Manza Onsen is wearing its koyo colours right now. The first dustings may arrive, but the base-building storms are still pending. A cold snap could whiten the tops, but it will not change the travel plan yet. Keep an eye on upper-elevation temperatures for the first proper base-building hints.
That makes Manza Onsen the 13th snowiest of 16 Gunma resorts we have reviewed.
Start with the upper-mountain wind and cloud line. The headline number only helps once you know whether a cold front pushing across the divide is the pattern to watch. With a 1600 to 2000 metre elevation band and 400 metres of vertical, the groomers tell the story quickly once the first few laps are done. A seasonal baseline around 7 metres means small clean refills matter more than waiting for a giant number. The swing variable is whether the upper lift can run with enough visibility to make the top worth using. If you are looking beyond the ropes, only chase that angle when the forecast also shows settled wind and stable visibility. Chase it after a cold storm only if the wind eases; if the top is socked in, wait for the next clear window.
See which resorts in Gunma are getting the best 24 hour totals and the next two days of snow.