The weather in Flores like the rest of Indonesia tropical and based on a wet and a dry season that alternate every year. Indonesia's area is so vast and includes so many islands that it is impossible to deal with the entire country in isolation as there are equatorial mountains in Iran Jaya and Papua that are actually snow capped which differ greatly in climate and weather patterns to the sun kissed beaches of Bali. Thankfully the weather in Flores is practically good with extended dry season weather and with close proximity to the coast, there is often a cool breeze.
The Wet season is commonly between November and March leaving April to October to the dry season. This is a general guideline which can shift depending on local and large weather patterns meaning that the transition periods between the seasons can shift, this may be something you wish to consider if booking a holiday in the transition periods. West Manggarai has a climate classified as tropical and semi-arid meaning that there are tendencies in the dry seasons for water to become extremely scarce, in Flores this is due to a combination of extremely low rainfall throughout the dry season, a very high evaporation rate, rain blocking and mountain ranges. This dry arid climate extends to the surrounding islands and along Flores coastline where rainfall is also very low.
West Manggarai is also influenced heavily by the monsoon winds that can bring dry or wet weather depending on the time of year and the origin of the winds. Between April and October in the dry season, dry winds from the southeast monsoon pass over the region. Between November and March salvation blows in from the northwest in the form of large and heavy amounts of rain.
Flores' climate also differs depending on where about you are and in what kind of terrain you are in. for instance West Flores in a similar way to the rest of Flores and indeed Indonesia there are a string of high mountain ranges situated very close to the beaches. As you move higher in altitude the climate will become cooler and more humid which can be extremely refreshing and is an excellent compliment to the incredible views from these points, mist and fog can cling to the mountains that hydrate the forest landscapes that are cool sheltered and extremely humid.
West Flores climate and differences n weather are inline with the rest of Indonesia, the main difference being the longer and more severe dry season, during this period the weather is more comfortable due to the lack of humidity but water supplies and droughts can cause major issues particularly in the in the west Manggarai area. If you wish to travel to these regions then please observe and respect this problem by keeping water use to a bare minimum. Do not however let these extremities put you off a visit to this magnificent and beautiful area as the weather is manageable and it is always possible to buy bottled water.