UV index for Johannesburg peaks at UV 10 at 12:00 local time. Data as of (Africa/Johannesburg). Values update hourly — see this page for the current reading and hourly forecast.

uvi·today

UV Index in Johannesburg

Live UV index for Johannesburg, South Africa — current level, hourly UV forecast, peak times, WHO sun protection advice and a 4-day outlook. Now: UV 8 (Very High). Peak today: UV 10 at 12:00.

Now · 10:00 · Johannesburg
8
Very High
0–2Low3–5Moderate6–7High8–10Very High11+Extreme

Sun protection needed today: 08:00–15:00

Protection guidelines:

Now · 10:00 — UV 8 · Very High · Clear sky: 9

  • Avoid being outside during midday hours
  • Make sure you seek shade
  • Shirt, broad-spectrum sunscreen and hat are a must
Values are forecasts from the European CAMS model (Copernicus), not measurements from a sensor in Johannesburg. WHO · Methodology
Today's UV overview · Fri, Oct 16
1
7Clear sky17°56%0
3
8Clear sky21°43%0
6
9Clear sky24°36%1
8
10Mainly clear26°32%1
9
11Partly cloudy28°27%2
10
12Partly cloudy28°25%2
8
13Partly cloudy29°24%3
5
14Overcast29°24%2
2
15Partly cloudy29°23%2
1
16Overcast29°23%2
% HumidityWind m/s
Max today
10at 12:00
Max tomorrow
11at 12:00
Daylight today
12h 44m05:31–18:15
Solar noon
11:53

Sun & moon in Johannesburg

Sun height68°
Sun directionNE 40°
Sky stateDaylight
-90°-60°-30°0°30°60°90°00:0006:0012:0018:0024:00Now 68°

The curve traces the sun's height above the horizon through the day: 0° is the horizon, 90° is straight overhead. The higher the sun climbs, the shorter the path its rays take through the atmosphere — and the stronger the UV. The part below 0° is night.

Sunrise / sunset directionE 100° / W 260°
Civil twilight05:08–05:32 / 18:14–18:38
Nautical twilight04:40–05:08 / 18:38–19:06
Astronomical twilight04:12–04:40 / 19:06–19:34
Moon phaseWaxing crescent · 29%
Moonrise / moonset09:16 / 23:44
Next moon quarterFirst quarter · Oct 18, 18:13

Detailed hourly UV index — Today, Oct 16

Peak UV 9.7 at 12:00 · Johannesburg · Local time (GMT+2)

The solid line is the hourly UV forecast: the UV index expected each hour, with cloud cover taken into account. The dashed line is the clear-sky UV, the level it would reach under a cloudless sky. The gap between the two lines shows how much the clouds are lowering the UV.

048Max: 10Now: 86:0015°9:0024°12:0028°15:0029°18:0026°21:0022°
ForecastClear sky

Detailed hourly UV index — Tomorrow, Oct 17

Peak UV 11 at 12:00 · Johannesburg · Local time (GMT+2)

04812Max: 116:0017°9:0025°12:0029°15:0029°18:0026°21:0023°
ForecastClear sky
Hour-by-hour UV index for today & tomorrow

Detailed hour-by-hour UV index forecast for Johannesburg — today and tomorrow. Includes UV level, clear-sky UV, weather conditions, and temperature for each hour.

Today — Oct 16

HourUVClear skyWeather
05:000.0 – Low0.0Clear sky15°
06:000.2 – Low0.2Clear sky15°
07:001.0 – Low1.0Clear sky17°
08:003.0 – Moderate3.0Clear sky21°
09:005.8 – High5.8Clear sky24°
10:008.0 – Very High8.7Mainly clear26°
11:009.3 – Very High10.6Partly cloudy28°
12:009.7 – Very High10.7Partly cloudy28°
13:007.7 – Very High9.1Partly cloudy29°
14:005.4 – Moderate6.5Overcast29°
15:002.5 – Low3.7Partly cloudy29°
16:000.8 – Low1.6Overcast29°
17:000.2 – Low0.4Overcast28°
18:000.0 – Low0.0Partly cloudy26°
19:000.0 – Low0.0Partly cloudy24°
20:000.0 – Low0.0Partly cloudy23°
21:000.0 – Low0.0Partly cloudy22°

