September weather forecast
Puerto Rico, USA

September in Puerto Rico marks a critical phase in the meteorological calendar, as it's historically one of the most active months for hurricanes. Temperature-wise, the island retains its summer warmth with minimums around 77°F (25°C) and highs that can touch 90°F (32.2°C). While the temperature variance from August is minimal, the atmosphere remains charged with tropical humidity.

The northern zones, including regions like San Juan and Bayamon, consistently exhibit slightly cooler climates compared to the warmer southern areas. The relief provided by the Cordillera Central Mountain Range remains evident in towns like Ciales and Aibonito, though the distinction between coastal and mountainous temperatures becomes more nuanced during this peak period.

In September, rainfall continues to play a major role in the island's weather. The established rhythm of calm mornings followed by robust afternoon rains continues, but there's an added intensity given the month's climatic predisposition. Coastal towns, from Aguadilla to Fajardo, remain at the intersection of this moist, heated confluence, encapsulating a true tropical experience.

The overarching theme for September, however, is the heightened risk of hurricanes. Given the month's historical track record, the entire Atlantic basin, including Puerto Rico, remains particularly watchful. The island's strategic location makes it a potential target for these massive storm systems. Thus, preparations, vigilance, and awareness reach their peak during this period to ensure the safety and well-being of its inhabitants.

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• San Juan - September »
  In San Juan in September, the average water temperature is 84.9°F (29.4°C). With an average ocean temperature of 84.9°F (29.4°C), September is the month with the warmest seawater in San Juan.
• Fajardo - September »
  In Fajardo in September, the average water temperature is 84.9°F (29.4°C). In Fajardo in September, it is raining for 19.6 days, with typically 1.77" (45mm) of accumulated precipitation.
• Toa Baja - September »
  In Toa Baja during September, the rain falls for 20.4 days and regularly aggregates up to 3.62" (92mm) of precipitation. As September arrives, the weather in Toa Baja remains consistent with the previous month.
• Aguadilla - September »
  The month with the warmest seawater in Aguadilla is September, with an average ocean temperature of 84.9°F (29.4°C). With an average ocean temperature of 84.9°F (29.4°C), September is the month with the warmest seawater in Aguadilla.
• Vega Baja - September »
  In Vega Baja during September, the rain falls for 19.5 days and regularly aggregates up to 3.94" (100mm) of precipitation. The average sunshine duration in September in Vega Baja, Puerto Rico, is 9.4h.
• Juana Díaz - September »
  September is the month with the warmest seawater in Juana Díaz, with an average ocean temperature of 85.3°F (29.6°C). The average high-temperature in Juana Díaz during September registers at a warm 85.8°F (29.9°C), closely corresponding to the preceding month.
• Adjuntas - September »
  The month with the most rainfall in Adjuntas is September, when the rain falls for 20.9 days and typically aggregates up to 3.58" (91mm) of precipitation. The month with the most snowfall days in Adjuntas is September, when snow falls for 0.1 days.
• Cabo Rojo - September »
  The month with the most rainfall in Cabo Rojo is September, when the rain falls for 21.7 days and typically aggregates up to 3.58" (91mm) of precipitation. In Cabo Rojo in September, during 21.7 rainfall days, 3.58" (91mm) of precipitation is typically accumulated.
• Guánica - September »
  The month with the warmest seawater in Guánica is September, with an average ocean temperature of 84.9°F (29.4°C). The month with the warmest seawater in Guánica is September, with an average ocean temperature of 84.9°F (29.4°C).
• Vega Alta - September »
  In September, in Vega Alta the rain falls for 20.4 days. In Vega Alta the average sunshine duration in September is 9.4h.
• Luquillo - September »
  In Luquillo in September, during 19.6 rainfall days, 1.77" (45mm) of precipitation is typically accumulated. In Luquillo the average relative humidity in September is 78%.
• Rincon - September »
  The month with the most rainfall in Rincon is September, when the rain falls for 21.4 days and typically aggregates up to 3.9" (99mm) of precipitation. The month with the warmest seawater in Rincon is September, with an average ocean temperature of 84.9°F (29.4°C).