FXUS65 KPIH 120511 AFDPIH Area Forecast Discussion National Weather Service Pocatello ID 1011 PM MST Thu Dec 11 2025 .KEY MESSAGES... - Warm weather continues into next week - Light rain or snow expected in the eastern highlands tomorrow - Wet and windy conditions likely starting later Monday && .SHORT TERM /THROUGH FRIDAY NIGHT/... Issued at 1200 PM MST Thu Dec 11 2025 The main story to round out this week is the well above average temperatures remaining place. We are looking at near record or likely record highs today in some spots as temperatures remain in the 50s to near 60 in lower valleys and 40s to near 50 for higher valleys. Temperatures fluctuate little tomorrow, so we will likely see that same potential exist. We are looking a surge of moisture clipping areas along the Montana border and Lemhi County tonight and Friday. We could see some very light precipitation in the Frank Church, but area real potential for measurable precipitation is around Island Park. Up to 0.10" is possible mainly across higher elevations there, with a 40-50% chance of more than that at highest elevations and a 20-30% chance of more than 0.30" in the mountains adjacent to Yellowstone. It will be a fine line due to strong northwest flow between hardly anything and those highest amounts. This is a small window for light snow or flurries to fall at the floor of the caldera, but real accumulation will be higher up. Impacts over Raynolds and Targhee Passes are not expected. The rest of central and eastern Idaho will be dry. We have seen some fog across the northern end of the Snake Plain, extending out through the INL and up toward Island Park. It has been stubborn to dissipate around Sage Junction and the Camas/Market Lake area. The models don't really have a good handle on that. We believe that eventually dissipates and we should have no fog issues tonight. We will need to monitor this closely and see if we have a repeat in the same area or other pockets of fog develop this evening. We did include freezing fog up north for tomorrow night and Saturday morning. There is a better hint at its development, plus we have a weak ridge shifting overhead during the weekend. && .LONG TERM /SATURDAY THROUGH THURSDAY/... Issued at 1200 PM MST Thu Dec 11 2025 High confidence in well above normal temperatures across eastern Idaho this weekend and into the first part of next week with high pressure in control of the weather. Valley highs in the upper 40s to mid 50s are expected with mostly clear skies throughout the weekend. This remains around 20 degrees above normal for mid-December. Even our overnight low temps are within a few degrees of where the daytime highs should be so saying things are mild could be an understatement. The ridge looks to break as we get later into the day on Monday and this is when it looks like the upper flow becomes more zonal allowing for Pacific moisture to return to the region for the middle part of next week. This is when the forecast becomes tricky as cluster analysis shows wildly differing views on the potential upper level pattern. For now, it seems like a shortwave will move north of the area through the brisk upper flow aloft which should produce some precip potential Tuesday into Wednesday. Snow levels will be high initially but lower throughout the day Wednesday but it still looks like any accumulations will be limited to the higher terrain of the eastern highlands and central mountains. The tight pressure gradient should keep conditions breezy across the Snake Plain and Magic Valley Tuesday-Thursday next week. Still some uncertainty though during this period so stay tuned.&& .AVIATION /18Z TAFS THROUGH 18Z FRIDAY/... Issued at 1101 AM MST Thu Dec 11 2025 VFR conditions expected to prevail through the period with justsome mid/high level clouds streaking across the region into the day Friday. Winds will remain quite breezy at KPIH and KIDA up to around 30 kts or so through the afternoon before they lessen during the overnight hours. KSUN, KBYI and KDIJ will see winds more around the 10-15 kt range with an occasional gust upwards of 20 possible. No precip is expected. && .AVIATION /06Z TAFS THROUGH 06Z SATURDAY/... Issued at 911 PM MST Thu Dec 11 2025 High pressure dominating the pattern keeps CIG and VSBY issues away for KSUN, KBYI, KPIH, and KIDA. KIDA and KDIJ are the only ones expected to observe a CIG, with KDIJ as low as 6000ft AGL with SHRA in the vicinity during the late morning to early evening. && .PIH WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Keyes LONG TERM...McKaughan AVIATION...Messick