Tomorrow — Oct 17

HourUVClear skyWeather
05:000.0 – Low0.0Mainly clear17°
06:000.2 – Low0.2Mainly clear17°
07:001.0 – Low1.0Mainly clear18°
08:003.0 – Moderate3.0Clear sky22°
09:005.9 – High5.9Mainly clear25°
10:008.9 – Very High8.9Mainly clear27°
11:0010.9 – Extreme10.9Partly cloudy28°
12:0011.0 – Extreme11.2Partly cloudy29°
13:009.1 – Very High9.8Overcast29°
14:006.4 – High7.0Overcast30°
15:003.1 – Moderate4.1Overcast29°
16:001.5 – Low1.7Overcast28°
17:000.4 – Low0.5Overcast28°
18:000.0 – Low0.0Partly cloudy26°
19:000.0 – Low0.0Partly cloudy24°
20:000.0 – Low0.0Partly cloudy23°
21:000.0 – Low0.0Partly cloudy23°

4-Day UV Forecast for Johannesburg

The 4-day UV index forecast shows each day's peak UV and the time it's reached, plus daily high and low temperatures and an hourly UV curve, so you can plan sun protection for the days ahead.

Today, Oct 16Peak UV 10 at 12:00Sun protection: 08:00–15:0029° / 15°
6Clear sky15°9Clear sky24°12Partly cloudy28°15Partly cloudy29°18Partly cloudy26°
Saturday, Oct 17Peak UV 11 at 12:00Sun protection: 08:00–16:0030° / 17°
6Mainly clear17°9Mainly clear25°12Partly cloudy29°15Overcast29°18Partly cloudy26°
Sunday, Oct 18Peak UV 11 at 11:00Sun protection: 08:00–16:0029° / 18°
6Partly cloudy18°9Partly cloudy24°12Partly cloudy28°15Partly cloudy29°18Partly cloudy26°
Monday, Oct 19Peak UV 10 at 11:00Sun protection: 08:00–16:0026° / 11°
6Mainly clear16°9Clear sky21°12Clear sky26°15Clear sky24°18Clear sky19°

Peak midday UV by month in Johannesburg

It's October: on clear days, the midday sun here usually peaks around UV 10–14. That's very intense: around midday you need shade, covering clothes and sunscreen.

The sun is strong here all year round: even in the mildest months, midday UV reaches about 5, so protection is needed in every season. Treat these numbers as the most sun you should expect around noon: clouds typically lower the real value, while reflections from snow, sand or water can add to the UV your skin actually receives. Today's actual UV is in the forecast above.

36811141714–17Jan13–16Feb10–14Mar7–11Apr5–7May4–5Jun4–6Jul5–8Aug8–11Sep10–14Oct12–15Nov14–16Dec

Each bar shows the range the midday UV index moves through on clear days in that month, from the gentlest days up to what the strongest days typically reach, based on 17 years of satellite data (2004–2020). The small light line inside a bar is an ordinary day's midday level.

Based on TEMIS data. Copyright © KNMI/ESA — https://www.temis.nl/

In October the strong sun is in the southern hemisphere: UV reaches high levels across most of it, while the northern hemisphere outside the tropics has its mild season.

See the world map for October →

The UV year at a glance

Strongest sunJan · up to 17
Weakest sunJun · up to 5
Protection needed (UV 3+)all year
Extra protection (UV 8+)Aug–Apr

Months when the midday sun gets strong enough to need protection. Based on clear days; clouds typically lower UV.

See also: Johannesburg temperature and rainfall by month →

UV in Johannesburg: today, tomorrow and through the year

In Johannesburg it's currently UV 8 (very high), and with the day peaking at 10 (very high), protection is worth keeping on until 15:00. Under clear skies, UV climbs close to its full strength. Up at 1,734 m, the thinner air at this altitude lets through more UV than at sea level.UV strengthens tomorrow, topping out at UV 11 (extreme) near 12:00, with protection needed from 08:00 to 16:00.UV in Johannesburg is climbing through October, and the strongest part of the year is still ahead.

