Best time to visit Istanbul

Re-score for me — drag the dial — every chart on the page recolours live for your heat limit 27°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.

Saved to this browser. Changes update the strips below.
Recent · 2020-2024
Interest Google Trends 2021-2025 searches, not arrivals (?)
Day · avg daily high (?)
Night · avg overnight low (?)
Heatwaves · days/yr ≥35°C ETCCDI TX35 (?)
<11
Tropical nights · nights/yr ≥20°C ETCCDI TR20 — sleep killer (?)
522248
UV index · On a typical day around midday, UV is about this (?)
123568875321
On the sunniest 1 in 10 days, UV reaches this — and even higher
467996
PM2.5 air quality · on a typical day (?)
332931221915141315182330
On the worst 1 in 10 days, PM2.5 reaches this — and even higher
614952382826212025323958
September 9/10 feels 25°C (+1°C vs 1991-2020) · HCI 92/100
Day 26° · Night 18° · cools 8° at night 🌙 8 tropical nights/yr · peak 14 56% humidity 22 km/h wind 7 rain days (77h) 248h sun
Thermal 9
Sky 10
Rain 8
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 Istanbul

30 top-rated tours via Viator. Booking links earn this site a commission at no cost to you.

  1. 1Istanbul to Gallipoli Full Day Tour with Lunch and Transfers4.87★ (603)17hfrom $154🔥 Selling fast
  2. 2Two Markets, Two Continents with Culinary Backstreets4.98★ (535)6h 30mfrom $145🔥 Selling fast
  3. 3Istanbul Traditional Turkish Dinner and Dervish Experience4.94★ (578)from $101
  4. 4ISTANBUL Full-Day PRIVATE Guided Tour; For the Top Historic Sites4.96★ (268)from $79🔥 Selling fast
  5. 5Best of Istanbul 1, 2 or 3-Day Private Guided Istanbul Tour4.96★ (9,411)from $100
  6. 6ISTANBUL BEST: Iconic Landmarks Full Day PRIVATE Guided City Tour4.95★ (1,233)from $80
  7. 7Istanbul Private Transfer - IST Airport, Cruise Ports and Hotels4.82★ (1,018)from $65
  8. 8Istanbul Blue Mosque, Hagia Sophia, Basilica Cistern with Tickets4.93★ (58)3hfrom $135🔥 Selling fast
  9. 9Istanbul Highlights Private Tour with skip line ticket options4.80★ (676)from $69
  10. 10Half Day Private Istanbul Tour4.92★ (158)4hfrom $261
  11. 11Istanbul Taste of Two Continents Food Tour - Spice Market & Ferry4.96★ (3,406)5h 30mfrom $135
  12. 12Istanbul Bosphorus Sunset Luxury Yacht Cruise with Snacks4.88★ (2,248)2h 30mfrom $59
  13. 13Istanbul Gedikpasa Historical Turkish Bath with Privacy Option4.94★ (1,524)1hfrom $59
  14. 14Bosphorus Yacht Cruise with Stopover on the Asian Side - (Morning or Afternoon)4.91★ (1,738)2h 30mfrom $47
  15. 15Turkish Food Night and Rooftop Experience Istanbul4.94★ (829)3h 15mfrom $79
  16. 16Luxury Bosphorus Yacht Tour – Asian Side Stop & Exploration4.96★ (862)2h 30mfrom $36
  17. 17Bosphorus Evening Cruise: Dinner, Live Shows & Private Table4.90★ (1,021)3hfrom $32
  18. 18Bosphorus Yacht Cruise with Live Guide & Asian Side Stop4.97★ (2,316)2h 30mfrom $71
  19. 19Enjoy Istanbul’s Bosphorus:2-Hour Daytime, Sunset & Night Cruises4.95★ (1,748)2hfrom $12
  20. 20Istanbul Highlights: Small-Group Tour with a Local Expert4.98★ (525)from $49
  21. 21Istanbul E-pass: Top Istanbul Attractions with Skip The Ticket Line4.81★ (1,464)from $196
  22. 22Istanbul Sunset Cruise Experience on Luxury Yacht -Local guide4.94★ (2,102)2hfrom $30
  23. 23Sunset or Daytime Istanbul Luxury Yacht Cruise with Snacks4.86★ (1,990)2hfrom $36
  24. 24Istanbul Bosphorus Sunset Cruise Experience on Luxury Yacht4.94★ (4,933)2h 15mfrom $53
  25. 25Istanbul Two Continents Tour By Bus And Bosphorus Cruise4.84★ (570)10hfrom $107
  26. 26Istanbul Bosphorus Dinner Cruise: Live Folk Dance & DJ Experience4.50★ (1,447)3hfrom $27
  27. 27Istanbul Princess Island Tour Include Lunch and Island Car Trip4.92★ (465)9hfrom $37
  28. 282 Day All Inclusive Cappadocia Tour from Istanbul with Optional Balloon Flight4.94★ (448)48hfrom $747
  29. 29Taste of Istanbul: Local Food and Culture Tour4.99★ (107)from $36
  30. 30Private Basilica Cistern Skip-the Line Ticket Entry4.83★ (6)45mfrom $85

Last refreshed 2026-05-25.

