Fri Feb 21 03:32:35 PM EST 2025 Arco/Mud Lake Desert-Upper Snake River Plain- Including Mud Lake, INL, Craters of the Moon NM, Idaho Falls, Rexburg, and St. Anthony 131 PM MST Fri Feb 21 2025 .TONIGHT...Mostly cloudy. Patchy fog. Lows 11 to 18. East winds up to 10 mph. .SATURDAY...Mostly cloudy. Patchy fog in the morning. Highs 29 to 36. Light and variable winds...becoming southeast up to 10 mph in the afternoon. .SATURDAY NIGHT...Increasing clouds. Lows 13 to 23. Northeast winds up to 10 mph. .SUNDAY...Cloudy with a chance of snow and rain. Highs 33 to 40. South winds around 10 mph. Chance of precipitation 50 percent. .SUNDAY NIGHT...Mostly cloudy with a chance of rain and snow. Lows 26 to 36. Southwest winds 10 to 20 mph. Chance of precipitation 50 percent. .MONDAY...Partly sunny. Highs 39 to 46. .MONDAY NIGHT...Mostly cloudy with a chance of rain and snow. Lows 24 to 34. .TUESDAY...Partly sunny with a chance of snow and a slight chance of rain. Breezy. Highs 38 to 45. .TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...Mostly clear. Lows 13 to 23. Highs 34 to 41. .THURSDAY THROUGH FRIDAY...Partly cloudy. Highs 38 to 46. Lows 18 to 27.