Overall, it has been a calmer start to our Thursday compared to the treacherous weather conditions on Wednesday. Boise received a record-breaking 5.2 inches of snowfall, the most for any January 10th on record. Meanwhile, Canyon county picked up 1-4 inches, most of which fell in a short, 3-hour timeframe.
Wednesday saw some melting as temperatures climbed into the mid-30s along with a few peaks of sunshine. However, the melted snow refroze overnight, creating slick spots. Temperatures will remain chilly, with highs in the low to mid-30s.
In the central mountains, an inch or two of snow fell overnight, but heavier snowfall moved through the afternoon as an arctic front traveled through Idaho. In the Treasure Valley, on-and-off snow showers will transition into a steadier snow overnight.
As the front approaches, wind will increase, and snowfall rates will get heavier. This will lead to hazardous driving conditions for the Friday morning commute. Use extreme caution if you have to travel!
Temperatures will hold steady in the lower 30s until Friday morning, but once the front passes through, they will drop into the 20s and eventually the 10s for the rest of the day. The Treasure Valley will see 2-4 inches of snow accumulation, with higher amounts anticipated in the Boise foothills.
A Winter Storm Warning will be in effect from 11:00 PM tonight (Thursday) until 11:00 PM Saturday for the Treasure Valley, eastern Oregon and the central mountains. A Blizzard Warning will be active from 5:00 PM Thursday evening for the Owyhees, the Magic Valley, and eastern Idaho. Snow will start in southern Idaho later in the evening, with strong winds and heavy snow developing overnight. Wind gusts of 50-60mph will cause whiteout conditions at times.
The arctic front will stall near the Nevada border, limiting snowfall to areas south of the Treasure and Magic valleys, resulting in a brief break Friday afternoon through Saturday morning. However, a warmer Pacific system will bring heavy snowfall to the valley as significant moisture overrides the cold arctic air.
Weather models diverge regarding the snowfall on Saturday, with some projecting upwards of a foot of snow in Boise and others predicting most of the heavy snowfall to remain off to the south. In any case, difficult travel conditions are expected due to gusty winds over 45mph, reduced visibility, and blowing snow on roadways. Mountain travel will be almost impossible.
Heavy snowfall will persist in the mountains until Sunday morning, with 8-12 inches in the mountain valleys and 12-24+ inches at higher elevations and for ski resorts. The snow will taper off on Sunday, but frigid arctic air will remain in place until early next week. Highs will be in the 10s and 20s, with overnight lows potentially reaching single digits or below zero. Dry conditions persist until Wednesday when another round of snow is anticipated.
