Best time to visit San Juan

Re-score for me — drag the dial — every chart recolours live for your heat & sea limits 27°C · sea 29°C
I'm comfortable up to 27°C feels-like
22° heat-averse 30° heat-loving

Default 27 °C is the upper edge of the Holiday Climate Index "ideal comfort" band (Scott, Rutty, Amelung & Tang, 2016). Above this, most warm-tourism travellers report measurable discomfort.

Sea feels bathtub at 29°C
26° strict 31° tolerant

Default 29 °C is the Beach Climate Index "bathtub" line (Morgan et al.) — where the sea stops being refreshing and starts feeling like a warm bath.

Saved to this browser. Changes update the strips below.
Sea temp cold <18° chilly 18–21° ideal 22–26° warm 27–28° bathtub 29–30° too warm ≥31°
Recent · 2020-2024
Interest Google Trends 2021-2025 searches, not arrivals (?)
Sea Nov 2022 – Dec 2024 (?)
Day · avg daily high (?)
Night · avg overnight low (?)
UV index · On a typical day around midday, UV is about this (?)
7810101099109876
On the sunniest 1 in 10 days, UV reaches this — and even higher
91111111111107
PM2.5 air quality · on a typical day (?)
57666101186656
On the worst 1 in 10 days, PM2.5 reaches this — and even higher
8109910182014101298
February 5/10 feels 29°C (−1°C vs 1991-2020) · HCI 50/100
Day 28° · Night 22° 63% humidity 24 km/h wind 17 rain days (215h) 229h sun sea 27°C
Thermal 7
Sky 4
Rain 3
Wind 9

Higher = better, including rain & wind (green = "doesn't hurt the score", not "lots of it").

Compare with another destination

Add as many as you like — stacked below the main strips above. Each row is just the recent-window score strip and (for beach destinations) sea-temperature strip.

Tours in San Juan

28 top-rated tours via Viator. Booking links earn this site a commission at no cost to you. Map locations are approximate (centred on San Juan).

  1. 1Two-in-One Day Trip: El Yunque and Bio Bay Tour with Transport4.87★ (1,399)12hfrom $184🔥 Selling fast
  2. 2San Juan Catamaran Sunset Sail with Drinks Included4.93★ (667)2hfrom $119🔥 Selling fast
  3. 3Night Kayak - Condado City Lights Tour4.73★ (4,853)1hfrom $69🔥 Selling fast
  4. 4Rainforest Cave Tubing & Waterfalls Hiking Adventure4.95★ (222)4hfrom $79🔥 Selling fast
  5. 5Puerto Rico: Bio Bay Swim and Sunset Charter or Late night tour4.89★ (338)2hfrom $65🔥 Selling fast
  6. 6Top Rated El Yunque Rainforest & Waterslide – SmallGroup Tour4.90★ (15,675)7hfrom $45
  7. 7Mixology Class at Casa BACARDÍ in Puerto Rico4.83★ (1,717)1h 15mfrom $89
  8. 8San Juan Guided Turtle Snorkel Tour and Complimentary Videos4.89★ (16,872)1h 30mfrom $42
  9. 9Cave, Waterfall and River Adventure in Charco Azul from San Juan4.95★ (2,304)5hfrom $115
  10. 10Jet Ski Tour through San Juan Bay4.80★ (675)1h 20mfrom $169
  11. 11Clear Kayak Tour in Condado Lagoon4.87★ (1,551)1hfrom $65
  12. 12Authentic Flavors of San Juan Food Tour4.90★ (5,133)3hfrom $170
  13. 13Small Group El Yunque Half Day Tour with Transport: Waterslide4.91★ (1,021)from $89
  14. 14Small-Group El Yunque Waterslide & transportation w/ Photos4.90★ (3,639)6hfrom $44
  15. 15El Yunque Tour with Luquillo Lunch Stop and Transport: 6 ppl Max4.94★ (2,314)from $95
  16. 16Puerto Rico Jet Snorkel with Turtles and Videos in San Juan4.94★ (2,346)1h 30mfrom $99
  17. 17Full-Day Cueva Ventana, Indian Cave and Waterfall Adventure4.90★ (688)from $155
  18. 18El Yunque Exclusive Experience: Waterslide Adventures w/Transport4.83★ (757)6h 30mfrom $59
  19. 19Savor the Sunset: Old San Juan Walking Food Tour4.90★ (659)3hfrom $179
  20. 20Beginner Scuba Diving with Turtles and Free Videos, San Juan4.89★ (2,252)1h 30mfrom $99
  21. 21San Juan Bay Day Sail with Drinks Included4.88★ (559)1h 30mfrom $99
  22. 22Old San Juan Walking Tour4.82★ (2,490)2h 15mfrom $39
  23. 23Old San Juan and El Morro Castle Walking Tour4.86★ (687)2h 30mfrom $54
  24. 24Full-Day Zipline and Waterfall Rappelling Adventure Near San Juan4.97★ (940)from $165
  25. 25Arenales River Caving, Waterfall &Tropical Forest Secret Spring4.98★ (1,738)from $125
  26. 26Historic Old San Juan Sunset Walking Tour4.81★ (708)2hfrom $39
  27. 27Let me show you MY Island Tour With visit to El Yunque4.88★ (1,616)from $89
  28. 28El Yunque Rainforest and Luquillo Kiosk Day Trip5.00★ (521)from $85