Location, daylight and sky in Johannesburg

Key facts

CountrySouth Africa, Gauteng
TimezoneAfrica/Johannesburg (UTC+2)
Coordinates26.20° S, 28.04° E
Elevation1734 m
Population≈ 9.42M
Air pressurebarometer.today

Sun & Daylight Hours in Johannesburg

Sunrise / sunset05:31 / 18:15
Daylight today12h 44m
Daylight tomorrow12h 45m (+1 min)
Solar noon (sun highest)11:53
Golden hour17:44–18:29
Low UV hours (UV < 3)05:00–08:00
15:00–18:00
High UV window (UV ≥ 3)08:00–15:00

Seasonal daylight range at this latitude

Longest day13h 47m (Dec 21)
Shortest day10h 30m (Jun 21)

UV index map for Johannesburg and nearby cities

This map shows the current UV forecast for Johannesburg and the area around it. One forecast value covers a region of roughly 40 km, so it is a good guide for the area as a whole rather than an exact reading for one spot. In places with big height differences, or where the ground is covered by snow, the real UV can differ from what the map shows.

Check UV in: Soweto · Pretoria · Benoni · Thembisa · Vereeniging

Air quality concerns? Check air quality in Johannesburg on AirIndex.Today

What is the UV index in Johannesburg right now?

As of 10:00 local time, the UV index in Johannesburg is 8 (Very High). UV changes hour by hour. See the hourly chart above for how it rises and falls today.

What is the UV index in Johannesburg today?

On 2026-10-16, the peak UV index forecast for Johannesburg is 10, expected around 12:00 local time. Check back daily: UV levels change with cloud cover, ozone, and sun angle. Johannesburg sits at 1734 m elevation, where UV radiation is stronger than at sea level (roughly +10% per 1,000 m).

What is the UV index in Johannesburg tomorrow?

On 2026-10-17, the UV index in Johannesburg is forecast to peak at 11 around 12:00 local time. Plan outdoor activities and sun protection around that peak.

What are typical maximum UV levels in Johannesburg by month?

Peak midday UV index in Johannesburg, month by month
MonthPeak midday UV
January14–17
February13–16
March10–14
April7–11
May5–7
June4–5
July4–6
August5–8
September8–11
October10–14
November12–15
December14–16
The weakest sun is in June, when midday UV stays around 4–5. From there it climbs: July (4–6), August (5–8), September (8–11), October (10–14), November (12–15), and December (14–16). The strongest sun is in January, reaching 14–17 on clear days. It eases back through February (13–16), March (10–14), April (7–11), and May (5–7).Clear-sky range, 17 years of satellite data (2004–2020). On cloudy days values are typically lower.

How strong is UV in Johannesburg in October?

In a typical October, the midday UV index in Johannesburg reaches 10–14 on clear days, based on 17 years of satellite data (2004–2020). Cloudy days typically run lower. Check the live forecast for today's value.

Which months have the highest UV in Johannesburg?

UV in Johannesburg is highest in January, when the midday index reaches up to 17 on clear days. The weakest sun is in June, around 4–5 at midday.

When do you need sun protection in Johannesburg?

All year round: midday UV in Johannesburg reaches 3 or higher (the WHO protection level) in every month. In August–April it can reach UV 8 or more, when the WHO advises extra protection: avoid the midday sun and cover up.

Forecast · UV Index

Now
UV 8 (Very High)
Max today
UV 9.7 · 12:00
Max tomorrow
UV 11 · 12:00
Clear sky
UV 10.7
Sunrise / Sunset
05:31 / 18:15
High UV window (UV ≥ 3)
08:00–15:00
4-Day UV Forecast
Fri 9.7 · Sat 11 · Sun 11.1 · Mon 10.3

UV guides

Read all guides →
About the UV Index

What is the UV index?

