At the risk of being pedantic, that story - tragic as it is, does not evidence a movement from 15knts to 60 knots in 15 seconds, didn't say it couldn't come up quick I said, and I rely on a review of weather
stations wind records, that it will take more than 15 seconds to make that movement.
Again without wanting to get picky, I am well aware that eye witness accounts to anything, whilst getting the overall issue correct, rarely get a number of things precise, and when time is considered, it is extremely rare that eye witnesses get timings correct.
To be clear. Not saying that winds cant increase very quickly just not quadruple in 15 seconds, and when they do increase they do so with, usually, some visible warning.
That aside, these are tragic outcomes, perhaps racing
at that location or time of year will need to be considered by the ultimate coronial inquiry.