"As expected, the south-west monsoon has reached Odisha on June 13. We had predicted onset of monsoon anytime between June 13 and June 15," a senior IMD official said.
The monsoon would be activated across the state in the next three days, he said.
Today's monsoon shower has covered entire Malkangiri district and some portions of adjoining Koraput district, a statement issued by the IMD said.
Meanwhile, the IMD predicted heavy rainfall at one or two places during the next 48 hours and normal rainfall till June 22.
The state experienced a long spell of gruelling summer heat and recorded 44 sunstroke deaths this year.