Yilan in Summer
In summer (June, July and August), Yilan sees average daytime highs around 29°C and overnight lows near 25°C, with 919 mm of rain over about 71 wet days across the season. It is the warmest season of the year and the 2nd-wettest season.
Across summer, daytime highs hold fairly steady around 29°C. The sky is clear or mostly clear about 15% of the time across summer, and the air most often feels oppressive.
Summer is Yilan's weakest season of the year to visit on our travel score. For the whole year in context, see Yilan's year-round climate.
- Avg daytime high
- 29°C
- warmest season of the year
- Avg overnight low
- 25°C
- Rainfall
- 919 mm
- 71 wet days
- Avg wind
- 6 km/h
- Travel score
- 3.7
- weakest season of the year
- Months
- Jun · Jul · Aug
Temperature in Yilan in Summer
Across summer, daytime highs hold fairly steady around 29°C.
A typical summer day in Yilan reaches about 29°C and drops to 25°C overnight. The warmest of the three months is July, the coolest June.
How summer really feels in Yilan
Once humidity and wind are folded in, summer brings about 75 days that feel above 32°C and 0 that feel at or below 0°C.
The story in summer is heat — humidity pushes the afternoon "feels like" well above the raw temperature.
Yilan weather by month
How the three summer months (June, July and August) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 17° / 13° | 190 | 22 | 10.6 | 3.6 |
| Feb | 17° / 13° | 164 | 19.7 | 11.1 | 3.9 |
| Mar | 19° / 15° | 152 | 19.9 | 11.8 | 4.6 |
| Apr | 22° / 18° | 185 | 20.8 | 12.6 | 4.8 |
| May | 25° / 21° | 297 | 25.2 | 13.2 | 4.3 |
| Jun | 28° / 24° | 319 | 25.3 | 13.5 | 3.6 |
| Jul | 30° / 25° | 271 | 22.3 | 13.4 | 3.7 |
| Aug | 29° / 25° | 329 | 22.9 | 12.9 | 3.7 |
| Sep | 27° / 24° | 336 | 20.5 | 12.2 | 4.6 |
| Oct | 24° / 21° | 394 | 21.6 | 11.4 | 4.9 |
| Nov | 21° / 18° | 336 | 21 | 10.8 | 4.6 |
| Dec | 18° / 14° | 244 | 21.7 | 10.5 | 4.1 |
Cloud cover in Summer
The sky is clear or mostly clear about 15% of the time across summer.
Chance of precipitation in Summer
Yilan gets around 919 mm of rain over 71 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels oppressive — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 6 km/h across summer.
Sunrise & sunset in Summer
Daylight runs from about 13 h 24 min in early June to 12 h 30 min by late August. The lit band spans sunrise to sunset each day.
Solar energy in Summer
Average shortwave solar energy reaching the ground each day across summer, about 5.4 kWh/m².
Hazard calendar for Yilan
In summer, Yilan overlaps its pacific typhoon season. The full year is below, with each hazard's peak months called out.
Yilan sits in the Pacific typhoon belt; the season peaks July–October.
Is summer a good time to visit Yilan?
Our two travel scores rate summer for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
summer is a weaker month for outdoor sightseeing in Yilan.
What to pack for Yilan in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Yilan sees daytime highs around 29°C and nights near 25°C. Pack light clothes and rain gear. Worth having: sun protection. About 71 days see rain.
Sea temperature near Yilan in Summer
The nearest coast averages about 28°C across summer — the other half of the beach question. The full-year curve and swim-comfort zones are below.
The sea at the nearest coast (about 18 km away) is warmest in August at about 28°C and coldest in January near 22°C.
The water stays above 20°C all year — warm enough for a swim any month.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 22 | 22 | 23 | 24 | 26 | 27 | 28 | 28 | 28 | 26 | 25 | 23 |
| Comfort | Refreshing | Refreshing | Refreshing | Warm | Warm | Warm | Tropical | Tropical | Warm | Warm | Warm | Refreshing |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 22 | Refreshing |
| Feb | 22 | Refreshing |
| Mar | 23 | Refreshing |
| Apr | 24 | Warm |
| May | 26 | Warm |
| Jun | 27 | Warm |
| Jul | 28 | Tropical |
| Aug | 28 | Tropical |
| Sep | 28 | Warm |
| Oct | 26 | Warm |
| Nov | 25 | Warm |
| Dec | 23 | Refreshing |
UV index in Yilan in Summer
Clear-sky midday UV across summer averages around 11 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Yilan peaks around July 14 at about 11 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 21 at about 5 (high).
The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 6 | 8 | 9 | 7 | 10 | 11 | 12 | 10 | 11 | 8 | 7 | 5 |
| Level | High | Very high | Very high | High | Extreme | Extreme | Extreme | Very high | Extreme | Very high | High | Moderate |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 6 | High |
| Feb | 8 | Very high |
| Mar | 9 | Very high |
| Apr | 7 | High |
| May | 10 | Extreme |
| Jun | 11 | Extreme |
| Jul | 12 | Extreme |
| Aug | 10 | Very high |
| Sep | 11 | Extreme |
| Oct | 8 | Very high |
| Nov | 7 | High |
| Dec | 5 | Moderate |
Air quality in Yilan in Summer
Average fine-particle pollution (PM2.5) through the year — so you can see where summer falls, not just the annual average.
Air quality in Yilan is worst in April — around 52 µg/m³ PM2.5 (poor), about 2.1× the cleanest month (October, 25 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 38 | 43 | 51 | 52 | 44 | 41 | 32 | 32 | 30 | 25 | 32 | 32 |
| Level | Poor | Poor | Poor | Poor | Poor | Poor | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 38 | Poor |
| Feb | 43 | Poor |
| Mar | 51 | Poor |
| Apr | 52 | Poor |
| May | 44 | Poor |
| Jun | 41 | Poor |
| Jul | 32 | Moderate |
| Aug | 32 | Moderate |
| Sep | 30 | Moderate |
| Oct | 25 | Moderate |
| Nov | 32 | Moderate |
| Dec | 32 | Moderate |
Where is Yilan?
Yilan sits at 24.8°N, 121.8°E, 15 m above sea level, in Taiwan. The nearest listed city is Xizhi, 36 km away.
Topography around Yilan
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Yilan.
Within 3 km, the terrain around Yilan has only modest variations in elevation — a maximum elevation change of 33 m around an average of 9 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,413 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,839 m.
The land around Yilan is covered by cropland (40%), artificial surfaces (35%) and trees (21%) within 3 km, trees (50%) and water (23%) within 16 km, and trees (47%) and water (46%) within 80 km.
Taiwan travel facts
- Travel advisory
- Level 1
- Exercise Normal Precautions
- Power plugs
- Type A / B
- 110 / 220 V · 60 Hz
- Happiness
- 6.7 / 10
- World Happiness, 2025
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Yilan (24.757°, 121.753°, elevation 15 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google.