Never been that cold, but lived in a town where winter lows were in the teens ( 15C was cold to us), and we often had upcountry visitors come and drop dead from heatstroke, in winter. The average day was sunup 15-20C, 8AM 25C, 10AM 30C and at 1PM 40-42C, dropping to 40C at around 7PM. We would drink around 50l of water in the shop each day, for a shop of 10 people, not counting the water for teatime.
When our aircon detonated one fine summer's day and left pieces all over the roof and the concrete apron we were regularly measuring temperatures above 60C indoors.