Guaynabo Weather Forecast

    • 77
    • 88

    Rain Showers

    • 76
    • 90

    Rain Showers

    • 76
    • 90

    Rain Showers

    • 77
    • 89

    Rain Showers

    • 77
    • 91

    Rain Showers

    • 77
    • 91

    Rain Showers

Today 18 Sep San Juan and Vicinity

Mostly cloudy with isolated Thunderstorms. Scattered Showers late this Morning, then numerous Showers this afternoon. Highs around 91. Temperature falling this afternoon. Southeast Winds 10 to 15 Mph. Chance of rain 70 percent.

Tonight 18 Sep San Juan and Vicinity

Variably cloudy with scattered Showers with isolated Thunderstorms. Lows around 83. Southeast Winds 5 to 10 Mph. Chance of rain 50 percent.

Graph Plots Open in Graphs

  • Temperature Forecast NOAA

  • Temperature Real-Time

Guaynabo Temperature Statistics

September Temperature

San Juan Fernando Luis Ribas Dominicci (6.8 miles)

  • Lowest 7 September, 2025

    78.8 °F

  • Average September

    85.2 °F

  • Highest 3 September, 2025

    89.6 °F

Climate (2020–Present)

San Juan Fernando Luis Ribas Dominicci (6.8 miles)

Take a look at our website widgetsAvailable free! Find Out More

  • Average Low 2020–2025

    77.7 °F

  • Average 2020–2025

    82.4 °F

  • Average High 2020–2025

    85.1 °F
Get WillyWeather+ to remove ads