I've been pondering what to wear at an upcoming conference in late spring, which will be in a much hotter climate than I'm used to. My vague idea is "casual professional", in that I want to look reasonably snappy without wearing a suit, which I suspect would be overkill for my profession as well as way too hot. I should note that at previous conferences of this sort, people tend to break out their "good" jeans and hiking boots and brush the dust off their sun hats. The only people who wear full-on business suits are typically graduate students giving their first public presentation.

With this in mind, I've been thinking about looking for a short-sleeved blazer-type jacket in a neutral color (black? beige? white?) that I can wear with jeans or trousers and a blouse or over a dress. Something like this, perhaps. Is this kind of jacket hopelessly frumpy?

ETA: I added some more ideas below!