2 nights in Nagano sufficient?

I will be spending 2 nites in Nagano. Is it sufficient to cover most area in Nagano, Matsumoto, obuse and takayama.? How is the summer weather? Thanks

It depends on where you start for Nagao from but I think two nights might be Ok for covering Matsumoto, Nagano and Obuse. However, Takayama is a bit apart from those places. One more night's stay will make it sufficient. Summer is perfect time to visit.

I will be spending 2 nites in Nagano. Is it sufficient to cover most area in Nagano, Matsumoto, obuse and takayama.?

Two nights can be as little as a single day or as much as three full days depending on where and when you start and end day 1 and day 3.

In order to see Nagano City, Matsumoto, Obuse and Takayama, I recommend at the very least three full days on site, not including access to Nagano/Takayama. Slow travelers better allocate a minimum of four days.