Weather by month: climate context for the old town
The best time to visit San Juan depends partly on how much outdoor sightseeing is planned. For a useful comparison of months, the figures here come from NOAA's Luis Muñoz Marín Airport station and the normal period 1991 to 2020. The summary PDF was generated on 24 July 2025. These are long-term airport reference values, rather than readings taken inside the historic centre or a forecast for an individual trip.
Old San Juan weather planning therefore needs two stages. Use the climate pattern to choose a broad travel period, then consult the current forecast before setting out. A monthly rainfall normal describes the month's average context across the reference period. It does not tell you which afternoon will be wet or how the sky will look during a particular sunset outing.
February and March as relatively dry months
February's mean daily high and low are 28.8°C and 22.1°C, with 65.5 mm of monthly rainfall. March has 29.3°C and 22.4°C, with 55.4 mm. These are the relatively dry choices in the station's monthly comparison. They make a useful starting point for a trip centred on streets, fortifications and outdoor views, while still leaving the daily plan responsive to weather.
The same NOAA series gives November 187.2 mm of rainfall, with mean daily temperatures of 30.1°C at the high and 23.8°C at the low. January has 103.4 mm and December 123.2 mm. Choosing dates is therefore more useful when based on the actual monthly pattern than on a single label applied to the whole end of the year. Keep a flexible order for outdoor activities.
A sunset outing
Consider a bay cruise with music and refreshments when planning time outdoors.
Hand-picked tours, booked through GetYourGuide. Prices are indicative starting prices in US dollars (as of November 2026). Tap a tour for live availability and the current price in your currency.
Plan an evening on the bay
A two-hour sunset cruise includes cocktails, soft drinks, appetisers and music. Reach San Juan Bay Marina independently and choose the date with the day's weather in mind.
Monthly normals at a glance
The table uses the NOAA airport station, normal period 1991 to 2020, PDF dated 24 July 2025. Temperatures are mean daily highs and lows; rainfall is the monthly normal. Use it to compare months rather than to predict conditions at a particular street, beach or rainforest trail.
| Month | High °C | Low °C | Rain mm |
|---|---|---|---|
| January | 28.4 | 22.2 | 103.4 |
| February | 28.8 | 22.1 | 65.5 |
| March | 29.3 | 22.4 | 55.4 |
| April | 30.1 | 23.3 | 116.8 |
| May | 30.8 | 24.3 | 140.7 |
| June | 31.7 | 25.1 | 118.4 |
| July | 31.5 | 25.3 | 152.9 |
| August | 31.7 | 25.4 | 159.8 |
| September | 31.8 | 25.3 | 165.1 |
| October | 31.4 | 24.8 | 132.3 |
| November | 30.1 | 23.8 | 187.2 |
| December | 29.0 | 22.9 | 123.2 |
Hurricane season from 1 June to 30 November
The Atlantic hurricane season includes the Caribbean and runs from 1 June to 30 November. The calendar is a planning framework, with tropical storms also possible outside that period. Follow current official forecasts and travel instructions close to departure. Separate the broad seasonal choice from the operational decision about a particular walk or boat outing.
Leave room to rearrange the order of activities. If a boat trip is an important part of the stay, choose a date that leaves some flexibility elsewhere in the itinerary. Follow the outing's current arrangements when weather affects the plan, and use the boat tour comparison to distinguish an evening cruise from daytime sailing.
Walks in the heat, fort days and boat dates
Plan manageable outdoor stages, water and sun protection for old town walks. Older NPS safety guidance dated 22 January 2020 warns about strong sun and steep, uneven or slippery surfaces. Wear shoes with grip, accompany children around the defences and keep off walls and cannons. A manageable route leaves time for pauses rather than treating every stop as compulsory.
For the forts, regular hours are 09:00 to 17:00 according to the operating information updated on 27 August 2025 and checked on 11 November 2026. Listed closures are 26 November 2026, 25 December 2026 and 1 January 2027. Keep these scheduled interior visits distinct from exterior views.
The featured sunset cruise lasts two hours and starts at San Juan Bay Marina. Cocktails, soft drinks, appetisers and music are included; transportation is extra. The outing stays on the water, with no swimming or shore stop. Put the journey to the marina into the plan separately from time spent exploring the old town.
On the day, choose outdoor stages that suit both the conditions and the party. A shorter route with time to look around can be more rewarding than several tightly packed visits. Keep the meeting time for a guided outing as the reference point, and arrange the freely planned parts of the day around it.
Questions about timing a visit
Which months are relatively dry?
February and March have relatively low rainfall in the airport's 1991 to 2020 normals. Use that comparison alongside a current forecast for your actual dates.
Do the figures describe the old town itself?
They come from Luis Muñoz Marín Airport. They provide a coastal climate reference, with monthly mean daily temperatures and rainfall normals.
Can a sunset cruise replace a fort visit?
They offer different experiences. The cruise is an evening on the bay with drinks, snacks and music; fort interiors need their own opening-hour plan.