December and January are good bets.
I saw a couple fluttering around during the recent ceremony. Also saw one this week in my yard. They are moving around still. When they cluster it looks like dead leaves and I've seen them best with binoculars or scopes the volunteers set up. So yes here but no not clustering yet that I saw. But the last couple of cold nights has probably changed their behavior. I'm not a pro just a monarch lover.
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