Best time to visit San Juan
Puerto Rico · Americas · Tropical climate · Northern hemisphere
January – April, December
January – April, December is the canonical best window — average daytime highs of 28 °C and 388 mm of rain across those months. The wettest month is September (181 mm) and the driest is February (64 mm).
5 months · Spring / Winter
Good · 78/100
Hot conditions with heavy annual rainfall (1380 mm); the canonical best window is January – April, December.
- Recommended window
- 5 months
- Canonical best months
- Climate zone
- Tropical
- NASA POWER normals
- Dominant season
- Winter
- Derived
- Climate score
- Good · 78/100
- Real field
- Typical stay
- 4 days
- Real field
Climate year
● recommended window · fixed scales −15–40 °C · 0–800 mm · 0–31 rain days · use ← → to change month
January
Winter · In recommended window
Favourable month (R1–R7) inside the canonical best-time window
- High / Low
- 27.3° / 23.3°C
- Mean
- 24.9°C
- Rain
- 73.1 mm
- Rain days (≥1 mm)
- 0.6
- Daylight
- 11.2 h
When to go
Go in January – April, December
January – April, December is the canonical best window — average daytime highs of 28 °C and 388 mm of rain across those months. The wettest month is September (181 mm) and the driest is February (64 mm).
Hot conditions with heavy annual rainfall (1380 mm); the canonical best window is January – April, December.
Read the full San Juan destination guide- Best
- Jan · Feb · Mar · Apr · Dec5/12
- Good
- —0/12
- Mixed
- May · Jun · Jul · Aug · Sep · Oct · Nov7/12
- Avoid
- —0/12
Distribution across the twelve months
Why these months?
San Juan's canonical best-time window is January – April, December — 5 months of the year. That window is derived from the R1–R7 classification of NASA POWER climate normals, and it is the primary signal behind the verdicts above.
Inside the window, NASA POWER climate normals for a tropical climate in the northern hemisphere read Warm / Hot with Low precipitation — 1991–2020 monthly averages, not a forecast. Outside it, month-by- month verdicts come from the R1–R7 climate classification over the same dataset.
The other 7 months sit outside the window. No month reads as least favourable on the pattern.
Signals — Best: R1–R7 favourable months · Good / Mixed: R1–R7 workable · Avoid: R1–R7 challenging · climate normals: NASA POWER 1991–2020
Read a single month
● marks a month inside the recommended window · use ← → to change month
January
Winter · In recommended window
- Temperature
- 27.3° / 23.3°C
- Precipitation
- 73.1 mm
- Rain days (≥1 mm)
- 0.6
- Daylight
- 11.2 h
Avg high 27.3°C / avg low 23.3°C · 73.1 mm precipitation over 0.6 days with ≥1 mm rain.
Temperature, precipitation and rain days are 1991–2020 NASA POWER climate normals; daylight hours are astronomical. The verdict comes from the R1–R7 climate classification.
All twelve months
Twelve months of NASA POWER climate normals for San Juan (1991–2020 average), side by side with the travel verdict: whether a month is Favourable, Workable or Challenging (R1–R7 classification), and whether it falls inside the canonical best-time window. Historical climate normals — not a forecast.
| Month | Season | Temperature | Precipitation | Month readout | Verdict |
|---|---|---|---|---|---|
| Januaryinside the recommended window; | Winter | 27.3° / 23.3°C | 73.1 mm · 0.6 rain days | Avg high 27.3°C / avg low 23.3°C · 73.1 mm precipitation over 0.6 days with ≥1 mm rain. | Best |
| Februaryinside the recommended window; | Winter | 27.6° / 23.1°C | 64.0 mm · 0.6 rain days | Avg high 27.6°C / avg low 23.1°C · 64.0 mm precipitation over 0.6 days with ≥1 mm rain. | Best |
| Marchinside the recommended window; | Spring | 28.1° / 23.2°C | 78.7 mm · 0.6 rain days | Avg high 28.1°C / avg low 23.2°C · 78.7 mm precipitation over 0.6 days with ≥1 mm rain. | Best |
| Aprilinside the recommended window; | Spring | 28.9° / 24.0°C | 88.2 mm · 0.6 rain days | Avg high 28.9°C / avg low 24.0°C · 88.2 mm precipitation over 0.6 days with ≥1 mm rain. | Best |
| May | Spring | 29.3° / 25.0°C | 140.9 mm · 0.8 rain days | Avg high 29.3°C / avg low 25.0°C · 140.9 mm precipitation over 0.8 days with ≥1 mm rain. | Mixed |
| June | Summer | 29.7° / 25.8°C | 98.4 mm · 0.8 rain days | Avg high 29.7°C / avg low 25.8°C · 98.4 mm precipitation over 0.8 days with ≥1 mm rain. | Mixed |
