Bahar means 'spring' in Urdu, and a series of related ragas (or 'raags') in North Indian classical music are called Bahar, Basant (Sanskrit for 'spring') and by other related names. These are light-hearted, extrovert ragas suitable for the spring season.
Bahar or spring is a key image in Sufi poetry. Springtime is the time of love and intoxication, and Sufi poets run the variations on the love of Allah bringing welcome refreshment to the dry, parched soul of the unregenerate human being. In this well-known qawwali, "Fasle Gul Hai," the great Pakistani qawwali singer Nusrat Fateh Ali Khan invites the listener to join in the intoxication of spring: "It is the season of flowers, intoxicate yourself. . . If there is no wine then drink the tears of suffering, but drink as these are the days of spring." For the full text and translation see here.
There is also a performance of raga Bahar in qawwali style by Nusrat Fateh Ali Khan on Youtube here.
The Pakistani singer Tina Sani sings 'Bahar aai to jaisay,' a ghazal about the coming of spring written by the renowned Urdu poet Faiz Ahmed Faiz.
With the coming of spring, once again
it's like they have returned from non-existence
all those thoughts, all that youthfulness
which had sacrificed themselves upon your lips
which had always sprung up again after their sacrifice
. . .
With the coming of spring
all the accounts are open afresh