Mauritius has a typical tropical climate with hot afternoons all the year round except 1-2 months. The summer months are from December to April and winters runs from May to November.
Winters are cool and dry compared to summers and thus, if you cannot bear the tropical heat, then this is the apt time for a visit.
If you are a water sports enthusiast then you may want to avoid Jan and Feb as they are peak cyclone months. Though the cyclones are not life threatening, but it can end up bringing days of rains which would be a spoiler for your vacation.
Coastal temperatures range between 25°C and 33°C in summer and between 18°C and 24°C in winter. On the plateau it will be some 5°C cooler. The highlands are also the wettest part of the island – it can rain here at any time of year, and even when it’s not raining the area can be cloaked in low-lying cloud.