Last refreshed 2026-06-30.

Similar climatesHoletown90% · Punta Cana89% · Bridgetown86%

Other destinations with the most-alike year-round climate to San Juan (apparent temperature, rain hours, sunshine — matched within the same trip-profile). The ±N chip compares each match's typical score for the current month against San Juan's. Based on the 2020-2024 climatology, not this year's actual weather.

Month-by-month

Month Temp °C Feels °C Rain days Rain h Rain h/day Humidity Wind km/h Sun h UV Interest Score
Jan 22–28 29 15 213 14.2 64% 23 249 7 Quiet 5
Feb 22–28 29 17 215 12.6 63% 24 229 8 Quiet 5
Mar 22–28 29 17 223 13.1 60% 24 260 10 Quiet 5
Apr 23–29 31 18 221 12.3 60% 23 264 10 Quiet 4
May 24–31 34 18 176 9.8 59% 22 278 10 Quiet 3
Jun 25–32 34 19 183 9.6 60% 24 272 9 Quiet 3
Jul 25–31 33 21 242 11.5 67% 27 275 9 Quiet 2
Aug 26–31 34 19 222 11.7 68% 25 266 10 Busy 3
Sep 25–31 35 22 230 10.5 70% 21 246 9 Moderate 2
Oct 25–31 34 20 212 10.6 69% 19 242 8 Quiet 3
Nov 24–29 32 18 222 12.3 69% 21 221 7 Peak 3
Dec 23–28 30 17 233 13.7 66% 22 245 6 Peak 4

UV Index in San Juan by Month

UV index in San Juan peaks at 10 (very high) in May, dropping to 6 (moderate) in December. March, April, May, June, July, August, September, October reach very high or extreme levels — apply SPF 50+, wear a hat and protective clothing, and limit direct sun between 11:00 and 17:00.

Best months in detail

February

5/10

22–28°C · 17 rain days (215h) · 229 sun hours · 63% humidity · Quiet crowd · UV 8 (high) · sunniest 1 in 10 days reach 9 (very high)

January

5/10

22–28°C (feels 29°C) · 15 rain days (213h) · 249 sun hours · 64% humidity · Quiet crowd · UV 7 (high)

March

5/10

22–28°C · 17 rain days (223h) · 260 sun hours · 60% humidity · Quiet crowd · UV 10 (very high)

Every month

Show the other 9 months in detail

April

4/10

23–29°C (feels 31°C) · 18 rain days (221h) · 264 sun hours · 60% humidity · Quiet crowd · UV 10 (very high) · sunniest 1 in 10 days reach 11 (extreme)

May

3/10

24–31°C (feels 34°C) · 18 rain days (176h) · 278 sun hours · 59% humidity · Quiet crowd · UV 10 (very high) · sunniest 1 in 10 days reach 11 (extreme)

