Avg High
Istanbul in May
Avg Low
Rain
Daylight
14h
What to expect
May in Istanbul is late spring, a shoulder-season window, so you can get a bit of variety across the month. The month is mostly mild for steady exploring, with a noticeable cool-down after sunset. There is plenty of daylight to stretch outdoor time. Most days feel close to what the averages suggest, with straightforward pacing.
May in context
How it compares to the rest of the year in Istanbul.
Hottest (avg)
#5 / 12
Wettest (avg)
#9 / 12
Daylight Hours
#3 / 12
Windiest (avg)
#12 / 12
Highest UV
#3 / 12
Most Humid
#7 / 12
Monthly climate breakdown
Temperature
- Daytime high
-
- Nighttime low
-
- Feels like (avg)
-
Sunshine
- Daylight hours
- 14.5 h
- UV index (max)
- 7
- Typical sun hours
- 05:46 - 20:15
Rain & Snow
- Total rain
-
- Rainy days
- 8 days
- Cloud cover (avg)
- 45%
Humidity & Wind
- Humidity (avg)
- 76%
- Wind (avg)
-
- Wind (max gusts)
-
Daily climate explorer
Day 15 selected for May. Typical high 20.0°C and low 13.6°C.
Typical disruptions in May
Based on 30 years of historical data, these are the disruption patterns most likely to affect plans in May.
Rain High impact
Washout risk Measures: Washout day risk. Observed about 8% of days (2.4 days/month) in May. Historical risk signal only, not a day-by-day forecast.
2.4 days / month
~8% of days
Why this matters
- Expected days 2.4 days / month
- Probability ~8% of days
- Intensity Up to ~20mm (P95)
Washout conditions are possible on ~2 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Rain Moderate
Rain disruption Measures: Likely rain disruption days. Observed about 8% of days (2.6 days/month) in May. Historical risk signal only, not a day-by-day forecast.
2.6 days / month
~8% of days
Why this matters
- Expected days 2.6 days / month
- Probability ~8% of days
- Intensity Up to ~19mm (P95)
Rain disruption risk appears on ~3 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Show all disruptions (15 more)
Rain High impact
Washout run Measures: Multi-day washout runs. Observed about 0.5 days/month in May. Historical risk signal only, not a day-by-day forecast.
0.5 days / month
Probability unavailable
Why this matters
- Expected days 0.5 days / month
- Probability —
- Intensity Up to ~23mm (P95)
Multi-day washout runs are possible on ~0 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Wind High impact
Strong gusts Measures: Strong gust days (>=60 km/h). Observed about 1% of days (0.4 days/month) in May. Historical risk signal only, not a day-by-day forecast.
0.4 days / month
~1% of days
Why this matters
- Expected days 0.4 days / month
- Probability ~1% of days
- Intensity Up to ~73km/h (P95)
Strong gusts are possible on ~0 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Rain Moderate
Heavy rain days Measures: Heavy rain days (>=10mm). Observed about 2% of days (0.8 days/month) in May. Historical risk signal only, not a day-by-day forecast.
0.8 days / month
~2% of days
Why this matters
- Expected days 0.8 days / month
- Probability ~2% of days
- Intensity Up to ~30mm (P95)
Heavy rain is possible on ~1 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Cold Moderate
Cold feels-like nights Measures: Cold feels-like nights (min <=5C). Observed about 1% of days (0.4 days/month) in May. Historical risk signal only, not a day-by-day forecast.
0.4 days / month
~1% of days
Why this matters
- Expected days 0.4 days / month
- Probability ~1% of days
- Intensity Up to ~5°C (P95)
Cold feels-like nights are possible on ~0 days. Long outdoor blocks become harder to sustain, so layer up and keep a warm indoor fallback nearby.
Rain Minor
Wet days Measures: Wet days (>=0.1mm). Observed about 34% of days (10.6 days/month) in May. Historical risk signal only, not a day-by-day forecast.
10.6 days / month
~34% of days
Why this matters
- Expected days 10.6 days / month
- Probability ~34% of days
- Intensity Up to ~12mm (P95)
Measurable rain is possible on ~11 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Cloud Minor
Cloudy days Measures: Cloudy days (cloud cover >=60%). Observed about 34% of days (10.5 days/month) in May. Historical risk signal only, not a day-by-day forecast.
10.5 days / month
~34% of days
Why this matters
- Expected days 10.5 days / month
- Probability ~34% of days
- Intensity Up to ~99% (P95)
Cloudy skies are possible on ~11 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Humidity Minor
High humidity Measures: High humidity days (RH >=80%). Observed about 32% of days (10.0 days/month) in May. Historical risk signal only, not a day-by-day forecast.
