Explanation:

Causes in the delay of monsoon:

• The Madden-Julian Oscillation (MJO) is an eastward moving disturbance of clouds, rainfall, winds, and pressure. It circles the planet along the tropical belt in 30-80 days. During its global ride, it intensifies over three regions - the eastern Indian Ocean, south of the maritime continent and the western Pacific Ocean and transfers a part of its energy to the underlying ocean. MJO is a low-pressure system that facilitates cyclone formation over the Indian Ocean increases the temperature of the Indian ocean and thus lowers the high pressure, which delays the monsoon.
• The formation of a cyclone during the monsoon season usually indicates warmer-than-usual sea surface temperatures which means that the temperature difference between land and sea was reduced.
• This could also cause the monsoon winds which specifically depend upon this difference to not move forward.
• El Nino is the abnormal warming of sea surface temperature (SST) of the Pacific Ocean off the coast of Peru in South America, which reduces the development of high pressure on the Indian ocean and weakens the monsoon hence, El Nino leads to deficit rainfall and delay in the onset of monsoon.
• Western disturbances delay the heating of Indian landmass which leads to the development of weak low pressure on the Tibetan plateau which causes a delay in the monsoon.