Calcutta's rainiest month has so far recorded a 23 per cent rain deficit in the city.

But after a hot and sultry week, the Met office has finally forecast rain in Calcutta from Wednesday.

Calcutta received 186.5mm of rain from July 1 to 20, compared with the usual quota of 240.8mm during the same period.

July is usually the rainiest month of the monsoon. The usual July quota of rain for Calcutta is 396mm, followed by August’s usual quota of 344.5mm.

The monsoon currents are expected to be active over south Bengal over the next few days, leading to a wet spell in Calcutta, Met officials said.