Finally the news that everyone had been waiting for is official; and it has been long overdue. Rohtang Pass was first declared open in early April and since then; the speculations were that the Manali Kaza route too would get open in April itself. But then the spell of late snowfalls throughout the month of April and May changed everything. Rohtang was opened and closed multiple times and no one knew by when it will finally be declared open completely for tourists. The word however now is official. Finally Manali Kaza road opens for tourists and HRTC too resumed its Manali to Kaza bus service.
Tourist season actually never really ends in Spiti valley. Of the two roads connecting it to the rest of the country; the road from Shimla remains open throughout the year. There could be times when the road many get blocked if the weather turned extreme and it snowed heavily but even then; the authorities clear it just as soon as they are able to. So you can actually be there in all 12 months. The road from Manali however remains open for only about 5 months a year after Rohtang and Kunzum Passes have been freed of snow.
Manali Kaza Road Opens
But in many ways, it is actually the Manali Kaza road that marks the beginning of tourist season in Spiti as well when it gets declared open. Much of it I think attributes to the fact that this is the only time when Spiti circuit can be completed; or else you would have to go back to Shimla from Kaza.
Please be advised however that the road condition right now is not at its best. There is about 2 to 3 feet of snow at Rohtang top; and the snow walls at several places are up to 10 to 15 feet high. Please practice caution if you are planning to drive on your own to Spiti valley via Manali.
I hope the information above was of help. If you have any further questions; please feel free to ask in the comment section below and I will be glad to answer. Alternatively, you can also post a query at our Community Forum and either I or any other member would assist in any way that we can.