Okay, with thanks to @MacGyver88 and @El-Guest for the final nudge regarding the 'green hat', here is the final answer...
Heat consists of 1692 symbols, delicious hesitance, headless escape, glasses, and a green hat. (6'1,4)
(NB Although in a traditional cryptic clue part of this would be a definition, the OP says in comments below that this isn't entirely the case here. Instead I think the mention of 'Heat' here is more just thematic and loosely in keeping with the final answer...)
1692 symbols: Elements 16 and 92 in the Periodic Table are Sulfur (S) and Uranium (U).
delicious: If something is delicious it makes you say 'MM'.
headless escape: The 'Escape' key on a keyboard is labelled 'Esc' - remove its head (i.e. the 'E') and you are left with 'SC'.
glasses: This is an allusion to 'OO' looking like a pair of glasses.
a green hat: With thanks to @MacGyver88 and @El-Guest, this is a reference to Luigi from the Mario computer game franchise. His green hat is emblazoned with an 'L'. (This reading is less in keeping with a traditional cryptic clue, but go with it - everything pans out...)
Altogether then, we have an answer:
SUMMER'S COOL! This phrase would fit with the fact this puzzle was posted at the start of June (the first month of summer in the Northern Hemisphere).