Sylhet in Summer
In summer (June, July and August), Sylhet sees average daytime highs around 31°C and overnight lows near 25°C, with 2627 mm of rain over about 91 wet days across the season. It is the warmest season of the year and the wettest season of the year.
Across summer, daytime highs hold fairly steady around 31°C. The sky is clear or mostly clear about 3% of the time across summer, and the air most often feels miserable.
Summer is Sylhet's weakest season of the year to visit on our travel score. For the whole year in context, see Sylhet's year-round climate.
- Avg daytime high
- 31°C
- warmest season of the year
- Avg overnight low
- 25°C
- Rainfall
- 2627 mm
- 91 wet days
- Avg wind
- 5 km/h
- Travel score
- 2.4
- weakest season of the year
- Months
- Jun · Jul · Aug
Temperature in Sylhet in Summer
Across summer, daytime highs hold fairly steady around 31°C.
A typical summer day in Sylhet reaches about 31°C and drops to 25°C overnight. The warmest of the three months is August, the coolest June.
How summer really feels in Sylhet
Once humidity and wind are folded in, summer brings about 92 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.
Sylhet 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 | 24° / 11° | 10 | 1.8 | 10.6 | 9.0 |
| Feb | 26° / 14° | 48 | 4.6 | 11.1 | 8.2 |
| Mar | 29° / 18° | 187 | 11.2 | 11.8 | 6.1 |
| Apr | 29° / 21° | 560 | 21.4 | 12.6 | 4.0 |
| May | 30° / 23° | 759 | 27.6 | 13.2 | 3.1 |
| Jun | 30° / 25° | 953 | 29.5 | 13.5 | 2.5 |
| Jul | 31° / 25° | 941 | 30.8 | 13.4 | 2.3 |
| Aug | 31° / 26° | 733 | 30.7 | 12.9 | 2.3 |
| Sep | 31° / 25° | 523 | 27.6 | 12.2 | 2.6 |
| Oct | 30° / 23° | 217 | 14.8 | 11.4 | 4.7 |
| Nov | 28° / 17° | 28 | 2.3 | 10.8 | 7.8 |
| Dec | 25° / 13° | 12 | 1.1 | 10.5 | 9.1 |
Cloud cover in Summer
The sky is clear or mostly clear about 3% of the time across summer.
Chance of precipitation in Summer
Sylhet gets around 2627 mm of rain over 91 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels miserable — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 5 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 3.4 kWh/m².
Hazard calendar for Sylhet
In summer, Sylhet overlaps its monsoon season. The full year is below, with each hazard's peak months called out.
Sylhet's monsoon runs April–September, when most of the year's rain falls.
Is summer a good time to visit Sylhet?
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 Sylhet.
What to pack for Sylhet in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Sylhet sees daytime highs around 31°C and nights near 25°C. Pack light clothes and rain gear. About 91 days see rain.
UV index in Sylhet in Summer
Clear-sky midday UV across summer averages around 9 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Sylhet peaks around July 21 at about 12 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near January 17 at about 4 (moderate).
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) | 4 | 5 | 8 | 7 | 8 | 6 | 12 | 10 | 11 | 6 | 6 | 5 |
| Level | Moderate | Moderate | Very high | High | Very high | High | Extreme | Extreme | Extreme | High | High | Moderate |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 4 | Moderate |
| Feb | 5 | Moderate |
| Mar | 8 | Very high |
| Apr | 7 | High |
| May | 8 | Very high |
| Jun | 6 | High |
| Jul | 12 | Extreme |
| Aug | 10 | Extreme |
| Sep | 11 | Extreme |
| Oct | 6 | High |
| Nov | 6 | High |
| Dec | 5 | Moderate |
Air quality in Sylhet 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 Sylhet is worst in January — around 100 µg/m³ PM2.5 (unhealthy), about 4.3× the cleanest month (July, 23 µg/m³).
Seasonal pattern from CAMS reanalysis, scaled to Sylhet's WHO annual average of 59.8 µg/m³.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 100 | 94 | 95 | 62 | 44 | 32 | 23 | 30 | 36 | 51 | 67 | 83 |
| Level | Unhealthy | Unhealthy | Unhealthy | Unhealthy | Poor | Moderate | Moderate | Moderate | Poor | Poor | Unhealthy | Unhealthy |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 100 | Unhealthy |
| Feb | 94 | Unhealthy |
| Mar | 95 | Unhealthy |
| Apr | 62 | Unhealthy |
| May | 44 | Poor |
| Jun | 32 | Moderate |
| Jul | 23 | Moderate |
| Aug | 30 | Moderate |
| Sep | 36 | Poor |
| Oct | 51 | Poor |
| Nov | 67 | Unhealthy |
| Dec | 83 | Unhealthy |
Where is Sylhet?
Sylhet sits at 24.9°N, 91.9°E, 26 m above sea level, in Bangladesh. The nearest listed city is Mymensingh, 149 km away.
Topography around Sylhet
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Sylhet.
Within 3 km, the terrain around Sylhet has only modest variations in elevation — a maximum elevation change of 55 m around an average of 19 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 82 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,953 m.
The land around Sylhet is covered by trees (52%) and artificial surfaces (41%) within 3 km, cropland (53%) and trees (39%) within 16 km, and trees (46%) and cropland (40%) within 80 km.
Bangladesh travel facts
- Travel advisory
- Level 3
- Reconsider Travel
- Power plugs
- Type A / C / D / G
- 220 V · 50 Hz
- Prices
- ≈ 25% of US
- price level, 2025
- GDP per capita
- $2,597
- 2025
- Happiness
- 4.3 / 10
- World Happiness, 2025
- Safe drinking water
- 59%
- of population, 2024
- Homicide rate
- 2.3
- per 100k, 2018
- Road deaths
- 15.3
- per 100k/yr, 2019
- Income group
- Lower middle
- World Bank
- English
- Moderate
- EF EPI 506
- 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 Sylhet (24.899°, 91.872°, elevation 26 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.