Kolkata, June 19 (IANS): Monsoon in West Bengal has officially set in with the eastern metropolis receiving its first set of the seasonal rain on Friday, the Met Office said.

"Monsoon officially entered the city on Friday. Earlier, north Bengal was receiving some showers and now the entire state will witness the monsoon rains," said Devendra Pradhan, Deputy Director General of Meteorology (Eastern region), Regional Meteorological Centre, Kolkata.

"We are, however, expecting slightly less rainfall across the country this year."

He said in India, the average rainfall or the long-period average (LPA) is the average of rainfall between 1951 and 2000, which is 89 cm.

"Certain parts of Bengal may receive 100 percent rainfall but overall the average this year will hover around 90 to 93 percent with respect to the LPA," Pradhan said.

In Kolkata, the regional Met Office at Alipur recorded 2.3 mm of rainfall on Friday till 5.30 p.m. Areas in West Bengal which received rainfall on Friday include Coochbehar, Darjeeling, Diamond Harbour, Burdwan and Kharagpur.

One or two thundershowers are expected in the city on Saturday, the Met office informed, adding a low pressure has developed over Odisha-Andhra coast and it is expected to intensify into a depression in the next 24 hours.