textproduct: Pocatello

KEY MESSAGES

- Light snow in the central Idaho mountains north of Mackay and Galena Summit

- Much heavier rain and snow begins Tuesday night and continues through Thursday night. Snow returning to Snake River plain and eastern Magic Valley on Thursday morning.

- Windy to very windy Tuesday night through Thursday afternoon.

DISCUSSION

Issued at 1247 PM MDT Mon Apr 13 2026

Tonight through Thu afternoon...A weak upper level trough is triggering some light showers and the persistent northwesterly flow is finally bringing colder temperatures back to eastern Idaho. Light snow ends prior to midnight except for the northern half of the ID-WY border, where it continues light snow through Tue afternoon. Then after midnight Tue night, a more vigorous and moisture- laden snow storm arrives and continues over the area into the extended period. Very high likelihood of precipitation, the main forecast problem will be the snow levels and how much of the area will have heavy snow. Right now, most of the Winter Weather Advisories will be in the highlands and mountains, but it would not take much colder air to produce Winter Storm Warnings.

This first weak storm has enough cold air behind it to send Snake River plain and eastern Magic Valley temperatures below freezing, as in 20 to 30 degrees tonight. The second storm arrives very quickly on the heels of this storm, and temperatures have no chance to recover. Overnight lows will be slightly warmer, but still widespread 24 to 34. This is due to the second storm's cloud shield. Wed night is also sub-freezing for most, with temperatures down 1 to 3 deg F from the night before. High temperatures will still allow snow melt on Tue and Wed, but mountain locations on Thu afternoon will struggle to get above freezing.

This cold front on Wed also packs some wind, currently expecting the wind to reach Advisory level for at least the Arco Desert- Mud Lake region, perhaps more locations. Wind is even stronger on Thu. So, overall, this may be one of the stronger winter storms we have had all season.

Thu night through next Mon. By Thu night the snow is limited to the eastern half of the forecast area. Fri continues to see some light snow in higher elevations in the east and southeast highlands. It appears the storm clears out for the weekend, with Sun morning the next low starts affecting Custer County and the western edge.

Temperatures behind this front are bitter for this time of year. Single digit lows in the central Idaho mountains, and lows in the Snake River plain/eastern Magic Valley in the lower to middle 20s. Not time to plant your garden yet. The temperatures bottom on Thu night and Fri night, then rebound to staying in the lower to middle 30s by Sat night due to cloud cover from the next incoming low. The warming trend continues through the weekend and Mon is where temperatures level off. This is due to the next low moving through the northern half of the forecast area and dropping rain and high elevation snow.

Wind takes a while to turn calmer. Fri continues breezy to windy, then Sat is when it is more light to breezy. Afternoons continue breezy to borderline windy (20-25 mph) through the weekend and into Monday.

AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/

Issued at 932 PM MDT Mon Apr 13 2026

Models show low level moisture becoming widespread across the Snake River Plain overnight. Probably too much wind for fog, but MVFR/IFR stratus almost certain. This stratus will probably mix out late morning with gusty conditions developing for afternoon. SUN will probably turn upvalley around midday for a couple hours before switching to a crosswind around mid afternoon.

PIH WATCHES/WARNINGS/ADVISORIES

None.