Last one came out today outside, a female. We had about 20 inside this summer, and the last ones left late last week. Just in time--37 and frost tonight.
We didn't see monarchs until mid July, and then not that many. A few days 3-5 would come in, but usually just 1-2 each day. And not many eggs or cats. Last year I had 30+ larvae on one milkweed at one time, this year the record was 6. Of course, several succumbed to tachnid flies or ambush bugs.
Certainly concerned about the off summer here, a dry Texas, and a smaller refuge in Mexico. I keep planting more milkweed, and religiously toss seed out my car window on my semi rural roads as I drive to work. (Not many in my new neighborhood plant trees, let alone shrubs or flowers--sod right up to the house walls!)