Weather
A mostly manageable weekend and Monday transition into the highest-confidence snow window from Tuesday through Thursday, followed by a larger but lower-confidence storm signal for Saturday into early next week. Guidance is most aligned on a moderate midweek refresh, strongest in central Honshu, where many mountains should pick up 10 cm-35 cm, with the wettest favored terrain closer to 25 cm-45 cm.
From Saturday night through Monday, the model suite is converging on only intermittent light snow and plenty of usable ski windows, with timing agreement better than intensity agreement. Most guidance keeps this first period weak, but there is divergence on exactly which mountains collect a few extra centimeters, especially in Hokkaido and northern Honshu. The more coherent storm arrives Tuesday, builds Tuesday night, and tapers Thursday, and confidence is higher on that timing than on peak intensity. Snow-level guidance is converging on mostly 300 meters to 1,100 meters while it is snowing, with brief warm pushes near 1,300 meters before levels fall again. Wind guidance for this period is also fairly aligned, generally 10 km/h to 30 km/h with periodic exposed-ridge bursts around 40 km/h to 60 km/h. SLRs are mostly 8-10 early in bursts (dense snow), then closer to 10-13 late Wednesday into Thursday (moderate to occasionally lighter quality), with ski-period temperatures generally near -6 C to 1 C during active snowfall.
Friday looks like a short reset window, then confidence drops as a broader weekend-to-early-week storm envelope develops with larger spread in intensity, snow levels, and wind impacts. The extended guidance still leans snowy overall, but it diverges on how quickly the core energy consolidates and where it focuses, with ECMWF, AIFS, and GFS generally supporting a stronger regional cycle, ICON lighter through Saturday evening, and GDPS remaining the wet outlier in parts of Honshu. A realistic conservative envelope from Saturday through Monday is around 15 cm-45 cm for many resorts, with favored western and northern terrain capable of 30 cm-70 cm if the wetter scenario verifies. Snow levels during the first phase of that storm are most often projected near 400 meters to 1,000 meters while it is snowing, then trending lower by Sunday. SLRs should run near 7-10 at onset (dense) and improve to roughly 10-14 later (moderate to lighter), while exposed terrain can see 30 km/h to 70 km/h winds with stronger gusts.
Resort Forecast Totals (Tue Mar 03 – Thu Mar 05)
- Hakuba Happo-one – 27 cm-43 cm
- Naeba – 20 cm-32 cm
- Appi Kogen – 15 cm-26 cm
- Kiroro – 15 cm-23 cm
- Madarao Kogen – 13 cm-22 cm
- Shiga Kogen Okushiga Kogen – 12 cm-20 cm
- Nozawa Onsen – 12 cm-20 cm
- Hoshino Resort Tomamu – 11 cm-17 cm
- Zao Onsen – 8 cm-14 cm
- Gala Yuzawa – 5 cm-9 cm
- Akakura Onsen – 4 cm-7 cm
- Niseko Grand Hirafu – 4 cm-6 cm
- Rusutsu – 3 cm-6 cm
- Sapporo Teine – 2 cm-3 cm
- Furano – 1 cm-2 cm
