Good morning, everyone!
Enjoy the warm and dry weather while it lasts, because big changes are on the way by Tuesday night. Through Tuesday, it will stay dry, breezy at times, and much warmer than normal.
Afternoon temperatures will run about 10 to 15 degrees above average, with lower 80s possible in the southern valleys and 60s to 70s in the mountains. It’ll be a nice stretch to get outside.
By late Tuesday, the pattern begins to shift as a Pacific storm system moves inland. Clouds will increase first, then showers begin to develop later in the day. There is also a slight chance for thunderstorms on Tuesday afternoon in eastern Oregon, with that thunder threat moving into western Idaho on Tuesday evening and central Idaho by Wednesday.
The wettest and most active part of this system looks to arrive Tuesday night into Wednesday. Expect scattered showers, a few thunderstorms, gusty winds, and a sharp drop in temperatures as a cold front pushes through. Some areas could see temperatures fall 20 to 30 degrees behind the front, making for a much cooler end to the week.
For the mountains, snow levels will drop to around 5,500 feet by Wednesday, which means several inches of snow will be possible in the higher elevations. If you have travel plans through mountain passes, be prepared for winter-like conditions to return.
Behind the front, strong west winds will develop Wednesday, especially across southeast Oregon and the Snake River Plain near the Nevada border, where winds may get close to advisory levels.
The unsettled pattern sticks around into Thursday with breezy conditions and scattered showers. Cooler-than-normal temperatures will continue, and snow levels will remain fairly low for late April, generally between 4,500 and 6,000 feet. Right now, models are picking up about 4 inches of snow by Thursday morning, but that number could go up as we get closer to Wednesday.
By Friday and into the weekend, moisture begins to decrease, so shower chances will become more limited and mainly focused over the higher terrain.
Looking ahead to Monday, conditions should finally begin to improve with drier weather and a slight warm-up returning to the region.
Impacts: Enjoy the warm weather early this week, but be ready for a big cooldown, windy conditions, thunderstorms, and mountain snow by midweek.
