Area Forecast Discussion
Issued by NWS Pocatello, ID
Issued by NWS Pocatello, ID
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262 FXUS65 KPIH 280546 AFDPIH Area Forecast Discussion National Weather Service Pocatello ID 1046 PM MST Thu Nov 27 2025 .KEY MESSAGES... - Occasional mainly mountain rain and snow showers continue. - Above average temperatures through Friday. - Cold unsettled conditions continue throughout the extended, with potential for light snow accumulations down to valley floors at times. && .SHORT TERM /THROUGH FRIDAY NIGHT/... Issued at 128 PM MST Thu Nov 27 2025 Quiet weather and mostly mild temperatures in place across much of eastern Idaho on this Thanksgiving afternoon. Afternoon satellite imagery shows cloud cover gradually on the increase however, especially in SW Idaho, and this cloud cover will make its way back into our area overnight and into Friday morning. Until then however, temps are quite mild for late November with upper 40s to mid 50s in place across the lower valleys this afternoon. Today will be the warmest day though over the next week as things take a downward trend beginning tomorrow. Dry conditions will continue across the area until tomorrow. That`s when an upper level shortwave will swing through the region bringing with it increased cloud cover and precipitation chances once again. Looks like precip will mostly be limited to the higher terrain of the central mountains, along the Montana Divide and into the eastern highlands. Cooler temps tomorrow will support snow as the dominant precip type in these areas but this system won`t have much moisture with it so with QPF generally around a tenth or less, snowfall amounts are likely to be an inch or less for most areas that do see precip. Some higher mountains passes and peaks could get a touch more. Not expecting much, if any, precip to fall in the lower valleys tomorrow although a stray shower or two is certainly possible. Temps in the Snake Plain would likely support more of a rain/snow mix, especially if during the afternoon hours. Either way though, not expecting anything overly impactful if/when precip does occur in our valley areas. Temps Friday will be about 5-10 cooler than today with them continuing to trend down as we move into the weekend. More on that below. && .LONG TERM /SATURDAY THROUGH THURSDAY/... Issued at 128 PM MST Thu Nov 27 2025 Series of shortwaves expected to impact East Idaho through the extended, increasing deep and cool northerly flow and introducing the potential for light snow even to lower elevations. The first shortwave arrives Sat into Sunday, but a lack of significant moisture will keep precipitation amounts light with minimal, if any, travel impacts. The highest snowfall amounts look to be Sunday into Sunday night with generally 1-3" across higher elevations in the southern and southeast highlands. Cooler air mass is in place for Sunday into Monday, with daytime highs in the 30s and overnight lows in the teens. Once again the deterministic NBM temps are outliers to the spreads, so could see some changes in forecast temperatures moving into the weekend. Following a break in the precipitation Monday, next shortwave drops into the region Tuesday. Differences in the ensemble clusters are starting to become more amplified this far out, leading to differences in precipitation potential for East Idaho. Temperatures still look cold enough to sustain snow or brief mix in the afternoon with potential for light accumulations even to valley floors. Looking ahead to the latter half of the week, ensembles diverge significantly, with a roughly 60/40 split between rebuilding a ridge across the west or introducing a faster system to the PacNW. There is little certainty by the time we reach the end of the forecast period. && .AVIATION /06Z TAFS THROUGH 06Z SATURDAY/... Issued at 1047 PM MST Thu Nov 27 2025 Generally low-impact VFR conditions will continue through late Friday morning. Starting midday, winds will increase out of the WSW, especially at KBYI and KPIH, along with some increased cloud cover as our next shortwave trough crosses the region. A shift from SE to WSW winds is still expected during the afternoon at KSUN (supported especially in MOS guidance) as advertised in the TAF. CAMs remain fairly "light, spotty, and messy" with regard to supporting rain/snow shower activity with this shortwave (with a few of our mountain ranges favored with the best chances), but we have started to incorporate some trends into the new 06z TAFs just issued. KIDA has been upgraded to VCSH starting at 23z/4pm Friday as passage of a cold front with this system looks a bit wetter on the latest model runs, although we keep conditions VFR for now. At KDIJ, we have nudged previously-added VCSH to start later at 20z/1pm, but have also now added a period of impacts along the cold front with 3SM -SN and MVFR cigs starting at 23z/4pm, likely to last for several hours. There is some potential for cigs/vsbys to go lower as well...we`ll continue to adjust the forecast based on trends and model consensus as confidence increases and we get closer. Behind the front Friday evening, also wondering if north winds will take over at the surface at KIDA and how strong they might be with strong drainage out of the valleys of the eastern central Mountains to the north/west and hints in model VWPs of strong north winds aloft approaching LLWS criteria. Stay tuned as we watch this as well. && .PIH WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...McKaughan LONG TERM...DMH AVIATION...01