Waistcoat only?

[Tenmiles]

Oh to be sure, and we grin and bear it; but that's not to say the frequency of 'aside' comments we make to each other in our commiseration is any less. Oh how we delight in overcast or rainy days, that the weather has decided to reenact along with us.

[MacCathmhaoil]

One adapts to the weather conditions as one needs, even the lightest of tweed jackets may be impractical in high heat. A waistcoat, shirt and tie are fine and in fact for a more casual approach lose the tie and unbutton the waistcoat if you like. You will look much better if you are dressed so you are comfortable, rather than under layers of sweat soaked tweed.

[The Wizard of BC]

If I may suggest - If you wish to wear a vest alone, look for one that has a fabric back, not the satin back with the adjuster thingy.

Vests with satin backs and adjusters are meant to be worn under a jacket. They are not meant to be outer clothing. It is pretty plain that the back is not designed to be seen.

Yes, I know, you see it done all the time. But a vest with a finished back looks much nicer when worn alone. Just an old school guy dressing thing I learned many moons ago. Like not wearing a belt and a vest at the same time. That is what braces are for. Braces hold your pants up and are worn under the vest so they are not seen.

[Taskr]

I think the waistcoat only looks quite sharp. I take Steve's advice, but also know a satin back is far more common a vest to find. Might it also be a bit cooler for warmer weather or is satin going to be less or similarily breathable? I frequent thrift shops looking for a suitable one.

[unixken]

I've often seen what Steve describes, as a "Snooker Vest". (Snooker being a game of billiards/pool.) An example of which can be seen here. Note the absense of the adjuster that Steve speaks of, and the fact that the back of the vest is a fabric other than satin. Think "Minnesota Fats."

[Steve Ashton]

There are about a gazillion styles of vest designed as outer wear.
It does not have to be one specifically for a kilt nor one seen with a suit.
Let your imagination go wild.

[Tenmiles]

I agree that a vest or waistcoat worn as outerwear definitely looks nicer if it has a fabric back, and without the adjustable strap, and that would be the preferred solution. Also, thank you, Ken, for teaching me a new term to use when shopping for one.

[Reiver]

Try a lightweight cotton vest that does not fit like a glove.
I'm in Az and we have the games coming up in Prescott (5k foot el.) but it will still be hot in May.
One must adapt.
I'll wear a 5 yard kilt during the day but a loose, blousy white shirt (LS) but rolled up. When we dine (eve) I have a nice lightweight vest that steps it up one notch.

[FinnKilt]

In the warmer seasons, if I wear an 'outer' top garment at all, it's almost always some kind of jerkin – think fishing vest but with more drop to it. Comfortable, well-pocketed, smart-casual.

In hot climates, smart-smart is basically just a terrible problem, isn't it?