Warm is a word that could be used to describe the New Delhi weather. The city’s climate is a humid subtropical one, so you certainly shouldn’t expect to encounter a lot of snow and ice, even during the middle of winter. In fact, many winter days in New Delhi see the temperatures hovering somewhere in the 70's. As for rain, the monsoonal season is the wettest time of year. This season runs from June to September. July and August are particularly wet months in New Delhi.
Summer in Delhi: In general, summer in India runs from April to June. It is a very hot season for much of the country. In fact, if you aren’t spending time in the lofty and cooler Himalayas region, your summer visit to India is likely to see you seeking out air conditioning like never before. May and June are particularly hot in New Delhi, boasting average highs of around 102 degrees, and both April and July tend to see daytime temps around the 95-degree mark. It doesn’t get much cooler in September or October. For this reason, some say that summer in New Delhi runs from April to October.
Fall in Delhi: Autumn in New Delhi is basically two seasons in one. There is early autumn, which is characterized by high daytime temps and a relatively healthy chance of rain, and late autumn, which is both cooler and drier. The first half of autumn tends to see the daytime temps reaching into the 90's, while daytime temps in the 80's are more common in late autumn. Average lows range from 75 to 55 degrees, so it can get pretty cool.
Winter in Delhi: Winter is widely considered to be the best time to visit New Delhi. This has everything to do with weather. While enjoying sightseeing tours during the day, visitors don’t usually have to contend with overbearing heat, and the chance of rain is rather low. It often gets cooler at night, so packing a scarf and a sweater can be a good idea. The average high temperature for New Delhi in the winter is somewhere around 75 degrees, while the average low is about 50 degrees.
Spring in Delhi: The spring is somewhat hard to define in New Delhi. The winter season, for example, has tendencies that many people would label as being spring-like. Also, the high temperatures of April, May, and June are more akin to what you would expect out of a summer season. Basically, you could argue that the New Delhi spring really only includes the months of February and March. The average high is around 75 degrees for February and 85 degrees for March. These are two of the driest months of the year, so rain shouldn’t put a big damper on things.