This paper is the first to estimate the causal effect of extreme temperatures on time reallocation from a gender perspective. To this end, I exploit exogenous variation in temperature over 12 years within Colombian municipalities. I find that men increase the time allocated to childcare by around 13.4% in the presence of children ages 0 to 5, and by 8% in the presence of children ages 6 to 11 when exposed to heat waves. Meanwhile, women's time is unresponsive to extreme temperatures. The results suggest that men reallocate time from paid labor to childcare when exposed to extreme heat since fatherhood is leisure-based while motherhood is still deeply linked to routine care. Given that recreational activities are not a substitute for routine care, the increase in men's childcare hours does not reduce women's unpaid work load.