Weather has played an important role in governing the lives of Maldivians from time immemorial. This is not surprising of a nation with less than one percent land and over 99 percent sea. Since ancient times, Maldivians have organized their lives based on a system on periods referred to as ‘nakaiy’, each of which is 13 or 14 days long and is divided into two seasons; the ‘Iruvai’ (north-east monsoon) and ‘hulhangu’ (south-west monsoon). The nakaiy calendar was and is still used to determine such things as the best time for fishing, travel or planting crops. The Maldives has a tropical climate with the weather mainly determined by the monsoons.
The south-west monsoon or ‘hulhangu’ lasts from May to September and is the wet season. The seas are moderate to rough and strong gales occur during this period. Cloudy days are more frequent. During October light winds are experienced more frequently and by the end of November, the transitional period begins, with the winds shifting from W-NE to N-NE.
The northeast monsoon ‘iruvai’ begins from December and lasts till April, bringing a period of clear skies, lower humidity and very little rain, the hottest month on average being April and the coolest, December. The relative humidity is only 5% lower than during the south-west monsoon
Strong prevailing winds blow from SW-W-WN during the south-west monsoon and N-NE-E during the north-east monsoon.
The warm temperatures last year round with plenty of sunshine and due to the warm tropical climate, variations in daily temperature are relatively minor throughout the year. This can be seen from the weather recorded over a 24 year period between 1967 – 1990, in which the hottest month on average was April, with a maximum monthly mean temperature of 31.5°C and a minimum of 26.5°C. The coolest month was December, with a maximum monthly mean temperature of 29.8°C and a minimum of 25.3°C.
Even though the temperature varies only slightly, there is a significant variation in the monthly rainfall levels. Whereas May and October records the highest average monthly rainfall, February is the driest with January to April being relatively dry. In April, calm, windless days are more likely to be experienced than in any other time of the year. The transitional period between monsoons begins in April and by the end of May, usually after a fortnight of strong winds and rain, the change of season occurs with the wind direction of W-SW.
However, there still exists a considerable variation of climate between Northern and Southern atolls in the Maldives. In the south the rainfall is greater and so are the number of rain days. Showers are not as heavy as in the North and as the seasons are more evident the further away the atolls are from the Equator, the northern atolls experience the extremes of temperatures.
The Maldives lies in the equatorial belt and making severe storms and cyclones extremely rare events. However the country experiences rough weather and heavy seas from cyclones and other storms that form in the Bay of Bengal or the Arabian Sea.
December – April NE Monsoon
April – Transition Period
May – November SW Monsoon
November – Transition Period
Currents & Water Temperatures
Maldives experiences strong oceanic currents which are largely influenced by the direction of the trade winds. Currents in channels near the capital Male’ have been recorded at four knots or more. Inside the atolls, current speeds are more settled tidal currents, which flow according to the height of the tide and direction of the prevailing winds, are found to be weaker than the oceanic currents, though they cause velocity variations in the flow.
On the eastern side of Male’ atoll, currents predominantly flow into the atoll during the north-east monsoon. The opposite applies to the western side of the atoll. This is by no means the rule, as changes in the wind direction and tides can offset the influence of the oceanic currents. If the winds ease off for a few days, then currents are more likely to flow both in and out of the channels.
During the transitional month of April and November, when the wind direction and oceanic currents are less predictable, current is more likely to be influenced by the tides and similarly flow both in and out of the channels.
At atoll passages, current streams can be quite irregular due to the islands, reefs and sandy shoals.
The ocean water temperatures rarely vary beyond 27 – 30° C although thermo clines can sometimes be experienced at depths below 20 meters. During warm temperatures, water temperatures inside the lagoons builds up affecting the water temperatures inside the atolls in turn, enabling divers to comfortably dive without a wet suit.
During rainsqualls and heavy winds, extra clothing needs to be available to dress up in the boat after dives. Lycra and 3mm wetsuits are the most popular in tropical waters but if multiple dives are to be performed within the day, 5mm suits would be more appropriate.