September Weather in Puerto Rico





The tables below give the normal September temperatures and rainfall for cities and popular vacation spots in Puerto Rico. There's also information here on hurricanes, plus this month's average humidity and ocean temperature.

The temperature and rain measurements are averages based on weather data collected from 1991 to 2020 for the US National Centers for Environmental Information.

One site, Pico Del Este, is much cooler than others on the list. That's because it's a high mountain peak, at 3448 feet (1050 metres) elevation, in the El Yunque Caribbean National Forest.

Temperature

Average September temperatures in Puerto Rico
High °F Low °F Place High °C Low °C
89 73 Aguirre 31 23
81 68 Aibonito 27 20
90 70 Caguas 32 21
89 76 Ceiba 32 25
87 73 Dorado 30 23
90 77 Guayama 32 25
87 73 Isabela 31 23
89 72 Juncos 31 22
91 76 La Parguera 33 25
91 70 Lajas 33 21
89 75 Levittown 32 24
87 72 Manati 31 22
80 67 Maricao 27 19
90 72 Mayagüez 32 22
92 72 Mona Island 33 22
72 64 Pico Del Este 22 18
91 69 Ponce 33 20
89 78 San Juan 32 25

Ocean Temperature at San Juan, Puerto Rico averages 83 degrees Fahrenheit (28 degrees Celsius) in September.

Rainfall

Average total precipitation in September. Days are when it rains at least 0.01 inches (0.25 millimetres).
Days Place Inches Milli­metres
10 Aguirre 6.9 174
15 Aibonito 9.4 240
19 Caguas 8.7 221
18 Ceiba 6.4 163
15 Dorado 6.5 165
16 Guayama 7.3 185
16 Isabela 6.7 171
16 Juncos 8.7 222
La Parguera 5.5 140
13 Lajas 5.7 144
Levittown 8.1 206
14 Manati 5.7 144
Maricao 11.6 295
15 Mayagüez 6.6 169
11 Mona Island 4.7 120
12 Ponce 6.9 176
18 San Juan 6.5 165

Relative Humidity at San Juan, Puerto Rico in September averages 79 percent in the morning and 67 percent in the afternoon.

Hurricanes and Tropical Storms

September is the height of hurricane and tropical storm activity for Puerto Rico. All areas of the country could be affected by severe weather.

Overall, the chance of a tropical storm or hurricane getting within 100 miles (165 kilometres) of Puerto Rico this month is 20 percent. There's an eight percent chance of a hurricane and a 1 to 2 percent chance of a major hurricane.

References

NOAA National Centers for Environmental Information (NCEI). Climate Normals.

National Oceanographic Data Center. NODC Coastal Water Temperature Guide (CWTG).

NOAA. National Weather Service. National Hurricane Center.

Puerto Rico
Temperature & Rainfall
Back to Top