Climate and average weather in Theunissen

In Theunissen, the summers are hot, showery, and mostly clear and the winters are mild and clear.

Best: late March to mid October

Over the course of the year, the temperature in Theunissen typically varies from 2°C to 30°C, and is rarely below -3°C or above 35°C. January is the hottest month of the year, while June is the coldest.

Based on the travel score, the best time of year to visit Theunissen for warm-weather activities is from late March to mid October.

Hottest
Jan
30°
Coldest
Jun
Wettest
Jan
96 mm
Driest
Jul
7 mm
Rain / yr
585 mm
85 wet days
Daylight
10.2–13.8 h
shortest–longest
Elevation
1,406 m
28.4°S
Clearest
Jul
14% cloud

Theunissen is place in Free State, South Africa.

Founded
1907

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Theunissen weather by month, at a glance

The whole year in one picture — sky, rain, humidity, temperature and travel score. Click any band to jump to its full chart.

Each stripe is one measure across the whole year, stacked so a single day reads top to bottom. The sky band runs overcast grey on top down to clear blue at the base — more blue means sunnier — followed by the rainfall curve, the humidity band, a temperature strip that tints each stretch of the year by how warm its average high is, and the travel-score line at the foot. Scan straight down any date to read that day across every measure at once; the score climbs highest around late March to mid October.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

Daily average highs and lows in Theunissen, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.

The hot season lasts 5.3 months, from October 9 to March 18, with daily high temperatures above 27°C. The hottest month of the year in Theunissen is January, with an average high of 30°C and low of 17°C.

The cool season lasts 2.5 months, from May 25 to August 9, with daily high temperatures below 20°C. The coldest month of the year in Theunissen is June, with an average low of 2°C and high of 18°C.

Days typically run about 15°C warmer than nights, with the widest day–night swing (around 17°C) in August.

10°20°30°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan3017
Feb2917
Mar2715
Apr2411
May216
Jun182
Jul182
Aug214
Sep259
Oct2712
Nov2814
Dec3016

How hot and cold Theunissen really feels

Feels-like highFeels-like lowactual air temp

The felt-temperature range through the year — heat index on the day's high (summer humidity), wind chill on the night's low (winter wind). The dashed lines are the plain thermometer; the gap is how much hotter or colder it really feels.

On the coldest nights, wind chill pulls the feels-like down to about -2°C (around July 10), with roughly 61 freezing days a year (feels-like at or below 0°C), worst in July.

10°20°30°JanFebMarAprMayJunJulAugSepOctNovDec
Feels-like high (°C)Air high (°C)Feels-like low (°C)Air low (°C)
Jan30301717
Feb29291717
Mar27271515
Apr24241011
May212146
Jun1818-12
Jul1818-12
Aug212124
Sep252579
Oct27271212
Nov28281414
Dec30301616

Average hourly temperature in Theunissen

A compact picture of the whole year, hour by hour: each column is a day, each row an hour, and the color is the modeled average temperature. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

Read left to right for the day of the year and top to bottom for the hour of the day; the color is the modeled temperature, cool blues through to hot reds on the same scale as the other charts. A vertical slice is a single day's swing — coolest just before dawn, warmest in the mid-afternoon — while a horizontal slice follows one hour across the seasons. The darker overlay marks night and the lighter one the twilight around sunrise and sunset. Colors run warmest on January afternoons, near 30°C, and coldest before dawn in June, near C.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM

Theunissen weather by month

Every month at a glance. Click a month for its detailed page.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan30° / 17°9613.613.64.9
Feb29° / 17°7911.8135.4
Mar27° / 15°7510.612.26.6
Apr24° / 11°497.411.37.7
May21° / 213.310.68.2
Jun18° / 121.810.27.8
Jul18° / 71.310.48.0
Aug21° / 162.4118.5
Sep25° / 142.611.88.6
Oct27° / 12°527.812.77.2
Nov28° / 14°769.513.46.0
Dec30° / 16°8912.913.85.0

Chance of rain

How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.

Theunissen gets about 585 mm of precipitation a year. On a typical day the chance of rain is some rain, but that rises and falls sharply with the seasons.

The wetter season lasts 6.3 months, from around Oct 14 to Apr 22, peaking in January at about 46% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Jul 9.

January is the wettest month by volume, with 96 mm over about 14 wet days; July is the driest, with 7 mm.

