Good correlations can usually be drawn between weather factors + time of season and nectar flows, but I'm sure you can see there a good many variables there too. It's so easy for us to have weather this year where the bees either can't be out to forage enough, or there isn't a good flow on. It's really tough to gauge without picking frames out and examining, but yeah, activity is still a good thing to watch. Wet nectar in the hive will really tell you the story though.
BTW, throw away any assumption that we are experts here either :) as we all have different local variables, different climate conditions, different strains of bees, different levels of experience, different management styles, and are operating on a different day of the week. It's fun to watch here just what people are seeing in their areas and compare them with our own. I count my blessings that I don't have to deal with some of the issues that other folks do, but then I find myself envious of the guy in California with 11 supers stacked up who has a year-round flow. It's just different everywhere you go, and different for everyone. My mentor down the road had 100% loss this past winter. I had 10% loss. Yes we have different management techniques, but strangely enough, being 3 miles apart, our honey always tastes and looks vastly different. So many factors. I know that my bees have access to stuff up on teh side of the mountain that his don't, and at times it's the stuff up there that's providing the nectar flow, not the stuff down by us. But yes, this year is just topsey-turvey.
David, have a great vacation and watch to see what sources you see and what bee activity you spot while you're on vacation. It'll be interesting for you to comare it to your home environment upon your return. We also look forward to hearing how that super gets filled out.
Take care and be safe,
-Doug