Heidelberg weather in April

In April, Heidelberg sees average daytime highs of 23°C and overnight lows near 11°C, with 41 mm of rain across 6.8 wet days and about 11.4 hours of daylight. It is the 8th-warmest and 7th-wettest month of the year here.

Highs ease over the month, from about 23°C in the first days to 22°C by the end. The sky is clear or mostly clear about 57% of the time in April, and the air most often feels dry.

Daylight stretches from about 11 h 48 min at the start of April to 11 hours by month's end. Set against the rest of the year, April is Heidelberg's 6th-clearest and 11th-windiest month. For the whole year in context, see Heidelberg's year-round climate.

Daytime high
23°
8th warmest
Overnight low
11°
6th coldest
Rainfall
41 mm
6.8 wet days
Daylight
11 h 24 min
6:26 AM – 5:48 PM
Cloud cover
39%
6th clearest
Wind
9 km/h
11th windiest
Solar energy
4.81 kWh/m²
Travel score
7.6
out of 10

Heidelberg is town in Gauteng province, South Africa.

Founded
1886

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

Temperature in April

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 23°C in the first days to 22°C by the end.

A typical April day in Heidelberg reaches about 23°C in the afternoon and slips back to 11°C overnight — a 12°C spread between the day's warmth and the night's chill. On most days the high lands between 19°C and 26°C. Set against its neighbours, April runs about 2°C cooler than March and about 2°C warmer than May.

10°15°20°25°30°151015202530
Avg high (°C)Avg low (°C)
12413
22413
32412
42312
52312
62312
72312
82312
92312
102312
112311
122311
132311
142311
152311
162311
172311
182311
192210
202210
212210
222210
232210
242210
252210
262210
272210
28229
29229
30229

How April really feels in Heidelberg

Once humidity and wind are folded in, April averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

April sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Heidelberg weather by month

How April compares with the rest of the year at a glance. April is the 8th-warmest and 7th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan26° / 16°1291613.55.9
Feb26° / 16°10012.812.96.2
Mar25° / 14°8411.512.26.9
Apr23° / 11°416.811.47.6
May21° / 152.710.78.2
Jun18° / 71.510.48.0
Jul18° / 30.710.58.1
Aug21° / 112.111.18.6
Sep25° / 10°223.611.88.5
Oct26° / 13°7810.512.67.0
Nov26° / 14°10113.813.36.2
Dec26° / 15°1401713.65.7

Cloud cover in April

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 57% of the time in April.

Beyond those clear spells, partly cloudy skies cover about 18% of April, with mostly cloudy or overcast conditions the remaining 25%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
16931
26931
36931
47030
57030
67030
77129
87129
97228
107228
117327
127327
137525
147525
157624
167624
177723
187723
197723
207822
217822
227822
237822
247921
257921
267921
278020
288119
298218
308218

Chance of precipitation in April

Any precipitation

Heidelberg gets around 41 mm of rain over 6.8 wet days in April. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 23% and peaks near 30% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%40%151015202530
Rain chance (%)
130
229
329
428
528
627
726
826
925
1025
1124
1224
1324
1424
1523
1623
1723
1822
1922
2021
2121
2221
2320
2420
2520
2619
2718
2817
2917
3016

Humidity in April

DryComfortableHumidMuggyOppressiveMiserable

Most of April feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, April lands in the dry band about 91% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)
174242
276222
378202
479192
582171
683161
784151
886131
988120
1089110
1190100
129190
139280
149370
159460
169550
179550
189640
199640
209730
219730
229820
239820
249820
259820
269910
279910
289910
299910
309910

Wind in April

Winds average 9 km/h in April.

Across April, daily wind ranges from about 9 km/h on the calmest days to 10 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (km/h)Feels
19calm
29calm
39calm
49calm
59calm
69calm
79calm
89calm
99calm
109calm
119calm
129calm
139calm
149calm
159calm
169calm
179calm
189calm
199calm
209calm
219calm
229calm
239calm
249calm
2510calm
2610calm
2710calm
2810calm
2910calm
3010calm

