100 days of summer begins, by my reckoning, tomorrow – “Summer” in the U.S. is considered by most^{[citation needed]} to be the roughly 100 days from Memorial Day to Labor Day, which are the last Monday in May and First Monday in September respectively. Typically 14 full weeks plus a Monday—99 days—which every last one of us^{[citation needed]} will pad out to 101 by including the Friday & Saturday of the upcoming 3 day holiday weekend, which is how most of us (who don’t work retail or hospitality) celebrate these things.

So actually 101 Days of Summer – 101 and a half if you take off early on Friday like a lot of us might have already done.

In 2020 it’ll actually be 108 days of summer, because of the calendar, which just so happens to line up & give us 15 weeks of summer whenever Memorial Day lands on the 25th – this happens on average one-year-in-seven but not every seventh year, because of leap days; the interval is every 5-6 years (usually 6) except when it sometimes takes 11 years off. Enjoy the summers of 2020 & 2026 I guess is what I’m saying.

For a little more on that check out https://www.popsci.com/article/technology/next-summer-already-better-summer

“100 days of summer” is an expression^{[?] [citation needed]} common enough that I seem to remember hearing it well before 500 Days of Summer riffed off the common[?] idiom for its title in 2009. But maybe it isn’t as common as I think, or maybe my brain misfired after the movie came out and it’s just a back-formation that makes its own kind of sense because what we call “Summer” in the vacation-planning but not astronomical or meterological sense just happens to be 100 [ok: 101] days.

I was also planning a “100 Days of Summer” diary/planner – sort of a smaller, pocketable extension of my Weekend Planner idea – but didn’t manage to make anything I liked, let alone would consider selling, in time for Summer 2019. Which starts tomorrow.

I guess I’ll file that idea away for now, maybe to be picked up again when I have time off in the Fall, though I suppose for 2020 I should just go ahead and title it “108 Days of Summer” to be accurate.

Outside of things like students’ assigned summer reading, for most of us Summer isn’t considered a time for big undertakings, but 100 is a big round number and Summer is the sunny, beautiful time of year most of us (at my latitude) spend completely indoors, all the time, with the air conditioning on – so maybe 101 Days of Summer would be a good time to line up a lot of little daily things that would add up into a new skill or a sizable chunk of some kind of project.