When it starts
Grand Targhee, Dec 17–18, 2025: the model's run on the day said 4.0" skiable over 2 days, best Wednesday at 3.8" (Nice day); the Grand Targhee SNOTEL pillow gained 13" of depth. Model shy.
Model shy by 9.0". The usual direction: the 2025–26 backtest ran low on storm days.
Pack going in: 42" on Dec 16, 43" on Dec 17. The storm total counts from the first reading, so snow after 5pm the night before is in it.
| Day | Call | First chair | On hill | Skiable | Starts | Pillow before | Pillow after | Gain |
|---|---|---|---|---|---|---|---|---|
| Wed Dec 17 | Nice day | 0.5" | 3.3" | 3.8" | ~7am | 43" | 49" | +6" |
| Thu Dec 18 | Stay home | 0.0" | 0.2" | 0.2" | — | 49" | 55" | +6" |
Model: the run on the day (Open-Meteo Previous Runs, best_match). PowHound does not keep superseded live forecasts, so this is not the number you saw the night before. It is usually closer.
Clocks, local time: first chair 5pm–8am, on hill 8am–5pm, skiable is both. Stay home under 2", Nice day 2–8", Full Send 8" or more.
Pillow: snow depth at the Grand Targhee SNOTEL station, read once a day around midnight. A day's gain is the next midnight reading minus that day's, so it runs midnight to midnight, not 5pm to 5pm. Depth is not snowfall: new snow settles and blows around, so the pillow usually reads under what fell. Not the resort report.
Verdict: close is within 3" or 30%. Season numbers and method: llms.txt.