in the past 2 hours the temperature has gone from 17 (62F) to 27 (80F)
& I'm heading out to a friend's place for lunch soon ...

hmmm, if it's 27C at 11, what will it be mid afternoon?

Sydney forecast - Mostly sunny. Light winds becoming easterly 15 to 25 km/h in the early afternoon then becoming light in the evening.
Large and powerful surf conditions are expected to be hazardous for coastal activities such as rock fishing, swimming and surfing.

I'm sure the beaches are full & the (volunteer) lifesavers will be there, too, on many of them, but unfortunately not every beach.

sandra