The Dominican Republic climate is influenced by the Atlantic Anticyclone that regulates the flow of the trade winds and by the humid tropical air that produces most of the rain: the seasonal tendency of the rains is closely related to the flows of the trade winds and to their pattern when reaching the mountain systems of the island.

The Trade Winds first  reach the North-east of the Dominican Republic from the Atlantic Ocean: as soon as they collide with the northern slopes of the mountainsa s the clouds condense their moisture load produces so-called orographic rains. This occurs first in the "Cordillera Septentrional " and in the "Sierra de Samaná", later in the central ans southern higher mountains  such as the "Cordillera Central".

Mountains in the Dominican Republic ( Atlas 2012 Ministerio de Medio Ambiente RD)

The map below shows the average level of rainfall in the Sosua area: it is on average between 1200 mm and 1600 mm per year.

Average yearly rain level  in the Dominican Republic (Atlas 2012 Ministerio de Medio Ambiente RD)

The part of the Noarth coast where Sosua is located does not have mountains high enough to attract and clock the trade winds loaded with moisture so they tend to discharge to the South of Sosua in the mountains that divide the province of Puerto Plata from that of Santiago.

Sosúa receives an annual rainfall level that places it halfway between the most arid and wettest regions, a particularly favorable area with enough water resources to support the rich nature, wildlife and human needs and at the same time time an area with ideal weather conditions for vacationers.

The monthly distribution of rainfall in Sosúa follows a seasonal model: the highest level of rainfall concentrated in the winter months of November and December (these months have approximately 35% of rainy days with sporadic and non-continuous rain on the same day) while the summer period is the driest.

Livello medio delle precipitazioni per mese nella città di Sosua

Ttemperatures are typically seasonal too: the coldest months of Sosúa are the winter months with average temperatures of 24° (75F), highest temperature in the daytime between 27° (80F) and 33° (91F) and nighttime temberatures between 14° (57F) and 18° (64F). Summers in Sosua are really warm with average temperatures of 27° (80F) and highest daytime  temperatures between 32° (90F) and 40° (104F) while the lowest nighttime temperatures are between 19° (66F) and 22° (71F).

Average monthly temperatures in Sosua (Celsius degrees)

Highest and lowest monthly temperatures in Sosua (Celsius degrees)

The temperature of the water in Sosua is clearly influenced by the atmospheric temperature with ocean water in Sosúa hot throughout the year and never falling below 25° (77°) . During the summer months the water temperature can be as high as 28° (82F).

Monthly average water temperature in Sosua (Celsius degree)

Humidity levels are constantly high throughout the year with the driest months in summer and the rainiest months in winter:

Humidity rates in Sosua

During the hot summer months characterized by high atmospheric and oceanic temperatures the formation of tropical storms is likely: these following the route of the Trade Windss can sometimes turn into hurricanes and reach the North coast of the Dominican Republic although the probability of direct impavt is quite low. In the last 25 years, 5 hurricanes have passed close to the North coast of the Dominican Republic but none of them has made a direct landfall on the coast, they have all  passed at least 50 nautical miles from the coast thus greatly reducing the costs and damages caused by their passage. The central part of an hurricane is called the eye of the hurricane and there blow the strongst and most distructive winds: a direct landfall of the eye of an hurricane produces far more damages than a close by passage.

These are the hurricanes that have passed close to Sosua since 1995:

Hurricane Debby, August 2000

Hurricane Jeanne, September 2004

Hurricane Irene, August 2011

Hurricane Irma, September 2017

Hurricane Maria, September 2017

It is impossible to predict the probability and frequency of such phenomena: since 2011 for 5 summers there were no hurricanes close to Sosua, while in 2017 two strong hurricanes formed in the same month and they both passed close to Sosua but not close enough to produce significant damages.  

These are the trajectories followed by the 5 hurricanes wich passed close to Sosua over the last 25 years:

Hurricane Debby,  August 2000

Hurricane Jeanne, September 2004

Hurricane Irene,  August 2011

Hurricane  Irma,  September 2017

Hurricane Maria,  September 2017

At the beginning of September 2017, I was able to personally witness the passage of Hurricane IRMA, which was considered the most powerful of the last 100 years: thanks God the center of the hurricane passed almost 50 nautical miles off the north coast of the Dominican Republic without causing serious damage.

Here are some videos I filmed in Sosua during the passage of hurricane IRMA.