The UV index (UVI) is an international standard measure of the strength of ultraviolet radiation from the sun at a particular place and time. It ranges from 0 (nighttime) to 11+ (extreme). Higher values mean greater risk of sunburn, skin damage, and eye injury. The UV index was developed by the World Health Organization (WHO) to help people protect themselves from harmful UV radiation.

How do I check the UV index today?

This page shows the live UV index for your location using data from the Copernicus Atmosphere Monitoring Service (CAMS). You get the current UV level, an hourly UV forecast chart for today and tomorrow, and the exact peak UV time — so you always know when sun protection is most important.

When is UV radiation strongest?

UV radiation is typically strongest between 10:00 and 16:00, when the sun is highest in the sky. However, the exact peak time and intensity depend on your latitude, the season, altitude, cloud cover, and ozone levels. Check the UV forecast chart above to see today's exact peak time for your location.

How can I protect myself from UV radiation?

Apply broad-spectrum sunscreen, wear protective clothing and a wide-brimmed hat, seek shade during peak UV hours, and wear UV-blocking sunglasses. The WHO recommends sun protection when the UV index is 3 or above.

Where does the UV data come from?

The hourly UV index on this site comes from the Copernicus Atmosphere Monitoring Service (CAMS), operated by ECMWF on behalf of the European Union. CAMS calculates the UV biologically effective dose using total column ozone, aerosol optical depth, and cloud cover. The global forecast has a spatial resolution of approximately 40 km and provides hourly UV index values for up to 5 days ahead.

What does "clear-sky UV index" mean?

The clear-sky UV index shows how strong ultraviolet radiation would be if there were no clouds at all. It is calculated using the same atmospheric data — ozone column thickness, aerosol concentrations, and solar angle — but assumes completely cloudless conditions. Comparing the actual UV index with the clear-sky value shows how much clouds are reducing UV exposure at any given time. On overcast days, actual UV can be significantly lower than the clear-sky value.

How often is the UV forecast updated?

The CAMS global UV forecast is updated twice daily, based on model runs initialized at 00:00 and 12:00 UTC. Weather data such as temperature, cloud cover, and sunrise/sunset times is updated every 1–6 hours depending on the region, using weather models from national meteorological services via Open-Meteo. The first 1–2 days of the forecast are typically the most accurate.

What does the WHO recommend for each UV level?

Low (0–2) — No protection needed. You can safely enjoy being outside
Moderate (3–5) — Seek shade during midday hours. Wear a shirt, apply broad-spectrum sunscreen, and put on a hat. Wear UV-blocking sunglasses
High (6–7) — Seek shade during midday hours. Wear a shirt, apply broad-spectrum sunscreen, and put on a hat. Wear UV-blocking sunglasses
Very High (8–10) — Avoid being outside during midday hours. Make sure you seek shade. Shirt, broad-spectrum sunscreen and hat are a must
Extreme (11+) — Avoid being outside during midday hours. Make sure you seek shade. Shirt, broad-spectrum sunscreen and hat are a must

Source: WHO Global Solar UV Index, 2002

uvi·today

Disclaimer: This website is for informational purposes only and does not constitute medical advice, diagnosis, or treatment. UV index data and sun protection guidance are approximate and should not replace professional advice. UV index data is not applicable to infants under 12 months. The WHO recommends keeping them out of direct sunlight at all times. WHO. UV forecasts are based on satellite and atmospheric models. Actual UV levels may vary due to local cloud cover, surface reflection, altitude, and other environmental factors. When in doubt, consult a healthcare provider for personalized sun protection advice. UV and weather data is sourced from third-party APIs (Open-Meteo/CAMS). We do not guarantee accuracy or availability. Data may be delayed or temporarily unavailable.

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UV & weather data: Open-Meteo (CAMS/Copernicus) · Protection guidelines: WHO Global Solar UV Index, 2002 · Location data: GeoNames (CC BY 4.0) · IP2Location LITE · Yr / NRK (CC BY 4.0) · Twemoji (CC BY 4.0)

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