I just talked to a coach friend who was at the meet. Apparently the air temp was warm but then a storm came through and the rain itself was very cold and reduced the air temp to what she thought was about 18C. Some of the early events were held in dry conditions, others like the second (A-heat) of the women’s 100 hurdles on a wet track but it wasn’t raining any more. Then there was Bolt who copped the worst of it. What a run, intrinsically perhaps the best ever? It would not have been easy warming up or staying warm in such conditions and being pelted by the strength of downpour, visible in the picture link PJ highlighted, must have been distracting at best.