10.0 days / month
~32% of days
Why this matters
- Expected days 10.0 days / month
- Probability ~32% of days
- Intensity Up to ~90% (P95)
High humidity is possible on ~10 days. Comfort and pace can drop quickly, so plan shorter outdoor blocks with air-conditioned backup stops.
Rain Minor
Rainy hours Measures: Rain-hours signal (>=3h rain). Observed about 24% of days (7.5 days/month) in May. Historical risk signal only, not a day-by-day forecast.
7.5 days / month
~24% of days
Why this matters
- Expected days 7.5 days / month
- Probability ~24% of days
- Intensity Up to ~19h (P95)
Several rainy hours are possible on ~7 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Wind Minor
Gusty days Measures: Gusty days (>=40 km/h). Observed about 24% of days (7.4 days/month) in May. Historical risk signal only, not a day-by-day forecast.
7.4 days / month
~24% of days
Why this matters
- Expected days 7.4 days / month
- Probability ~24% of days
- Intensity Up to ~59km/h (P95)
Gusty conditions are possible on ~7 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Cloud Minor
Mostly cloudy days Measures: Mostly cloudy days (cloud cover >=80%). Observed about 16% of days (4.8 days/month) in May. Historical risk signal only, not a day-by-day forecast.
4.8 days / month
~16% of days
Why this matters
- Expected days 4.8 days / month
- Probability ~16% of days
- Intensity Up to ~100% (P95)
Mostly cloudy skies are possible on ~5 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Rain Minor
Wet most of day Measures: Wet-most-of-day signal (>=6h rain). Observed about 15% of days (4.8 days/month) in May. Historical risk signal only, not a day-by-day forecast.
4.8 days / month
~15% of days
Why this matters
- Expected days 4.8 days / month
- Probability ~15% of days
- Intensity Up to ~21h (P95)
Wet-most-of-day conditions are possible on ~5 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Cloud Minor
Overcast days Measures: Overcast days (cloud cover >=95%). Observed about 4% of days (1.3 days/month) in May. Historical risk signal only, not a day-by-day forecast.
1.3 days / month
~4% of days
Why this matters
- Expected days 1.3 days / month
- Probability ~4% of days
- Intensity Up to ~100% (P95)
Overcast skies are possible on ~1 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Wind Minor
Breezy days Measures: Breezy days (mean wind >=25 km/h). Observed about 3% of days (0.8 days/month) in May. Historical risk signal only, not a day-by-day forecast.
0.8 days / month
~3% of days
Why this matters
- Expected days 0.8 days / month
- Probability ~3% of days
- Intensity Up to ~32km/h (P95)
Breezy conditions are possible on ~1 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Visibility Minor
Fog-likely signal Measures: Fog-likely visibility proxy. Observed about 1% of days (0.3 days/month) in May. Historical risk signal only, not a day-by-day forecast.
0.3 days / month
~1% of days
Why this matters
- Expected days 0.3 days / month
- Probability ~1% of days
- Intensity Up to ~93% (P95)
Fog-likely conditions are possible on ~0 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Other Minor
Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data Measures: Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data. Observed about 1% of days (0.3 days/month) in May. Historical risk signal only, not a day-by-day forecast.
0.3 days / month
~1% of days
Why this matters
- Expected days 0.3 days / month
- Probability ~1% of days
- Intensity Up to ~93 (P95)
Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data is possible on ~0 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Frequently asked questions
Is May a good time to visit Istanbul?
Typical May days in Istanbul reach highs of 20°C (68°F) with nights around 14°C (57°F). It usually feels mild by day and cool after dark. Overall, May sits in the middle of the Istanbul climate range.
What are temperatures like in May?
In May, you can usually expect highs of 20°C (68°F) and lows near 14°C (57°F). That means mild days and cool nights, so pack layers you can add or remove.
How much does it rain in May?
Rainfall in May averages 37 mm (1.5 in) across roughly 8 days. Overall it is a moderately wet time of year, so showers are usually brief rather than all-day downpours.
How many hours of daylight are there in May?
You can expect about 14 hours of daylight in May. Sunrise is typically around 05:46 and sunset near 20:15. You get long days with comfortable amounts of daylight.
How strong is the sun in May?
UV levels are often high (around 7). Regular sunscreen and a hat are recommended.
Is it windy in May?
In May, average wind speeds are around 13 km/h (8 mph), with gusts on the windiest days reaching about 48 km/h (30 mph). On the ground, it is it often feels breezy, especially in more exposed spots or along the coast.