Don't get your hopes too high about Tokyo World Championships marathons. Forecast for women's marathon, partly sunny:
8:00 start: 28˚C, 76% humidity, heat index 32˚C
1 hr into race: 30˚C, 72% humidity, heat index 36˚C
2:20 into race: 31˚C, 67% humidity, heat index 37˚C
