Maha Monsoon The Maha Monsoon lasts from about October to January and affects the North Eastern parts of Sri Lanka with heavy rains while the South West is sunnier. This monsoon averages less rainfall than the Yala Monsoon at about 40 inches. Much like the Yala Monsoon, the temperature of the two places don't differentiate very much, however the weather does. Just like the Yala Monsoon the weather is unpredictable. It can be sunny on days that were predicted to be rainy. The average temperature for the South Western part of Sri Lanka this time of year is about 89 degrees while the North Eastern part is 81 degrees.
The Maha Monsoon brings sun to the South West beaches.