jatin1726
probably not very easy to do...
my guess is that you would have to use the Geolocation plugin to get the user's location, build a request string to send to one of the weather APIs using AJAX and then parse the response. (some return XML or jSON)
You would have to set up an account at one of the weather APIs - some are free but limit the number of requests you can make, others are a paid service.
get your API keys, some make you whitelist your app - which can take days. Generate an oauth signature...
The only thing similar I have done is use the google maps api to get mileage between two addresses. It was for a business app used at the company I work for and only used by a few people, so I didn't have to worry about limits and commercial restrictions.