Sunrise & sunset in April

DaylightNight

Daylight runs from about 11 h 48 min at the start of April to 11 hours by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 48 minutes over April. Sunrise moves from 6:18 AM to 6:33 AM, and sunset from 6:04 PM to 5:35 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
111.86:186:04
211.76:196:03
311.76:196:02
411.76:206:01
511.76:206:00
611.66:215:59
711.66:215:58
811.66:225:56
911.66:225:55
1011.56:235:54
1111.56:235:53
1211.56:245:52
1311.56:245:51
1411.46:255:50
1511.46:255:49
1611.46:265:48
1711.36:265:47
1811.36:275:46
1911.36:275:45
2011.36:285:44
2111.26:285:43
2211.26:295:42
2311.26:295:41
2411.26:305:40
2511.26:305:39
2611.16:315:38
2711.16:315:38
2811.16:325:37
2911.16:325:36
3011.06:335:35

Solar energy in April

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in April, about 4.81 kWh/m².

For context, solar energy here swings from a low near 3.89 kWh/m² to a high of 6.84 kWh/m² in December across the year — April's 4.81 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.1Bright
25.1Bright
35.0Bright
45.0Bright
55.0Bright
65.0Bright
75.0Bright
85.0Bright
95.0Bright
104.9Bright
114.9Bright
124.9Bright
134.9Bright
144.8Bright
154.8Bright
164.8Bright
174.8Bright
184.8Bright
194.7Bright
204.7Bright
214.7Bright
224.7Bright
234.7Bright
244.6Bright
254.6Bright
264.6Bright
274.6Bright
284.5Bright
294.5Bright
304.5Bright
Planning a trip in April

Hazard calendar for Heidelberg

In seasonPeak

None of Heidelberg's seasonal hazards are active in April. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.

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

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

Is April a good time to visit Heidelberg?

Our two travel scores rate April for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

7.6
Sightseeing
6th-best month of the year
5.7
Beach & pool
7th-best month of the year

April is one of the better times to visit Heidelberg for general sightseeing.

What to pack for Heidelberg in April

From April's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In April, Heidelberg sees daytime highs around 23°C and nights near 11°C. Worth packing: light clothes and sun protection. About 7 days see rain.

light clothessun protection

UV index in Heidelberg in April

LowModerateHighVery highExtreme

Clear-sky midday UV in April peaks 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 Heidelberg peaks around January 12 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 20 at about 5 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highHighVery highExtremeJan 12UV 14Jun 20UV 5
UV index (midday)Level
Jan14Extreme
Feb13Extreme
Mar12Extreme
Apr9Very high
May6High
Jun5High
Jul6High
Aug7Very high
Sep9Very high
Oct10Extreme
Nov12Extreme
Dec14Extreme

Air quality in Heidelberg in April

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where April falls, not just the annual average.

Air quality in Heidelberg is worst in June — around 259 µg/m³ PM2.5 (very unhealthy), about 6.0× the cleanest month (January, 43 µg/m³).

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

0306090120150180210240270JanFebMarAprMayJunJulAugSepOctNovDecPoorUnhealthyVery unhealthyUnhealthyPoorJun 23259 µg/m³Jan 1344 µg/m³
PM2.5 (µg/m³)Level
Jan43Poor
Feb63Unhealthy
Mar101Unhealthy
Apr158Very unhealthy
May232Very unhealthy
Jun259Very unhealthy
Jul259Very unhealthy
Aug200Very unhealthy
Sep144Unhealthy
Oct91Unhealthy
Nov65Unhealthy
Dec50Poor
Location & terrain

Where is Heidelberg?

Heidelberg sits at 26.5°S, 28.4°E, 1,525 m above sea level, in South Africa. The nearest listed city is Nigel, 14 km away.

Topography around Heidelberg

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

Within 3 km, the terrain around Heidelberg has only modest variations in elevation — a maximum elevation change of 239 m around an average of 1,557 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 440 m; within 80 km, large variations in elevation — a maximum elevation change of 665 m.

The land around Heidelberg is covered by grassland (51%) and artificial surfaces (28%) within 3 km, grassland (60%) and cropland (30%) within 16 km, and grassland (50%) and cropland (34%) within 80 km.

3 km
239 m
16 km
440 m
80 km
665 m
treesshrubsgrasslandcroplandartificial surfacesbare terrainwater
April weather nearby: Nigel 14 km · Tokoza 28 km · Springs 29 km · Balfour 29 km · Brakpan 30 km · Boksburg 34 km · Germiston 35 km · Alberton 35 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 Heidelberg (-26.5048°, 28.3592°, elevation 1,525 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).