Forgive me if I tell you what you already know, but the Grandiflora classification under which we find Tigress is not recognized outside the US and Canada. So in other places you may find it listed as a hybrid tea.
This rose hasn't done very well for me. I live in the desert southwest and we don't have problems with too many diseases but this plant has managed to get some anyway. It doesn't have very full foliage or produce many flowers.
I live in Reno, Nevada and I'm wondering if I can go ahead and plant this rose in my garden even if the temperatures are in the mid-90s or should I wait until Fall?
High heat puts most roses under some stress even if they are planted in the ground. Cool weather is a better time to plant a rose as you don't have to worry about keeping it alive.