Photo taken on Oct. 31, 2019 shows a snow-covered road sign on the Sljeme mountain in Zagreb, Croatia. A sudden temperature drop and snowfall hit the area on Thursday following above-average temperatures for most of the month in the Croatian capital. (Igor Soban/Handout via Xinhua)

Workers repair a snow-covered cable car at a ski resort on the Sljeme mountain in Zagreb, Croatia, Oct. 31, 2019. A sudden temperature drop and snowfall hit the area on Thursday following above-average temperatures for most of the month in the Croatian capital. (Igor Soban/Handout via Xinhua)

Photo taken on Oct. 31, 2019 shows snow-covered cable cars at a ski resort on the Sljeme mountain in Zagreb, Croatia. A sudden temperature drop and snowfall hit the area on Thursday following above-average temperatures for most of the month in the Croatian capital. (Igor Soban/Handout via Xinhua)

Photo taken on Oct. 31, 2019 shows snow scene on the Sljeme mountain in Zagreb, Croatia. A sudden temperature drop and snowfall hit the area on Thursday following above-average temperatures for most of the month in the Croatian capital. (Igor Soban/Handout via Xinhua)

Photo taken on Oct. 31, 2019 shows snow-covered cable cars at a ski resort on the Sljeme mountain in Zagreb, Croatia. A sudden temperature drop and snowfall hit the area on Thursday following above-average temperatures for most of the month in the Croatian capital. (Igor Soban/Handout via Xinhua)