightly above normal, though persistent low clouds and fog could reduce high temperatures.
Moisture is expected to move over the ridge late in the weekend into early next week. Weather models favor the ridge being strong enough to keep most moisture to the north through Sunday, resulting in lower precipitation chances than previous forecasts.
Monday brings a 30% to 60% chance of precipitation as an upper-level trough approaches the coast, with the highest chances in the northern mountains. Snow levels around 4,500 to 6,000 feet will keep precipitation as rain in lower elevations, with snow accumulations limited to the mountains.
Ski Area Status: Waiting for Winter Weather
Local ski areas remain closed as warm temperatures and high snow levels continue to delay the start of the winter season. With snow levels staying between 4,500 and 6,000 feet through next week, base elevations at most ski resorts will continue receiving rain rather than snow.
The persistent above-normal temperatures, running 5 to 10 degrees warmer than typical for mid-November, are preventing natural snowpack development at ski area elevations. Even when precipitation does occur, the warm air masses keep snow levels at or above where many ski areas are located.
Ski resort operators are monitoring weather patterns closely, but current forecasts suggest opening dates could even be pushed further into late November or early December. The lack of cold air masses from the north continues to be the primary factor preventing the temperature drops needed for snow production at lower mountain elevations.
Daily Forecast
Tonight: Patchy fog after 2 a.m. Otherwise, mostly cloudy, with a low around 41 degrees. Calm wind.
Tuesday: Patchy fog before 8 a.m. Otherwise, mostly sunny, with a high near 57 degrees. Light and variable wind.
Wednesday: Areas of fog before 8 a.m. Otherwise, mostly sunny, with a high near 54 degrees. Calm wind.
Thursday: A 20% chance of rain before 11 a.m. Mostly sunny, with a high near 55 degrees.
Friday: Patchy fog before 8 a.m. Otherwise, sunny, with a high near 54 degrees.
Friday Night: Mostly clear, with a low around 33 degrees.
Saturday: Mostly sunny, with a high near 53 degrees.
Saturday Night: Partly cloudy, with a low around 36 degrees.
Sunday: Partly sunny, with a high near 53 degrees.
Monday: A 30% chance of rain. Partly sunny, with a high near 54 degrees.
Stay connected right here for updates to forecast as we continued to await mountain snow!
