Yeah, something like being able to know when over the course of the summer, say perhaps 3 months, temperatures in Miami are warm but not excessively hot. I really like to travel at the tails of top season for this reason, but that's really just a proxy in place of knowing the above.

Lonely Planet offers something like this [1], but it would be nice if the data were more granular than one high/low for each month and data sources were more transparent.

[1]: http://www.lonelyplanet.com/usa/miami/essential-information