Temporary file with specific file extension in Python 3

This doesn't work for you?

In [2]: tempfile.NamedTemporaryFile(suffix='.tif').name
Out[2]: '/var/folders/gq/swc6jtld5853skyq_xc2lpc40000gn/T/tmplrtwvxg7.tif'

did you try?

fd, path =tempfile.mkstemp(suffix = '.tif')
print(path)