| July | Summer | 29.9° / 26.1°C | 114.2 mm · 0.8 rain days | Avg high 29.9°C / avg low 26.1°C · 114.2 mm precipitation over 0.8 days with ≥1 mm rain. | Mixed |
| August | Summer | 30.1° / 26.4°C | 139.3 mm · 0.9 rain days | Avg high 30.1°C / avg low 26.4°C · 139.3 mm precipitation over 0.9 days with ≥1 mm rain. | Mixed |
| September | Autumn | 29.9° / 26.4°C | 180.6 mm · 0.9 rain days | Avg high 29.9°C / avg low 26.4°C · 180.6 mm precipitation over 0.9 days with ≥1 mm rain. | Mixed |
| October | Autumn | 29.3° / 26.1°C | 163.9 mm · 0.8 rain days | Avg high 29.3°C / avg low 26.1°C · 163.9 mm precipitation over 0.8 days with ≥1 mm rain. | Mixed |
| November | Autumn | 28.2° / 25.2°C | 154.6 mm · 0.8 rain days | Avg high 28.2°C / avg low 25.2°C · 154.6 mm precipitation over 0.8 days with ≥1 mm rain. | Mixed |
| Decemberinside the recommended window; | Winter | 27.5° / 24.1°C | 83.9 mm · 0.6 rain days | Avg high 27.5°C / avg low 24.1°C · 83.9 mm precipitation over 0.6 days with ≥1 mm rain. | Best |
● marks a month inside the canonical best-time window
- Best
- Favourable month (R1–R7) inside the canonical best-time window
- Good
- Workable month (R1–R7) — a viable alternative outside the stated window
- Mixed
- Transitional month — workable with a flexible plan
- Avoid
- Challenging month (R1–R7) — least favourable climate pattern
Method: temperature and precipitation are 1991–2020 climate normals (monthly means); verdicts combine the R1–R7 climate classification with the canonical best-time window. No daily forecast, crowd level or price index is claimed.
Climate data source: NASA POWER (NASA Langley Research Center) · Climatology / Daily / Monthly point APIs · 1991–2020 · UTC+00:00 daily boundary.
Season by season
The recommended window (January – April, December) runs through Spring and Winter. Below, each season is read on two axes: the NASA POWER climate normals for San Juan's 1991–2020 record, and how much of it sits inside the canonical best-time window.
Spring
Mar · Apr · May
Hot · Low / Moderate precipitation
Avg high 28.1°C / avg low 23.2°C · 78.7 mm precipitation over 0.6 days with ≥1 mm rain.
2 of 3 months inside the recommended window
Summer
Jun · Jul · Aug
Hot · Low / Moderate precipitation
Avg high 29.7°C / avg low 25.8°C · 98.4 mm precipitation over 0.8 days with ≥1 mm rain.
Outside the recommended window
Autumn
Sep · Oct · Nov
Hot · Moderate precipitation
Avg high 29.9°C / avg low 26.4°C · 180.6 mm precipitation over 0.9 days with ≥1 mm rain.
Outside the recommended window
Winter
Jan · Feb · Dec
Warm / Hot · Low precipitation
Avg high 27.3°C / avg low 23.3°C · 73.1 mm precipitation over 0.6 days with ≥1 mm rain.
3 of 3 months inside the recommended window
Temperature and precipitation are 1991–2020 NASA POWER climate normals (qualitative buckets are derived from the monthly values); the season names follow the destination's hemisphere, and daylight hours are astronomical.
Trip shape
- Typical stay
- 4 days
- Daily budget
- 110 USD
- Currency
- USD $
- Time zone
- America/Puerto_Rico
- Airport
- SJU · San Juan
- Travel style
- Relaxed
- Region
- Americas
Frequently asked questions
What are the best months to visit San Juan?
The best months to visit San Juan are January – April, December, based on the R1–R7 classification of NASA POWER 1991–2020 climate normals. January – April, December is the canonical best window — average daytime highs of 28 °C and 388 mm of rain across those months. The wettest month is September (181 mm) and the driest is February (64 mm).
What is the weather like in San Juan?
San Juan is rated Good for climate, with a score of 78/100. Hot conditions with heavy annual rainfall (1380 mm); the canonical best window is January – April, December.
How many days do you need in San Juan?
We recommend 4 days in San Juan, ideally placed inside the recommended window of January – April, December.
Plan a January trip to San Juan
The recommended window is January – April, December. The planner opens with San Juan prefilled — set your dates inside that window and build the route around it.
Plan around this window
Climate data source: NASA POWER (NASA Langley Research Center) · Climatology / Daily / Monthly point APIs · 1991–2020 · accessed 2026-09-13 · dataset nasa-power-canonical-production-v1.2-wave2