This April seems to be the second coolest after 2012 in the last decade for Delhi and NCR. Until April 21st, there was only one occasion when Delhi has surpassed the 40-degrees mark. On April 15th Delhi recorded a maximum temperature of 40.1 degrees. In 2012, the maximum of Delhi reached 38.7 degrees that was on April 4 in 2012.
If we consider the maximums between 2009 and 2019, they were more than 40.1 degrees except 2012 when it was less than 40 degrees.
The reason for this cooler temperature during this year could be attributed to the high frequency and intensity of Western disturbances. Western disturbances induced cyclonic circulation over Rajasthan and northern Plains, which lead to frequent rain and thundershower activities.
One more Western disturbance is expected around April 27. These Western disturbances will ensure that northern Plains including Delhi and NCR will continue to get some weather activity. Either rainfall, dust storm or thundershower. The weather activities will not allow the maximum temperature of Delhi to increase much and will remain in mid to higher thirties.
Therefore, there are bright chances that 2020 will end as a second coolest April in the last one decade.