Hardy fuchsias can take a lot more sun than the tender hanging basket types.

I'm unsure if this was one of the hardy types or not. It was not a hanging basket fuchsia. It was a 'Gartenmeister'

Gartenmeister is one you often see in tubs and planters, these fuchsias with the long tubes love heat and I have seen them in plantings in full sun but they have to be introduced to full sun gradually. Another thing that might have happened, if you have it in a pot the roots could have cooked especially if the soil was quite moist. If so it would be a good idea to double pot fuchsias in these situations, in other words have a layer of dry material in between the two pots, shavings would do to keep the rootball cooler.
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Aftermidnight,

It was indeed in a pot -- no other option as I live in a 3rd floor apt.

The intro to full sun went fine.

I was thinking along those same lines as you -- that the roots may have gotten too hot. However I would have thought that keeping the soil drier would have been worse than moister soil as there would have been less evaporation to aid in cooling. (The alyssum in the pot, btw, is having a field day)

When we have a hot spell up here I try to keep my Fuchsias a little on the dry side for this reason, also it helps to keep them in white rather then dark colored pots, they don't soak up the heat as much. Being yours are on a balcony I would definitely try double potting.

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