0%10%20%30%40%50%60%JanFebMarAprMayJunJulAugSepOctNovDecwetterdrierwettermostly drysome rainoften wetvery wetJan 22 · 46%Jul 9 · 4%
Rain on a day (%)Rain days
Jan4414
Feb4312
Mar3411
Apr257
May103
Jun62
Jul51
Aug72
Sep103
Oct248
Nov3310
Dec4113

Monthly rainfall

Over a full year, Theunissen collects about 585 mm of rain across 85 wet days — roughly 49 mm in an average month.

It doesn’t fall evenly. January is the wettest month with 96 mm, while July is the driest at just 7 mm. The three wettest months alone bring about 45% of the year’s total.

0255075100125JanFebMarAprMayJunJulAugSepOctNovDec96797549211271614527689
Rainfall (mm)Rain days
Jan9614
Feb7912
Mar7511
Apr497
May213
Jun122
Jul71
Aug162
Sep143
Oct528
Nov7610
Dec8913

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

How often the daytime sky is clear, partly cloudy or overcast.

In Theunissen, the average share of the sky covered by clouds shows moderate seasonal variation over the course of the year.

The clearer part of the year begins around April 26 and lasts for 4.9 months, ending around September 22. The clearest month is July, when the sky is clear, mostly clear, or partly cloudy 92% of the time on average.

The cloudier part of the year begins around September 23 and lasts for 7.1 months, ending around April 25. The cloudiest month is November, when it is overcast or mostly cloudy 30% of the time.

0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%JanFebMarAprMayJunJulAugSepOctNovDecJul 13 · 94%Dec 1 · 68%clearmostly clearpartly cloudymostly cloudyovercastcloudierclearercloudier
Clearer (%)Cloudier (%)
Jan7426
Feb7525
Mar7624
Apr7822
May8317
Jun9010
Jul928
Aug8911
Sep8218
Oct7525
Nov7030
Dec7228

Daylight, sunrise and sunset

DaylightNight

Hours of daylight through the year, with sunrise and sunset times.

The gold band is daylight — sunrise runs along its lower edge, sunset along the upper — so it widens toward summer and pinches toward winter, with night the dark area above and below. The longest day, around January 1, brings about 13 h 48 min of light; the shortest, around June 9, only 10 h 12 min — a swing of roughly 3 h 36 min.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan13.65:347:11
Feb13.05:576:58
Mar12.26:176:29
Apr11.36:345:53
May10.66:525:27
Jun10.27:075:20
Jul10.47:085:29
Aug11.06:485:47
Sep11.86:136:03
Oct12.75:376:19
Nov13.45:156:42
Dec13.85:157:03

Sunny days

How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.

Theunissen averages about 19 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 14 and 26 days.

The sunnier stretch runs 5.1 months, from around Apr 25 to Sep 27. The sunniest month is July, with roughly 26 sunny days (brilliant).

The greyest month is December, down near 14 sunny days — about 45% fewer than the July peak.

051015202530JanFebMarAprMayJunJulAugSepOctNovDecgreyersunniergreyergloomymixedbrightbrilliantJul 1626 daysDec 814 days
Sunny daysSky
Jan15Mixed
Feb14Bright
Mar17Bright
Apr18Bright
May23Bright
Jun24Brilliant
Jul26Brilliant
Aug25Brilliant
Sep21Bright
Oct17Bright
Nov15Bright
Dec14Mixed

Humidity comfort

DryComfortableHumidMuggyOppressiveMiserable

Share of days at each humidity comfort level, based on the dew point — the measure that tracks how muggy it actually feels.

Humidity comfort is graded by the dew point — the temperature at which the air would be fully saturated — because it tracks how muggy it actually feels far better than relative humidity does. A low dew point feels dry and crisp; a high one feels sticky and oppressive no matter the reading on a humidity gauge.

In Theunissen, how humid it feels changes noticeably over the year.

The more humid part of the year lasts 3.2 months, from around December 15 to March 22. The muggiest month is January, when the air feels humid, muggy or worse about 20% of the time.

The most comfortable stretch runs from around March 23 to December 14, and April is the most comfortable month — the air is dry or comfortable 99% of the time.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDecApr 17 · 100%Jan 29 · 74%humidcomfortabledryhumidcomfortable
Dry (%)Comfortable (%)Humid (%)
Jan443620
Feb364123
Mar57358
Apr90101
May10000
Jun10000
Jul10000
Aug10000
Sep10000
Oct9370
Nov83152
Dec63307

Wind

Average wind speed through the year, banded into plain-language speed zones so a number reads as 'breezy' or 'calm' without knowing the scale.

