Aarau weather in April

In April, Aarau sees average daytime highs of 14°C and overnight lows near 5°C, with 100 mm of precipitation across 14.5 wet days and about 13.3 hours of daylight. It is the 6th-warmest and 9th-wettest month of the year here.

Highs climb over the month, from about 12°C in the first days to 16°C by the end. The sky is clear or mostly clear about 24% of the time in April, and the air most often feels dry.

Daylight stretches from about 12 h 30 min at the start of April to 14 h 06 min by month's end. Set against the rest of the year, April is Aarau's 6th-clearest and 5th-windiest month. For the whole year in context, see Aarau's year-round climate.

Daytime high: 14°; 6th warmest
Overnight low: 5°; 6th coldest
Precipitation: 100 mm; 14.5 wet days
Daylight: 13 h 24 min; 5:47 AM – 7:09 PM
Cloud cover: 65%; 6th clearest
Wind: 8 km/h; 5th windiest
Solar energy: 4.64 kWh/m²
Travel score: 3.5; out of 10

Aarau is capital of Canton Aargau, Switzerland.

Air quality: Good; PM2.5 8.9 µg/m³ · 2020
Density: 1,743/km²; people per km²
Founded: 1240

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

← March Aarau year-round climate May →Best places to visit in April

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

Temperature in April

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 12°C in the first days to 16°C by the end.

A typical April day in Aarau reaches about 14°C in the afternoon and slips back to 5°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between 7°C and 21°C. Set against its neighbours, April runs about 4°C warmer than March and about 4°C cooler than May.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Avg high (°C)	12	12	12	12	12	12	12	13	13	13	13	13	13	13	14	14	14	14	14	14	15	15	15	15	15	16	16	16	16	16
Avg low (°C)	3	3	3	3	3	3	4	4	4	4	4	4	4	4	4	4	5	5	5	5	5	6	6	6	6	6	7	7	7	7

	Avg high (°C)	Avg low (°C)
1	12	3
2	12	3
3	12	3
4	12	3
5	12	3
6	12	3
7	12	4
8	13	4
9	13	4
10	13	4
11	13	4
12	13	4
13	13	4
14	13	4
15	14	4
16	14	4
17	14	5
18	14	5
19	14	5
20	14	5
21	15	5
22	15	6
23	15	6
24	15	6
25	15	6
26	16	6
27	16	7
28	16	7
29	16	7
30	16	7

How April really feels in Aarau

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

heat index over the day's high

Days feeling ≤ 0°C

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.

Aarau weather by month

How April compares with the rest of the year at a glance. April is the 6th-warmest and 9th-wettest month here — the current month is highlighted below.

Month	High / Low (°C)	Rainfall (mm)	Wet days	Snow days	Daylight (hours)	Travel score
Jan	3° / -2°	97	13.4	7	8.7	0.0
Feb	5° / -1°	80	10.9	6.4	9.9	0.2
Mar	10° / 2°	97	14.2	4.4	11.6	1.9
Apr	14° / 5°	100	14.5	2.1	13.3	3.5
May	18° / 9°	148	17.3	0	14.9	4.7
Jun	21° / 12°	142	17.4	0	15.7	5.4
Jul	23° / 14°	152	17	0	15.3	5.9
Aug	23° / 13°	145	16.5	0	14.1	5.9
Sep	18° / 10°	108	13.2	0	12.4	5.3
Oct	13° / 6°	103	13.2	0.3	10.6	3.4
Nov	7° / 2°	100	13.1	3.3	9.1	0.9
Dec	4° / -1°	116	14.3	6.7	8.3	0.0

Cloud cover in April

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 24% of the time in April.

Beyond those clear spells, partly cloudy skies cover about 14% of April, with mostly cloudy or overcast conditions the remaining 63%.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Clearer (%)	39	39	39	39	40	40	39	40	40	40	40	40	40	40	39	39	39	39	37	37	36	36	34	34	33	33	32	31	31	31
Cloudier (%)	61	61	61	61	60	60	61	60	60	60	60	60	60	60	61	61	61	61	63	63	64	64	66	66	67	67	68	69	69	69

	Clearer (%)	Cloudier (%)
1	39	61
2	39	61
3	39	61
4	39	61
5	40	60
6	40	60
7	39	61
8	40	60
9	40	60
10	40	60
11	40	60
12	40	60
13	40	60
14	40	60
15	39	61
16	39	61
17	39	61
18	39	61
19	37	63
20	37	63
21	36	64
22	36	64
23	34	66
24	34	66
25	33	67
26	33	67
27	32	68
28	31	69
29	31	69
30	31	69

Chance of precipitation in April

Any precipitationSnow

Aarau gets around 100 mm of rain and snow over 14.5 wet days in April. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 49% and peaks near 56% on the wettest days, and about 2 days bring snow. The odds climb toward the end of the month.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Rain chance (%)	48	48	47	47	47	47	47	47	47	47	47	47	47	47	47	47	47	48	48	49	49	50	51	52	52	53	54	55	55	56
Snow chance (%)	10	10	10	9	9	9	9	9	9	9	9	9	9	8	8	8	8	7	7	7	6	6	5	5	4	4	3	3	2	2

	Rain chance (%)	Snow chance (%)
1	48	10
2	48	10
3	47	10
4	47	9
5	47	9
6	47	9
7	47	9
8	47	9
9	47	9
10	47	9
11	47	9
12	47	9
13	47	9
14	47	8
15	47	8
16	47	8
17	47	8
18	48	7
19	48	7
20	49	7
21	49	6
22	50	6
23	51	5
24	52	5
25	52	4
26	53	4
27	54	3
28	55	3
29	55	2
30	56	2

