Per recommendations in this post, I just ordered a Specialized "gilet" which is on sale right now in limited sizes. It is high-vis yellow with a vented back, which are two things I wanted. Unfortunately, I didn't order from the Specialized web site as it's sold out in the medium size, so I had to scour the Interwebs to find one in that size.

Specialized Men's HyprViz SL Pro Wind Gilet
https://www.specialized.com/us/en/me...ro-wind-gilet/