This is the average sustained wind speed at the standard 10 metres above open ground — the steady flow a weather station reports, not the sharper gusts that come and go, which can run half again as fast. It's the number that says whether a place is generally breezy or calm.

Across the year, average wind speed in Theunissen is typically calm, near 11 km/h, and varies little with the seasons.

The windier part of the year lasts 5.7 months, from around Aug 10 to Jan 30. The windiest month is November, averaging about 13 km/h (light breeze).

The calmer part of the year runs from around Jan 31 to Aug 9, with May the calmest month at about 9 km/h.

05101520JanFebMarAprMayJunJulAugSepOctNovDecwindiercalmerwindiercalmlight breezeNov 19 · 13 km/hMay 14 · 9 km/h
Wind speed (km/h)Feels
Jan11calm
Feb10calm
Mar10calm
Apr9calm
May9calm
Jun9calm
Jul10calm
Aug11calm
Sep12light breeze
Oct13light breeze
Nov13light breeze
Dec12light breeze

Hazard calendar for Theunissen

In seasonPeak

When the seasonal hazards worth planning around — the rainy season, tropical-cyclone risk and dust haze — are active through the year.

Theunissen's rainy season runs October–April, when most of the year's rain falls.

Rainy season
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Best time to visit Theunissen

TravelBeach/poolTemperatureCloudsPrecipitation

To characterize how pleasant the weather is in Theunissen throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.

Around early April, Theunissen is still near the start of its best-weather window — great conditions with the peak-season crowds not yet at full swing.

Inferred from the travel-score curve; month-by-month visitor numbers are a planned addition.

The travel score favors clear, rainless days with daytime highs between 18°C and 28°C. Based on this score, the best time of year to visit Theunissen for general outdoor tourist activities is from late March to mid October, with a peak score in the first week of September.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timetravel scoretemperaturecloudsprecipitationSep 3 · 8.9

The travel score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

Travel score (0–10)Rating
Jan4.9fair
Feb5.4fair
Mar6.6good
Apr7.7ideal
May8.2ideal
Jun7.9ideal
Jul8.0ideal
Aug8.5ideal
Sep8.5ideal
Oct7.2good
Nov6.1good
Dec5.1fair

The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, the best time of year to visit Theunissen for hot-weather activities is from late August to late April, with a peak score in the third week of September.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timebeach/pool scoretemperaturecloudsprecipitationSep 18 · 7.8

The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

What to pack for Theunissen, by month

EssentialRecommendedOptional

Month by month, what's worth putting in the bag — from the temperature range, rain chance, sun and wind. Tap a month for a quick packing note.

For a warm-season trip around January (highs near 30°C), the essentials are light clothes, rain gear and sun protection. In the cold season around June (highs near 18°C), pack a warm layer.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In January, Theunissen sees daytime highs around 30°C and nights near 17°C. Pack light clothes and sun protection. Worth having: rain gear. About 14 days see rain.

UV index (midday) in Theunissen by month

LowModerateHighVery highExtreme

Clear-sky midday UV index through the year, shaded by the WHO exposure levels — how much sun protection each month calls for.

Under clear skies, the midday UV index in Theunissen peaks around January 14 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 21 at about 5 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highHighModerateHighVery highExtremeJan 14UV 15Jun 21UV 5
UV index (midday)Level
Jan15Extreme
Feb13Extreme
Mar11Extreme
Apr8Very high
May6High
Jun5Moderate
Jul5Moderate
Aug7High
Sep9Very high
Oct11Extreme
Nov12Extreme
Dec14Extreme

Average hourly UV index in Theunissen

LowModerateHighVery highExtreme

Modeled clear-sky UV for every hour of every day — when in the day sun protection actually matters.

