I was in Darjeeling for 6 days, but never had the chance to see Tiger Hill. Each day; I woke up to rain or fog. Not sure if other times of the year are more reliable for clear weather. Since you have to get up around 4 or so in the morning (to go down the hill, find a share-taxi, drive out to the hill) to get to the hills before the sun rises, it can be tricky guessing if 4 a.m fog will equal 6 a.m fog, or, if everything will clear up by the time you get to the hill. (Ah well; just a good reason for me to return in the future.).

Since the weather does change quickly and dramatically in Darjeeling, it's great that--at the top of the town--you can easily get to stunning viewpoints within 5 minutes, when the weather does clear up.

it is amzing. travellers reach their at 4 am to see the sunrise over kanchenjunga (the himalayas)...the snowcovered peaks resembles a golden crown when the rays touch it at that hour...u have to be really lucky to witness that moment. i have been there twice but could view the spectacle just once when i was young. secondly, i love the snowfall there...it is so serene up there that u seem completely cut off from the world. up there i found a dog who was more than willing to pose with me

Sunrise at Tiger Hill is a must if you are in Darjeeling! IT is a real experience, filled with local tourists and chai vendors and views of the Himalaya. On a clear day you can catch glimpses of Mt. Everest and Kanchenjunga. 

Be sure there is no fog the day before you go there :)