Knysna in Summer
In summer (December, January and February), Knysna sees average daytime highs around 23°C and overnight lows near 17°C, with 139 mm of rain over about 26 wet days across the season. It is the warmest season of the year and the driest season of the year.
Over the season highs climb from about 21°C in early December to 23°C by late February. The sky is clear or mostly clear about 49% of the time across summer, and the air most often feels humid.
Summer is Knysna's best season of the year to visit on our travel score. For the whole year in context, see Knysna's year-round climate.
- Avg daytime high
- 23°C
- warmest season of the year
- Avg overnight low
- 17°C
- Rainfall
- 139 mm
- 26 wet days
- Avg wind
- 14 km/h
- Travel score
- 7.2
- best season of the year
- Months
- Dec · Jan · Feb
Temperature in Knysna in Summer
Over the season highs climb from about 21°C in early December to 23°C by late February.
A typical summer day in Knysna reaches about 23°C and drops to 17°C overnight. The warmest of the three months is February, the coolest December.
Knysna weather by month
How the three summer months (December, January and February) 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 | 23° / 17° | 49 | 9.2 | 14 | 7.3 |
| Feb | 23° / 18° | 42 | 7.9 | 13.3 | 7.4 |
| Mar | 22° / 17° | 52 | 8.5 | 12.3 | 7.3 |
| Apr | 21° / 14° | 52 | 7.8 | 11.2 | 7.0 |
| May | 19° / 12° | 47 | 6.7 | 10.3 | 6.9 |
| Jun | 18° / 11° | 43 | 7.2 | 9.8 | 6.5 |
| Jul | 17° / 10° | 46 | 7.6 | 10 | 6.2 |
| Aug | 17° / 10° | 62 | 8.8 | 10.7 | 6.0 |
| Sep | 18° / 11° | 49 | 8.5 | 11.8 | 6.2 |
| Oct | 19° / 13° | 62 | 8.9 | 12.9 | 6.4 |
| Nov | 20° / 14° | 70 | 9.3 | 13.8 | 6.6 |
| Dec | 22° / 16° | 47 | 9.3 | 14.2 | 7.0 |
Cloud cover in Summer
The sky is clear or mostly clear about 49% of the time across summer.
Chance of precipitation in Summer
Knysna gets around 139 mm of rain over 26 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels humid — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 14 km/h across summer.
Sunrise & sunset in Summer
Daylight runs from about 14 h 06 min in early December to 12 h 48 min by late February. 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 7.1 kWh/m².
Is summer a good time to visit Knysna?
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 one of the better times to visit Knysna for general sightseeing.
What to pack for Knysna in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Knysna sees daytime highs around 23°C and nights near 17°C. Pack sun protection. Worth having: light clothes and rain gear. About 26 days see rain.
Sea temperature near Knysna in Summer
The nearest coast averages about 21°C across summer — the other half of the beach question. The full-year curve and swim-comfort zones are below.
The sea offshore is warmest in January at about 21°C and coldest in August near 17°C.
It's comfortable for a long swim from Dec 20 to Mar 14 — about 2.8 months when the water holds above 20°C.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 21 | 21 | 20 | 18 | 18 | 17 | 17 | 17 | 17 | 17 | 18 | 20 |
| Comfort | Refreshing | Refreshing | Refreshing | Cool | Cool | Cool | Cool | Cool | Cool | Cool | Cool | Cool |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 21 | Refreshing |
| Feb | 21 | Refreshing |
| Mar | 20 | Refreshing |
| Apr | 18 | Cool |
| May | 18 | Cool |
| Jun | 17 | Cool |
| Jul | 17 | Cool |
| Aug | 17 | Cool |
| Sep | 17 | Cool |
| Oct | 17 | Cool |
| Nov | 18 | Cool |
| Dec | 20 | Cool |
UV index in Knysna in Summer
Clear-sky midday UV across summer averages around 12 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Knysna peaks around January 15 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 23 at about 3 (moderate).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 10 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 13 | 11 | 9 | 6 | 4 | 3 | 3 | 4 | 6 | 10 | 11 | 12 |
| Level | Extreme | Extreme | Very high | High | Moderate | Moderate | Moderate | Moderate | High | Extreme | Extreme | Extreme |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 13 | Extreme |
| Feb | 11 | Extreme |
| Mar | 9 | Very high |
| Apr | 6 | High |
| May | 4 | Moderate |
| Jun | 3 | Moderate |
| Jul | 3 | Moderate |
| Aug | 4 | Moderate |
| Sep | 6 | High |
| Oct | 10 | Extreme |
| Nov | 11 | Extreme |
| Dec | 12 | Extreme |
Where is Knysna?
Knysna sits at 34.0°S, 23.0°E, 9 m above sea level, in South Africa. The nearest listed city is Plettenberg Bay, 30 km away.
Topography around Knysna
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Knysna.
Within 3 km, the terrain around Knysna has significant variations in elevation — a maximum elevation change of 288 m around an average of 64 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 929 m; within 80 km, very significant variations in elevation — a maximum elevation change of 2,052 m.
The land around Knysna is covered by trees (41%) and water (20%) within 3 km, trees (45%) and water (34%) within 16 km, and water (36%) and grassland (31%) within 80 km.
South Africa travel facts
- Travel advisory
- Level 2
- Exercise Increased Caution
- Power plugs
- Type C / M / N
- 230 V · 50 Hz
- Prices
- ≈ 41% of US
- price level, 2025
- GDP per capita
- $6,598
- 2025
- Happiness
- 5.0 / 10
- World Happiness, 2025
- Safe drinking water
- 68%
- of population, 2024
- Homicide rate
- 43.7
- per 100k, 2022
- Road deaths
- 22.2
- per 100k/yr, 2019
- Income group
- Upper middle
- World Bank
- English
- Very high
- EF EPI 602
- 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 Knysna (-34.0363°, 23.0471°, elevation 9 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.