Area Forecast Discussion
Issued by NWS Pocatello, ID
Issued by NWS Pocatello, ID
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106 FXUS65 KPIH 232356 AFDPIH Area Forecast Discussion National Weather Service Pocatello ID 456 PM MST Sun Nov 23 2025 .KEY MESSAGES... - Wind Advisory Noon to 8 PM Monday for west winds 20 to 30 MPH gusting 50 MPH eastern Magic Valley and Snake Plain corridor; difficult driving conditions for high profile vehicles. - Quick round of mountain snow tonight through Monday thanks to the same cold front bringing Monday`s wind. - Unsettled pattern ahead and the potential for much colder temperatures late in the weekend into early next week. && .SHORT TERM /THROUGH MONDAY NIGHT/... Issued at 140 PM MST Sun Nov 23 2025 This morning`s patchy dense fog has finally eroded and many of us are enjoying some afternoon sunshine. As we soak it up, highs will return to the mid and upper 40s for most with a few low 50s here and there. Late tonight, a cold front begins to work its way into our CWA and it will bring some mountain snow and gusty winds with it along with cooler air, but the chill won`t reach most of us until Tuesday. Since this is a quick moving front on Monday, we`re not expecting too much precipitation with it. In fact, most of us in the eastern Magic Valley and Snake River Plain will stay totally dry with most of the snow confined to our mountains once again. There`s about a 10 percent chance for at least an inch of snow up near Stanley, about a 30 percent chance of the same for Victor and Island Park, and about a 40 percent chance of at least an inch for Pine Creek Pass and Emigration Summit. It will be above 8000 feet or so where we see the bulk of our snow and that will be closer to 2 to 7 inches for our mountains by the time snow ends late Monday night into early Tuesday morning. What more of us will notice on Monday will be the wind. As the cold front moves through, expect winds to increase quite a bit from the "light" winds we`ve been enjoying for most of this last week and weekend. Sustained winds will generally range from 20 to 30 mph with gusts up to 50 mph. Have gone ahead and issued a Wind Advisory for the eastern Magic Valley and Snake River Plain for Monday from noon to 8 PM. The NBM is showing about a 40 percent chance of 50 mph gusts and a 60 to 80 percent chance of gusts greater than 45 mph from Carey across the Arco desert/Craters of the Moon area to Atomic City. It`s about a 20 to 40 percent chance of 45 mph gusts from American Falls up to Idaho Falls and about a 15 percent chance of 50 mph gusts. As noted by the advisory ending at 8 PM, winds will diminish in the evening and will be much lighter on Tuesday. && .LONG TERM /TUESDAY THROUGH SUNDAY/... Issued at 140 PM MST Sun Nov 23 2025 Shallow upper ridge is in place for Tuesday through Thanksgiving Day, There is still some expectation for weak energy to overtop the ridge especially Wednesday and Thanksgiving for light precipitation mainly higher elevations. Travel impacts should be minimal, if any for these days. Ensembles diverge on details for the remainder of the forecast period, but the general tone remains similar to previous days. Incoming PacNW shortwave dives south through the western states Friday into Saturday, developing a deep trough across the Intermountain West for the weekend. Showers become more widespread Friday and Saturday, with potential for light snowfall to reach valley floors by late Saturday. What could be the coldest air mass of the season so far looks possible for Sunday into early next week. There is still a lot of spread in the ensembles, and significant differences in the depth of the trough via the ensemble clusters. Thus there is still a lot of potential for change this far out in the forecast. As of now, the probabilistic chance of forecast highs BELOW freezing for lower elevations Sunday and Monday are roughly 15-35% for most lower elevation areas. && .AVIATION /00Z TAFS THROUGH 00Z TUESDAY/... Issued at 456 PM MST Sun Nov 23 2025 An approaching shortwave trough will bring thickening mid-level clouds this evening and tonight, with high confidence in any cigs remaining solidly VFR through late morning Monday at KBYI/KIDA/KPIH, and through at least sunrise at KSUN/KDIJ. We then advertise a period of VCSH at all terminals...latest round of CAMs supports the best chance of rain/snow showers near KSUN and KDIJ, but confidence is too low to upgrade beyond VCSH at this time for precip. Cigs may be close to the MVFR threshold with these showers at KSUN/KDIJ. Elsewhere, expect winds to increase as VCSH potential decreases and ends, with a cold front crossing the region during the afternoon. Strongest winds start 16-18z/9-11am Monday depending on location. A Wind Advisory is in effect for the eastern Magic Valley/Snake Plain corridor including KBYI/KPIH/KIDA, translating into a solid 20g30kts locally at KPIH/KIDA and still breezy at all other terminals. Watching KSUN and KDIJ for the potential to get close to LLWS criteria for a time Monday afternoon...standing by for some more hourly VWP forecast data as we get closer to evaluate this further and watch trends. && .PIH WATCHES/WARNINGS/ADVISORIES... Wind Advisory from noon to 8 PM MST Monday for IDZ051>055. && $$ SHORT TERM...AMM LONG TERM...DMH AVIATION...01