Green’s Dictionary of Slang

gale n.

in context of laughter, a large quantity; a general intensifier.

[UK]E.Pugh Cockney At Home 65: All was bliss and sweat and noise in a gale o’ giggles and gargle.

In phrases

on a gale

(US) having fun.

[US]Nat. Police Gaz. (NY) 2 Dec. 7/3: ‘[T]hese two come tearin’ down [...] with lots ot gigglin’ and carryin’ on. [...] They were on a gale, and it was all in fun’.