Definition of corn snow in US English:

corn snow

noun

North American
  • Snow with a rough granular surface resulting from alternate thawing and freezing.

    • ‘Sailing is especially fun in the spring, when the wind is warmer and there's good corn snow.’
    • ‘The perfect corn snow was ripening in the sun, and a velvet 45 degree pitch dropped below us like a frozen plume of whitewater.’
    • ‘Below us is 4,000 vertical feet of superb, low angled corn snow - a velvet road leading straight to the lodge.’
    • ‘It's suddenly obvious how a backcountry challenge, even more than perfect corn snow or nights in the Post Hotel, can make our relationship complete.’
    • ‘The flavor of skiing on a perfect day is spiced by the knowledge and experience of conditions far less ideal, from the early season rock ski to the last patches of corn snow.’

Origin

From corn in the dialect sense ‘granule’.