When is it Termination Dust?

In the first week of June this year, the snow level dropped down to around 3000 feet one night. Until the heavy low overcast started breaking up in the evening, it was difficult to see the snow on the mountains, but it’s possible to see remnants of it on the upper slopes of Bear Mountain. June snow in the mountains is certainly not unprecedented, though it tends to be uncommon, and in this year of early melting, it stood out more than it might have otherwise. This year it occurred to me that I don’t really consider such snow termination dust (marking the end of summer) like I do when it occurs in September.

Questions about mountain snow:

  • What’s the earliest we should talk about snow as being termination dust marking the end of summer rather than a last gasp of winter?
  • What is the frequency of snow between 3000-4000ft (where it’s most noticeable on peaks near town) throughout the year?
  • Has anyone noticed such snow in July or August? (I don’t recall seeing it between mid-June and mid-September)
  • What about frost? It’s much less easy to tell, but how often does it drop below freezing at various elevations? (this might be a good ibutton project).

Leave a Reply