FXUS65 KPIH 181816 AFDPIH Area Forecast Discussion National Weather Service Pocatello ID 1216 PM MDT Mon May 18 2026 .KEY MESSAGES... - Gusty northerly winds diminishing later on today - Best chance of precipitation today across the southeast corner - Frost/freeze conditions through at least midweek before temperatures begin warming up && .DISCUSSION... Issued at 1209 AM MDT Monday May 18 2026 Strong low pressure will continue slowly churn to our south and east today. This will keep a persistent area of light rain and snow, with a few thunderstorms possible across the southeast corner. We could see snow falling at lowest elevations but anything that falls and accumulates should melt later in the day. Across the the higher elevations, a couple of inches are possible. We should also see a few showers across the central mountains south across the Magic Valley and Albion Mountains during the afternoon and evening hours. The bigger overall issue is strong northerly winds, which should be peaking early this morning, but lingering through the day. We do expect some spots to exceed the low end for WIND ADVISORY, but those pocket should be small enough to keep us from issuing something. That said, we are going to easily exceed the northeast wind threshold for American Falls Reservoir, therefore we will keep the LAKE WIND ADVISORY in place for today. The other issue is colder temperatures. We do have a FREEZE WARNING and FROST ADVISORY out for the Snake Plain and Magic Valley this morning. At the moment, the wind is helping keep temperatures pretty warm. However, we are seeing colder air slipping across the Montana border. That, in conjunction with the usual drop in temperatures overnight, we see no need to end the headlines in place for this morning. For tonight, with less wind, we are likely in line for another round of Frost/Freeze headlines. We will also have less cloud cover around. Highs today barely top out above 60 in a few spots. We should see a few showers and potentially isolated storms closer to the Montana border Tuesday afternoon and evening. At the moment, this may be a simple round of virga/sprinkles, but certainly worth mentioning in the forecast. Another wave drops south and east for a better chance of precipitation and thunderstorms Wednesday night and Thursday. We may see a few showers and storms daily heading into the weekend especially closer to the Montana border. Temperatures do eventually starting warming up, heading actually toward AVERAGE through midweek and ABOVE AVERAGE later in the week, as we switch from north/northwest flow to southwest flow. && .AVIATION /18Z TAFS THROUGH 18Z TUESDAY/... Issued at 1210 PM MDT Mon May 18 2026 VFR conditions through the forecast period. Gusty N/NE winds remain in place for the Snake Plain/Teton Valley terminals and these will continue into the early evening before beginning to taper off, becoming more light and variable overnight and into the day Tuesday. KSUN and KBYI will see a more westerly wind component this afternoon and evening and not nearly as breezy as the other locations. Not expecting any precip at terminals through the period with skies becoming more clear into Tuesday. && .PIH WATCHES/WARNINGS/ADVISORIES... Frost Advisory from 3 AM to 9 AM MDT Tuesday for IDZ051-055. Freeze Warning from midnight tonight to 9 AM MDT Tuesday for IDZ052>054. && $$ DISCUSSION...Keyes AVIATION...McKaughan