Clima en San Juan (Puerto Rico) en septiembre
San Juan en septiembre: sofocante, lluvioso, con aire limpio — una apuesta, con tardes de 38°C.
Actualizado: septiembre de 2026 · normales climáticas del reanálisis ERA5
n.º 12 de 12 meses en San Juan · n.º 1120 de 1413 destinos para visitar en septiembre · confort 61/100 (nivel C)
- Días
- 32°C
- Noches
- 26°C
- Días de lluvia
- 13
- Sol
- 10.5 h
- Humedad
- 83%
- Horas de luz
- 12 h

Notas de viajeros sobre San Juan en septiembre
Notas de Charlotte Amalie, a 125 km
San Juan aún no tiene notas propias sobre septiembre; estas son de Charlotte Amalie, lo bastante cerca para compartir la temporada.
Forum posters describe September as feeling a bit hotter than other months mainly because the trade winds die down, though air and water temperatures otherwise stay fairly consistent year-round - ocean water in September is described as about as warm as it gets, a real plus for anyone prioritizing swimming. Posters characterize rain here as showers here and there rather than a genuine concern, with a full day of rain called rare even during this wetter stretch. September sits at the height of hurricane season, and while posters note no major direct hit since 1995, travel insurance is still commonly recommended given the real (if historically low) risk. The clear upside of visiting during this quieter month: fewer cruise ships, lighter crowds and easier movement around Charlotte Amalie generally.
Otros meses en San Juan
Regulars are specific this technically counts as the wettest month of the year here, edging out August, though outside of hurricane season a shower typically clears within minutes rather than settling in for the day. Our row backs that hot, genuinely showery read, 31.4C reading as a hot 36C, over 24.3C nights, with 82.7mm of rain across 5.6 days and humidity at 78 percent. Regulars are consistent the dying trade-wind breezes this time of year can make the heat feel a touch more intense than earlier spring months despite similar temperatures. This remains a genuinely good month overall, brief widely scattered showers rather than an all-day soak the standard experience. The sea sits at a warm, swimmable 28.3C. The record: 11.5 hours of sun, an 18.9 kph wind and one of the cleanest air readings in this project, AQI 30.
April is the drier end of the year here and the board frames it as the good window - out of the rainy season, humidity down, temperatures from the low seventies to the mid eighties, which is our 30.1C over 23.3C. They put the sea around 79F and our column says 26.7C, near enough the same water. The qualification our row adds is the standard one for a Caribbean dry season: 98.5mm still falls, across 6.7 days, so the showers are quick and real rather than absent. Nor is it off season - a hard winter in the States fills the island in April. The wind runs 19.1 kph off the Atlantic. The record: humidity 77 percent, 11.3 hours of sun and AQI 33.
December opens the dry season without being dry: regulars put it at about four and a half inches and warn that the month can still be wet, adding that a wet day here is not a wet day at home. Our row says 79.8mm across 11.9 days, seven millimetres apiece, under 29.6C over 23.3C. The payoff they name is specific - less rain means less runoff, so the bioluminescent bays are clearer and the glow stronger. The cost is the calendar: the festive season from about mid-December to early January is the island's high season, and air fares, hotels and car hire all climb with it. The record: humidity 82 percent, 10.1 hours of sun, a 18.8 kph wind and a 27.7C sea.
February in San Juan is mid-80s Fahrenheit, a touch cooler than the rest of the year, and the whole forum conversation is about how to read the rain figure. Our row counts 9.5 precipitation days carrying 76.3mm, and regulars explain what that looks like on the ground: fast-moving, widely scattered showers that last minutes rather than hours, often falling in one spot while the sun is out a quarter of a mile away. Their standing complaint is that the forecast sites predict rain every day of the year here, so you would never book if you believed them - one visitor got two or three hours of rain across a whole February week. The record: 29.3C days that feel like 31C, 22.3C nights, 10.7 hours of sun and a 26.1C sea.
Añade tu propia nota desde la ficha de San Juan en el mapa.
Normales climáticas de San Juan — septiembre
Medias mensuales del reanálisis ERA5. El AQI es el índice de calidad del aire de EE. UU. (US AQI) medio del mes.
Afluencia en San Juan en septiembre
Cuánta gente hay en el propio lugar: vacaciones escolares y masivas, los meses que marcó el editor y cuánto atrae su clima. Nunca cuenta en la puntuación de confort.
Tranquilovacaciones escolares en 2 de los mercados que lo llenan, uno de sus peores meses por clima(estimado)
Máxima afluenciaConcurridoTemporada mediaTranquilo
Los mejores meses para el clima de San Juan
Ordenados según la propia puntuación de confort climático de este destino a lo largo del año, algo distinto de cuánta gente hay (consulta Afluencia, más arriba).
Clima aceptableEl clima de San Juan no cambia mucho a lo largo del año: el confort se mantiene bastante estable todos los meses.
Qué hay en San Juan en septiembre
Eventos de temporada recurrentes, espectáculos naturales, cierres y festivos, seleccionados y con fuente.
- Norma
El Yunque timed reservation
1 Ene – 31 DicReserva prontoCierresThe main road into the rainforest, the one with the waterfalls and the tower, needs a timed entry reservation booked ahead. Cars without one are turned round at the gate on busy mornings. Fuente ↗
- Naturaleza
Bioluminescent bay nights
1 Ene – 31 DicBioluminiscenciaReserva prontoLaguna Grande at Fajardo glows all year, but only on the dark nights: operators sell by moon phase, and a full moon washes it out entirely. Rain in the week before also thins it.
- Riesgo
Hurricane season
1 Jun – 30 NovMaria came ashore in September 2017 and the island still plans around that month. The statistical peak is the first fortnight of September; June and November rarely deliver anything, and rates in those weeks show it. Fuente ↗
Cerca, y con algo en marcha
A menos de 300 km de San Juan —una excursión de un día o un trayecto corto— y con algo en marcha este mes. Nunca cuenta en la puntuación de confort.
¿Dónde está San Juan?
San Juan en septiembre — preguntas frecuentes
- ¿Es septiembre un buen momento para visitar San Juan?
- San Juan en septiembre: sofocante, lluvioso, con aire limpio — una apuesta, con tardes de 38°C. Es el mes n.º 12 de 12 en San Juan según la puntuación de confort de SeasonMap (61/100).
- ¿Qué tiempo hace en San Juan en septiembre?
- En septiembre, San Juan tiene una máxima media diaria de 32.4°C y una mínima de 25.9°C, con unos 146.8 mm de lluvia repartidos en unos 13.3 días de lluvia.
- ¿Cómo es la calidad del aire en San Juan en septiembre?
- En septiembre, San Juan tiene un índice de calidad del aire (US AQI) medio de unos 29.
A menos de 300 km: Turtle nesting on the east coast en Punta Cana, hacia 15 Mar – 15 Nov.