No drop 0ff at the Portal. Look into Lone Pine Chamber of Commerce and Mt Whitney Golf Club. Easy hitch from the Portal to Lone Pine after your hike.
Very important!!!! Get good information on the snow crossing east of the tunnel above Upper Hamilton Lake. See this discussion:
Tunnel and snow crossing Rangers at SEKI will give you very conservative advice on this. Look for hikers returning from this spot with direct beta. There is usually a good discussion this time of year on High Sierra Topix.