June

3/10

25–32°C (feels 34°C) · 19 rain days (183h) · 272 sun hours · 60% humidity · Quiet crowd · UV 9 (very high)

July

2/10

25–31°C (feels 33°C) · 21 rain days (242h) · 275 sun hours · 67% humidity · Quiet crowd · UV 9 (very high) · sunniest 1 in 10 days reach 11 (very high)

August

3/10

26–31°C (feels 34°C) · 19 rain days (222h) · 266 sun hours · 68% humidity · Busy crowd · UV 10 (very high) · sunniest 1 in 10 days reach 11 (extreme)

September

2/10

25–31°C (feels 35°C) · 22 rain days (230h) · 246 sun hours · 70% humidity · Moderate crowd · UV 9 (very high) · sunniest 1 in 10 days reach 11 (very high)

October

3/10

25–31°C (feels 34°C) · 20 rain days (212h) · 242 sun hours · 69% humidity · Quiet crowd · UV 8 (very high) · sunniest 1 in 10 days reach 10 (very high)

November

3/10

24–29°C (feels 32°C) · 18 rain days (222h) · 221 sun hours · 69% humidity · Peak crowd · UV 7 (high)

December

4/10

23–28°C (feels 30°C) · 17 rain days (233h) · 245 sun hours · 66% humidity · Peak crowd · UV 6 (moderate) · sunniest 1 in 10 days reach 7 (high)

Frequently asked questions about visiting San Juan

When is the best time to visit San Juan?

February is the highest-scoring month (5/10 on the Holiday Climate Index). Typical conditions: 22–28°C (17 rainy days). The top three months by score are February, January, March.

What is the worst time to visit San Juan?

September is the lowest-scoring month (2/10, capped by extreme heat). Typical conditions: 25–31°C (22 rainy days).

Is San Juan too hot in summer?

9 months (April, May, June, July, August, September, October, November, December) trip the heat deal-breaker in our scoring: apparent temperature crosses the comfort cap, so even with clear skies and low rain the score is held down. Plan around it if heat tolerance is low.

When are crowds lowest in San Juan?

Search-interest seasonality (Google Trends 2021-2025) is lowest in May and peaks in November. Interest tracks both in-trip visitors and lead-time planners, so treat it as a "destination is on people's minds" signal rather than literal arrivals.

What is the UV index in San Juan by month?

UV peaks at 10 (very high) in May and is lowest in December at 6 (moderate). Monthly peak values: Jan 7, Feb 8, Mar 10, Apr 10, May 10, Jun 9, Jul 9, Aug 10, Sep 9, Oct 8, Nov 7, Dec 6. March, April, May, June, July, August, September, October reach very high or extreme levels — apply SPF 50+, wear a hat and protective clothing, and limit direct sun between 11:00 and 17:00.

What is the UV index in San Juan in May?

May is the peak UV month in San Juan, with a daily-peak UV index of 10 (very high). At this level, sunburn can occur in under 20 minutes on unprotected fair skin. Apply SPF 50+, wear protective clothing and a hat, and avoid direct midday sun (11:00–17:00).

How high can UV get in San Juan on the sunniest days?

Most days look like the monthly average, but on the sunniest ~1 in 10 days UV climbs higher than the mean suggests. April is the worst case: typical days average UV 10 (very high), but the top 10% of days reach UV 11 (extreme) — and even higher. Months where the sunniest days routinely exceed the typical reading: February, April, May, July, August, September, October, December. Plan sun protection for the worst case, not the average.

Is air quality in San Juan bad for travelers?

PM2.5 (fine-particle pollution) exceeds the WHO sensitive-group guideline (15 µg/m³) in 2 months: June, July. The worst month is July with a typical-day mean of 11 µg/m³ (moderate); on the worst 10% of days PM2.5 reaches 20 µg/m³ (unhealthy for sensitive) and higher. People with asthma, heart conditions, or sensitive children may want to avoid these months or limit outdoor activity. Source: CAMS via Open-Meteo.