The whole year hour by hour: each column is a day, each row an hour, and the color is the modeled clear-sky UV index — the midday peak scaled down as the sun sits lower in the sky. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

UV falls off far faster than brightness as the sun drops, so even in January the burn window is concentrated in the middle of the day: about 9 hours a day reach index 3 (protection recommended), and 7 hours reach 6 or more. Mornings and late afternoons stay comparatively gentle year round.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM
UV ≥ 3 (h/day)UV ≥ 6 (h/day)
Jan97
Feb8.56.5
Mar7.55.5
Apr6.54
May50
Jun4.50
Jul4.50
Aug62.5
Sep74.5
Oct85.5
Nov96.5
Dec97

Air quality in Theunissen by month

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see which months the air is worst, not just the yearly average.

Air quality in Theunissen is worst in July — around 25 µg/m³ PM2.5 (moderate), about 3.7× the cleanest month (December, 7 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1025 µg/m³Dec 187 µg/m³
PM2.5 (µg/m³)Level
Jan8Good
Feb10Good
Mar13Moderate
Apr16Moderate
May21Moderate
Jun24Moderate
Jul25Moderate
Aug23Moderate
Sep22Moderate
Oct16Moderate
Nov8Good
Dec7Good
Almanac & agriculture

Growing season

Chance of a frost-free dayReliably frost-free (≥90%)

Theunissen is mild enough that a frost-free day stays more likely than not even in midwinter. Nights are reliably above freezing from about August 19 to May 26 (281 days); outside that window a hard frost is an occasional risk.

0%25%50%75%100%JanFebMarAprMayJunJulAugSepOctNovDecreliably frost-freereliably frost-freeAug 1990%May 2690%
Frost-free chance (%)Frost nights
Jan1000
Feb1000
Mar1000
Apr1000
May965
Jun7330
Jul6831
Aug8817
Sep990
Oct1000
Nov1000
Dec1000

Growing degree days

Degree days (base 10°C)Frost-free shaded

Growing degree days tally heat above 10°C: each day adds however many degrees its average temperature runs over that threshold, and cold days add nothing. Theunissen banks about 2,796 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around January.

01,0002,0003,000JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan419
Feb361
Mar342
Apr219
May106
Jun7
Jul4
Aug85
Sep213
Oct303
Nov339
Dec398

Solar energy

Average daily shortwave solar energy reaching the ground, banded into brightness zones so the number means something at a glance.

Solar energy is how much sunlight actually reaches the ground each day, measured in kilowatt-hours per square metre (kWh/m²) — the combined effect of how long the sun is up, how high it climbs, and how much cloud gets in the way. It's the raw fuel a solar panel has to work with: for scale, 1 kWh/m² a day is dim and wintry, while 7+ is desert-bright.

Theunissen receives about 5.8 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 3.6 and 7.6 kWh/m².

The brighter stretch of the year lasts 6.3 months, from around Sep 7 to Mar 16. The brightest month is December, averaging about 7.6 kWh/m² (intense).

The dimmest month is June, down near 3.7 kWh/m² — roughly 51% less than the December peak.

0123456789JanFebMarAprMayJunJulAugSepOctNovDecbrighterdimmerbrighterdimmoderatebrightintenseDec 207.6 kWhJun 193.6 kWh
Solar energy (kWh/m²)Level
Jan7.3Intense
Feb6.7Intense
Mar5.8Bright
Apr4.8Bright
May4.1Bright
Jun3.7Moderate
Jul4.0Moderate
Aug4.8Bright
Sep6.1Intense
Oct6.9Intense
Nov7.4Intense
Dec7.5Intense

Where is Theunissen?

Theunissen sits at 28.4°S, 26.7°E, 1,406 m above sea level, in South Africa. The nearest listed city is Winburg, 32 km away.

Topography around Theunissen

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Theunissen.

Within 3 km, the terrain around Theunissen has only modest variations in elevation — a maximum elevation change of 87 m around an average of 1,393 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 303 m; within 80 km, large variations in elevation — a maximum elevation change of 626 m.

The land around Theunissen is covered by grassland (69%) within 3 km, grassland (74%) and cropland (23%) within 16 km, and grassland (64%) and cropland (33%) within 80 km.

3 km
87 m
16 km
303 m
80 km
626 m
treesshrubsgrasslandcroplandartificial surfaceswater
Nearby: Winburg 32 km · Virginia 38 km · Winnie Mandela 40 km · Welkom 48 km · Bultfontein 56 km · Hennenman 58 km · Phomolong 58 km · Odendaalsrus 60 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
Christian 86%or other traditional African religions 5%nothing in particular 5%Muslim 2%

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 Theunissen (-28.411°, 26.7011°, elevation 1,406 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. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).