January in San Juan — one of the year's strongest windows (2nd)
Best window · 8.9/10January averages 26°C (78°F) — warm enough for beach and boat plans, still short of the heat that pushes sightseeing into early morning.
Expect 44 mm of rain — occasional showers rather than washed-out days — alongside about 18 days with 6+ hours of sunshine and 11 daylight hours.
A 8.9/10 puts this among the year's best months in San Juan (2nd of 12); only March scores higher, at 9.4/10.
Figure on peak pricing, with crowds are moderate. You are paying the year's highest rates for the year's best conditions — book early or shift a few weeks either side.
Pack light clothing, swimwear and real sun protection.
February ranks 3rd of 12 for San Juan — one of the best windows
Best window · 8.7/10February averages 25°C (78°F) — warm enough for beach and boat plans, still short of the heat that pushes sightseeing into early morning.
Rainfall runs 59 mm, so plan one flexible day in three; you still get about 19 days with 6+ hours of sunshine and 11.4 hours of daylight.
A 8.7/10 puts this among the year's best months in San Juan (3rd of 12); only March scores higher, at 9.4/10.
Figure on mid-season pricing, with crowds are moderate.
Pack light clothing, swimwear and real sun protection, a packable rain layer.
March: the best month of the year in San Juan
Best window · 9.4/10Days in March average 26°C (79°F) and humidity near 73% — front-load outdoor plans before the heat builds and treat the middle of the day as indoor time.
Budget for roughly 47 mm of rain this month — a flexible day or two helps — with about 28 days with 6+ hours of sunshine and 11.9 hours of daylight to work around it.
On our climate-comfort scale this is the top-ranked month of the year for San Juan at 9.4/10 — the reference point every other month on this page is measured against.
Expect peak pricing, and this is one of the busiest months here. You are paying the year's highest rates for the year's best conditions — book early or shift a few weeks either side.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a packable rain layer.
April ranks 5th of 12 for San Juan — one of the best windows
Best window · 8.6/10April averages 27°C (80°F) and humidity near 75%, so the practical pattern is early mornings, a long midday break, and evenings back outside.
Rainfall runs 95 mm, so plan one flexible day in three; you still get about 28 days with 6+ hours of sunshine and 12.4 hours of daylight.
A 8.6/10 puts this among the year's best months in San Juan (5th of 12); only March scores higher, at 9.4/10.
Plan for mid-season pricing, with crowds are moderate.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a packable rain layer.
May in San Juan: strong conditions, 7th of 12
Good · 7.9/10Days in May average 28°C (82°F) and humidity near 78% — front-load outdoor plans before the heat builds and treat the middle of the day as indoor time.
140 mm of rain makes this a wet month here, though with about 28 days with 6+ hours of sunshine there is still bright weather between the fronts.
That is 7.9/10 on the same scale — 7th of 12 months, versus 9.4/10 for the best month here.
Budget for mid-season pricing, and crowds are moderate.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a proper rain shell rather than an umbrella.
If your dates are flexible, March is materially better in San Juan — 1.5 points higher on the same scale.
June ranks 4th of 12 for San Juan — one of the best windows
Best window · 8.7/10June averages 29°C (84°F) and humidity near 78%, so the practical pattern is early mornings, a long midday break, and evenings back outside.
Rainfall runs 88 mm, so plan one flexible day in three; you still get about 29 days with 6+ hours of sunshine and 13.1 hours of daylight.
A 8.7/10 puts this among the year's best months in San Juan (4th of 12); only March scores higher, at 9.4/10.
Plan for mid-season pricing, with crowds are moderate.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a packable rain layer.
July holds up well in San Juan — 6th best month
Good · 8.2/10July averages 29°C (83°F) and humidity near 80%, so the practical pattern is early mornings, a long midday break, and evenings back outside.
Monthly rainfall reaches 118 mm — wet for this destination — but about 27 days with 6+ hours of sunshine still break through, so keep one indoor fallback in the plan.
It scores 8.2/10 here, 6th of 12 months, against 9.4/10 in the destination's best month.
Figure on mid-season pricing, with crowds are moderate.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a proper rain shell rather than an umbrella.
August in San Juan — reliably good (8th best month)
Good · 7.8/10Days in August average 29°C (84°F) and humidity near 80% — front-load outdoor plans before the heat builds and treat the middle of the day as indoor time.
147 mm of rain makes this a wet month here, though with about 28 days with 6+ hours of sunshine there is still bright weather between the fronts.
That is 7.8/10 on the same scale — 8th of 12 months, versus 9.4/10 for the best month here.
Budget for mid-season pricing, and crowds are moderate.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a proper rain shell rather than an umbrella.
If your dates are flexible, March is materially better in San Juan — 1.6 points higher on the same scale.
September in San Juan: strong conditions, 9th of 12
Good · 7.7/10Days in September average 29°C (84°F) and humidity near 79% — front-load outdoor plans before the heat builds and treat the middle of the day as indoor time.
151 mm of rain makes this a wet month here, though with about 26 days with 6+ hours of sunshine there is still bright weather between the fronts.
That is 7.7/10 on the same scale — 9th of 12 months, versus 9.4/10 for the best month here.
Expect mid-season pricing, and crowds are light for this destination.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a proper rain shell rather than an umbrella.
If your dates are flexible, March is materially better in San Juan — 1.7 points higher on the same scale.
October in San Juan — reliably good (11th best month)
Good · 7.2/10October averages 29°C (83°F) and humidity near 79%, so the practical pattern is early mornings, a long midday break, and evenings back outside.
218 mm makes this the wettest stretch of the year, though about 21 days with 6+ hours of sunshine still appear — keep an indoor fallback ready.
It scores 7.2/10 here, 11th of 12 months, against 9.4/10 in the destination's best month.
Plan for low-season pricing, with crowds are light for this destination.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a proper rain shell rather than an umbrella.
Flexible dates? March scores 2.2 points higher here — enough to change the trip.
November in San Juan — workable with trade-offs
Trade-offs · 6.4/10November averages 27°C (81°F) and humidity near 82%, so the practical pattern is early mornings, a long midday break, and evenings back outside.
203 mm of rain puts this in monsoon territory — about 15 days with 6+ hours of sunshine across the whole month, and multi-day washouts are normal.
It scores 6.4/10 here, 12th of 12 months, against 9.4/10 in the destination's best month.
Figure on low-season pricing, with crowds are light for this destination.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a proper rain shell rather than an umbrella.
Flexible dates? March scores 3 points higher here — enough to change the trip.
December in San Juan — reliably good (10th best month)
Good · 7.7/10Days in December average 26°C (79°F) and humidity near 79% — front-load outdoor plans before the heat builds and treat the middle of the day as indoor time.
Budget for roughly 77 mm of rain this month — a flexible day or two helps — with about 15 days with 6+ hours of sunshine and 10.9 hours of daylight to work around it.
That is 7.7/10 on the same scale — 10th of 12 months, versus 9.4/10 for the best month here.
Expect mid-season pricing, and crowds are moderate.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a packable rain layer.
If your dates are flexible, March is materially better in San Juan — 1.7 points higher on the same scale.
