Two days of cross-country skiing in the last days of December in Iran. On the first day, athletes were really...really slow, even much slower than what one might expect from Iranian cross-country skiers (the winner of the women's race competed at the 2017 world championships and though she didn't come close to qualifying, she was not an eternity behind or something).
https://www.fis-ski.com/DB/general/event-details.html?sectorcode=CC&eventid=44702&seasoncode=2019
On the second day however, both men and women were incredibly much faster. As in, more than 20 minutes faster than their time over the same distance a day earlier. That's not normal, especially for relatively experienced athletes like the women's winner. So, @MHSN, any idea what could have happened? Was there some sort of horror blizzard from hell on 30 December and perfect weather on 31?