Similar climatesLyon88% · Siena87% · Bordeaux87%

Other destinations with the most-alike year-round climate to Istanbul (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 Istanbul'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 4–10 6 12 149 12.4 72% 24 130 1 Quiet 5
Feb 4–11 7 10 128 12.8 70% 23 150 2 Quiet 5
Mar 5–12 8 13 169 13.0 70% 22 168 3 Quiet 5
Apr 9–17 14 10 120 12.0 65% 22 211 5 Quiet 7
May 12–21 20 9 96 10.7 62% 21 267 6 Quiet 8
Jun 18–26 26 9 92 10.2 61% 21 290 8 Quiet 9
Jul 21–29 30 4 52 13.0 53% 24 314 8 Quiet 8
Aug 21–30 31 4 42 10.5 54% 24 293 7 Peak 7
Sep 18–26 25 7 77 11.0 56% 22 248 5 Busy 9
Oct 14–21 20 6 80 13.3 64% 21 201 3 Moderate 9
Nov 10–16 14 9 94 10.4 68% 23 157 2 Peak 7
Dec 7–13 10 12 149 12.4 75% 21 127 1 Moderate 5

UV Index in Istanbul by Month

UV index in Istanbul peaks at 8 (very high) in July, dropping to 1 (low) in January. July 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

September

9/10

18–26°C · 7 rain days (77h) · 248 sun hours · 56% humidity · Busy crowd · UV 5 (moderate) · sunniest 1 in 10 days reach 6 (high)

October

9/10

14–21°C (feels 20°C) · 6 rain days (80h) · 201 sun hours · 64% humidity · Moderate crowd · UV 3 (moderate)

June

9/10

18–26°C · 9 rain days (92h) · 290 sun hours · 61% humidity · Quiet crowd · UV 8 (high) · sunniest 1 in 10 days reach 9 (very high)

Every month

Show the other 9 months in detail

January

5/10

4–10°C (feels 6°C) · 12 rain days (149h) · 130 sun hours · 72% humidity · Quiet crowd · UV 1 (low)

February

5/10

4–11°C (feels 7°C) · 10 rain days (128h) · 150 sun hours · 70% humidity · Quiet crowd · UV 2 (low)

March

5/10

5–12°C (feels 8°C) · 13 rain days (169h) · 168 sun hours · 70% humidity · Quiet crowd · UV 3 (low) · sunniest 1 in 10 days reach 4 (moderate)

April

7/10

9–17°C (feels 14°C) · 10 rain days (120h) · 211 sun hours · 65% humidity · Quiet crowd · UV 5 (moderate) · sunniest 1 in 10 days reach 6 (high)

May

8/10

12–21°C (feels 20°C) · 9 rain days (96h) · 267 sun hours · 62% humidity · Quiet crowd · UV 6 (moderate) · sunniest 1 in 10 days reach 7 (high)

July

8/10

21–29°C · 4 rain days (52h) · 314 sun hours · 53% humidity · Quiet crowd · UV 8 (very high)

August

7/10

21–30°C · 4 rain days (42h) · 293 sun hours · 54% humidity · Peak crowd · UV 7 (high) · sunniest 1 in 10 days reach 9 (very high)

November

7/10

10–16°C (feels 14°C) · 9 rain days (94h) · 157 sun hours · 68% humidity · Peak crowd · UV 2 (low)

December

5/10

7–13°C (feels 10°C) · 12 rain days (149h) · 127 sun hours · 75% humidity · Moderate crowd · UV 1 (low)

Frequently asked questions about visiting Istanbul

When is the best time to visit Istanbul?

September is the highest-scoring month (9/10 on the Holiday Climate Index). Typical conditions: 18–26°C (7 rainy days). The top three months by score are September, October, June.

What is the worst time to visit Istanbul?

January is the lowest-scoring month (5/10). Typical conditions: 4–10°C (12 rainy days).

Is Istanbul too hot in summer?

2 months (July, August) 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 Istanbul?

Search-interest seasonality (Google Trends 2021-2025) is lowest in January and peaks in August. 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.

Which months in Istanbul have good weather but fewer tourists?

June (climate 9/10, crowd index 4) and October (climate 9/10, crowd index 47) — shoulder months with above-average climate and below-median search-interest. Often the best value-for-weather trade.

What is the UV index in Istanbul by month?

UV peaks at 8 (very high) in July and is lowest in January at 1 (low). Monthly peak values: Jan 1, Feb 2, Mar 3, Apr 5, May 6, Jun 8, Jul 8, Aug 7, Sep 5, Oct 3, Nov 2, Dec 1. July 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 Istanbul in July?

July is the peak UV month in Istanbul, with a daily-peak UV index of 8 (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 Istanbul 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. June is the worst case: typical days average UV 8 (high), but the top 10% of days reach UV 9 (very high) — and even higher. Months where the sunniest days routinely exceed the typical reading: March, April, May, June, August, September. Plan sun protection for the worst case, not the average.

Is air quality in Istanbul bad for travelers?

PM2.5 (fine-particle pollution) exceeds the WHO sensitive-group guideline (15 µg/m³) in 12 months: January, February, March, April, May, June, July, August, September, October, November, December. The worst month is January with a typical-day mean of 33 µg/m³ (unhealthy); on the worst 10% of days PM2.5 reaches 61 µg/m³ (hazardous) 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.