India, June 2 -- This question became all important on May 26, the day the India Meteorological Department (IMD) declared monsoon onset (the monsoon at this time of the year is called the southwest monsoon) over Mumbai. As HT's Mumbai edition reported on May 27, scientists not affiliated with the IMD debated if the monsoon had indeed arrived over the city. Without knowing what the southwest monsoon is, one cannot decide who among the two is right.

So who among the IMD and non-IMD scientists is right? They both are in their own way, although it'll perhaps be prudent for the IMD to address the concerns raised by scientists elsewhere. Here is why.

The short reason why IMD was not wrong in declaring the arrival of monsoon in Mumbai is that ...