I arrived at Tomakomai port around 8:30PM on 30/April, and then went to Sapporo city. It was around one hour drive by highway. I went to Sapporo Kokusai Ski resort next morning. That ski resort is located in Sapporo city, but I reached ski resort after one hour drive. Sapporo city is too huge.
It felt like early summer in Sapporo, but there was still a lot of snow in the mountains. I could go all ski runs in Sapporo Kokusai ski resort. It was amazing.