In Numakawa, Hokkaido Prefecture, the minimum temperature dropped to -7.6℃ on April 28, 2019.
It is the coldest daily minimum temperature for April 28 since records began in 1978.
https://www.data.jma.go.jp/obd/stats/etrn/view/daily_a1.php?prec_no=11&block_no=1203&year=2019&month=4&day=&view=p1