New Delhi Natural Environment

New Delhi is an example of extreme climate. If you are planning a visit you must consider the time you are planning to land here. The best time to come here is between February and May and then again between October and November. December-January is cold and foggy and June is very hot (50 C) and July-September is humid and hot. Its also a good place to base your travel to places like Agra, Jaipur if you are keen for a day trip.

The crowded, colourful and unruly heart of India. Don't let your first impressions of Delhi stick like a sacred cow in a traffic jam: get behind the madcap façade and discover the inner peace of a city rich with culture, architecture and human diversity, deep with history and totally addictive to epicureans. Both Old and New Delhi exert a beguiling charm on visitors. Lose yourself unwinding the secrets of the city's Mughal past in the labyrinthine streets of Old Delhi before emerging into the wide open spaces of imperial New Delhi, with its ordered governmental vistas and generous leafy avenues. Summer in Delhi is no joke - from April the temperature climbs relentlessly to more than 45°C (113°F) in May and June and the heat doesn't really abate until October. Dust storms called loo sweep in from Rajasthan with considerable fury. The arrival of the monsoon, at the end of June, brings intense humidity - the murder rate usually peaks in this month. From November to March is the best time to visit, with cool but sunny weather. Also, Holi, one of the most exuberant Hindu festivals, takes place around this time, in February or March. October sees the end of the monsoon, but is reasonably pleasant, although the days can still be pretty hot. Nights can be quite chilly in December and January. Weather One of Delhi's drawbacks is that for more than half the year the climate is lousy. For about four months - from November until about March - it's fine, with daytime temperatures between 21 and 30°C (70-86°F). However, by the end of April it's hot, while May and June are really hot - temperatures can swoop up to more than 45°C (113°F). In July it gets cooler but the humidity really hits, often with all-day rain through August and September.

The best time to go to Delhi is after the monson season, around october. The weather is cool and you can visit the most important sites in the morning before 12:00 am

i live in delhi so i can pretty much be very confident about the place...
theres no point explaining stuff thats easy enough to know from any website...
a few unknown sites  once youre done with the usual sights, make it a point to check out these lesser known gems
~hauz khas madarsa- if you liked lodhi gardens (which you would), this place is right up your alley. a hep market leads you to the ruins of madarsa which stand by the side of a medieval tank, in the midst of a lush park... romantic enough... ~crafts museum- this is an amazing place... well designed... nice galleries, a great souvenir shop... nice way to spend half a day ~dont just stare at chandni chowk and leave. take a walk through. you wont be mortally dangered in any way. but you'll have an experience to remember.and you can have great bargains and food on the way. ~near connaught place, on hailey road, is a stepwell by the name of agrasen ki baoli. contrast galore, as standing at the top of the ancient steps, you can get a view of both, the historic stepwell and the modern skyscrapers of cp... and its probably the coolest (climatically) spot in the city centre
let downs- ~personally, red fort is somewhat disappointing. for all its hype, red fort is pretty... well, normal. it is impressive, but not enough. there are better forts in the country. ~paranthe wali gali- you can get better and cheaper paranthas at the newer and swankier parantha joints like not just paranthas, without having to heave yourself to chandni chowk. ~akshardham- plastic. it all seems like a huge publicity stunt. you dont feel any sacredness whatsoever. more like bhaktiland-the disneyland of faith. the food court is decent though.
on the mark ~humayun's tomb, lodhi gardens, safdarjung's tomb, mehrauli- all are monuments that will definitely awe you. ~lutyens' delhi- a drive through and you'll know exactly why this is the country's most expensive piece of real estate ~big chill-desserts are not overhyped at all... id call it underhyped... head here for gastronomic orgasm