Figured I'd offer my 2 cents and some change opinion here about school closures after reading about that, in my cases.
They've become much more trigger happy than I remember from before I graduated HS. There are good reasons though most likely that I don't remember other cases (the case of tropical storms hitting us with significant weather didn't happen too much). School got cancelled and I'm pretty sure the city shut down for both Irma and Michael for at least one day, and then last year I had a snow day from school for moderate snow that didn't stick. I'm pretty sure the local schools that are below college just had a delay though and went on as scheduled. I think school also got cancelled for Matthew in the area, but I'm less certain there.
Outside Irma those cancellations were just for one day though I believe. The local schools turned into shelters for the coast for Irma. That was a very good deed by the city.
It's probably not a bad idea to cancel schools for tropical storm weather, just in my case they didn't cancel for severe weather before I graduated HS and I'm doubtful I had any Irma's or Michael's back then.