Río San Juan Temperature by Month

The average annual maximum temperature in Río San Juan, Puerto Plata Province, Dominican Republic is 29°C (84°F), with little variation between seasons. This page covers monthly averages, day-night differences, and how Río San Juan compares to cities worldwide.

The temperature in Río San Juan changes very little across the seasons, maintaining a similar climate throughout the year. Maximum daytime temperatures range from a comfortable 27°C (81°F) in January to a very warm 31°C (88°F) in September. Nighttime lows range from 25°C (77°F) in September to 22°C (72°F) in January.

The chart below illustrates the average maximum day and minimum night temperatures in Río San Juan by month:

Daily lows are most common between 4 AM and 6 AM. By 3 PM temperatures reach their daily high, driven by peak solar heating.

The chart below shows the average temperature throughout the year:

Río San Juan's average annual maximum temperature is 29°C (84°F). To put that in context, here's how it compares to a few well-known destinations:

Athens, Greece sits at 23°C (73°F) on average, with hot dry summers and mild winters characteristic of the Mediterranean.

Zermatt, Switzerland averages just 4°C (39°F) annually due to its altitude, with very cold winters and cool summers even at its warmest.

Buenos Aires, Argentina averages 23°C (73°F) a year, with hot summers and mild winters, and seasons reversed compared to Europe.

Melbourne, Australia averages 20°C (68°F) annually, known for unpredictable weather, with four seasons sometimes happening in one day.

Temperature alone doesn't tell the whole story, humidity plays a big role in how warm or cold it actually feels. High humidity in summer makes the heat feel more intense, particularly once temperatures climb above 25°C. In winter, the same humidity can make cold air feel sharper than the thermometer suggests.

In Río San Juan, January is the coolest month, with average highs of 27°C (81°F) and humidity around 84%, considered very high. In September, the warmest month, temperatures average 31°C (88°F) with 78% humidity, conditions that feel high. For a full picture, see our humidity page.

Climate temperature data is typically calculated as a 30-year average. This smooths out year-to-year variability and gives a more reliable picture of what a place is actually like, rather than what happened in any single unusual year.

The readings come from a range of sources, land-based weather stations, ocean buoys, ships, and satellites. That data is collected by weather services around the world, then pooled, quality-checked, and averaged to produce the climate records you see here.

For cities and regions with significant elevation, altitude is one of the biggest factors shaping local temperatures. As a rule of thumb, temperatures fall by around 6°C for every 1,000 metres gained, so a city at 2,000 metres will typically be around 12°C cooler than a city at sea level in the same region. Higher ground also tends to see more dramatic day-to-night temperature swings, since thinner air loses heat faster after sunset.

For more on Río San Juan's weather, including monthly rainfall, sunshine hours, and humidity, visit our Río San Juan climate page.