Mild weather all year round
Due to its heat and sunshine almost all year round, some people refer to the climate of the Dominican Republic as an "endless summer".
The climate is tropical with abundant rains. The temperature on the island remains fairly constant at around 25 degrees Celsus (77°F) throughout the year. Generally, the whole island is sunny with a tropical climate.
The change of seasons is determined more by annual rainfall than by temperature.
The months of May to October are considered the summer months in the Dominican Republic. It is generally the hottest time of the year. Highs reach around 30 degrees (87°F) during the day, with the nighttime low around 22° (72°F). But since the humidity is higher at this time of year, it may seem warmer than it actually is.
The month of May is when the island of Hispaniola receives the most rain, which usually comes in the form of short stormy bursts followed by sunshine. Annual rainfall in the Dominican Republic averages about 1473 mm (58.5 inches) per year. The western part of the country receives less rainfall than other regions, but unexpected downpours can occur anywhere on the island.
Although there is very little difference in temperature between the summer and winter months, summer on the Republic is generally low season for tourism. The island still sees a few visiting tourists, but most are here for long summer vacations. The island experiences its busiest tourist period from December to April. This is when most travelers try to escape the colder northern climate.
The fluctuation of tourism causes accommodation prices to vary depending on the season. During high season, when vacationing in the Dominican Republic is most fashionable, hotels, resorts, and restaurants raise their prices. And since the island is busiest during this popular time of year, visitors should book at least a month in advance. During the high season, the humidity is low and there is less rainfall on the island. Evenings are noticeably cooler from November to April compared to the summer months.
The higher altitude areas (Constanza, Jarabacoa), which are mostly mountainous regions in the interior of the country, experience cooler temperatures than the rest of the island. Temperatures in the mountains fell below zero, and frost was even observed on their peaks (Pico Duarte).
Like most other Caribbean islands, the Dominican Republic experiences cyclonic activity. Hurricane season lasts from early June to late November, and the island feels most of the effects in August and September.