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 100% of days. It rarely turns muggy — the humid and sticky bands barely register.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Dry (%)	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	99
Comfortable (%)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	1

	Dry (%)	Comfortable (%)
1	100	0
2	100	0
3	100	0
4	100	0
5	100	0
6	100	0
7	100	0
8	100	0
9	100	0
10	100	0
11	100	0
12	100	0
13	100	0
14	100	0
15	100	0
16	100	0
17	100	0
18	100	0
19	100	0
20	100	0
21	100	0
22	100	0
23	100	0
24	100	0
25	100	0
26	100	0
27	100	0
28	100	0
29	100	0
30	99	1

Wind in April

Winds average 8 km/h in April.

Across April, daily wind ranges from about 7 km/h on the calmest days to 8 km/h at its breeziest. It stays fairly steady from day to day.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Wind speed (km/h)	8	8	8	8	8	8	8	8	8	8	8	8	8	8	8	8	8	8	8	8	8	8	7	7	7	7	7	7	7	7
Feels	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm

	Wind speed (km/h)	Feels
1	8	calm
2	8	calm
3	8	calm
4	8	calm
5	8	calm
6	8	calm
7	8	calm
8	8	calm
9	8	calm
10	8	calm
11	8	calm
12	8	calm
13	8	calm
14	8	calm
15	8	calm
16	8	calm
17	8	calm
18	8	calm
19	8	calm
20	8	calm
21	8	calm
22	8	calm
23	7	calm
24	7	calm
25	7	calm
26	7	calm
27	7	calm
28	7	calm
29	7	calm
30	7	calm

Sunrise & sunset in April

DaylightNight

Daylight runs from about 12 h 30 min at the start of April to 14 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 96 minutes over April. Sunrise moves from 6:17 AM to 5:21 AM, and sunset from 6:48 PM to 7:29 PM.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Daylight (h)	12.5	12.6	12.6	12.7	12.7	12.8	12.9	12.9	13.0	13.0	13.1	13.1	13.2	13.3	13.3	13.4	13.4	13.5	13.5	13.6	13.6	13.7	13.8	13.8	13.9	13.9	14.0	14.0	14.1	14.1
Sunrise (AM)	6:17	6:15	6:13	6:11	6:09	6:07	6:05	6:03	6:01	5:59	5:57	5:55	5:53	5:51	5:49	5:47	5:45	5:43	5:41	5:39	5:37	5:36	5:34	5:32	5:30	5:28	5:27	5:25	5:23	5:21
Sunset (PM)	6:48	6:49	6:51	6:52	6:54	6:55	6:56	6:58	6:59	7:01	7:02	7:03	7:05	7:06	7:08	7:09	7:11	7:12	7:13	7:15	7:16	7:18	7:19	7:21	7:22	7:23	7:25	7:26	7:28	7:29

	Daylight (h)	Sunrise (AM)	Sunset (PM)
1	12.5	6:17	6:48
2	12.6	6:15	6:49
3	12.6	6:13	6:51
4	12.7	6:11	6:52
5	12.7	6:09	6:54
6	12.8	6:07	6:55
7	12.9	6:05	6:56
8	12.9	6:03	6:58
9	13.0	6:01	6:59
10	13.0	5:59	7:01
11	13.1	5:57	7:02
12	13.1	5:55	7:03
13	13.2	5:53	7:05
14	13.3	5:51	7:06
15	13.3	5:49	7:08
16	13.4	5:47	7:09
17	13.4	5:45	7:11
18	13.5	5:43	7:12
19	13.5	5:41	7:13
20	13.6	5:39	7:15
21	13.6	5:37	7:16
22	13.7	5:36	7:18
23	13.8	5:34	7:19
24	13.8	5:32	7:21
25	13.9	5:30	7:22
26	13.9	5:28	7:23
27	14.0	5:27	7:25
28	14.0	5:25	7:26
29	14.1	5:23	7:28
30	14.1	5:21	7:29

Solar energy in April

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in April, about 4.64 kWh/m².

For context, solar energy here swings from a low near 1 kWh/m² to a high of 5.61 kWh/m² in June across the year — April's 4.64 kWh/m² falls in the middle.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Solar energy (kWh/m²)	4.1	4.1	4.2	4.2	4.3	4.3	4.3	4.4	4.4	4.5	4.5	4.6	4.6	4.6	4.7	4.7	4.7	4.8	4.8	4.8	4.8	4.8	4.8	4.8	4.8	4.8	4.8	4.8	4.8	4.8
Level	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright

	Solar energy (kWh/m²)	Level
1	4.1	Bright
2	4.1	Bright
3	4.2	Bright
4	4.2	Bright
5	4.3	Bright
6	4.3	Bright
7	4.3	Bright
8	4.4	Bright
9	4.4	Bright
10	4.5	Bright
11	4.5	Bright
12	4.6	Bright
13	4.6	Bright
14	4.6	Bright
15	4.7	Bright
16	4.7	Bright
17	4.7	Bright
18	4.8	Bright
19	4.8	Bright
20	4.8	Bright
21	4.8	Bright
22	4.8	Bright
23	4.8	Bright
24	4.8	Bright
25	4.8	Bright
26	4.8	Bright
27	4.8	Bright
28	4.8	Bright
29	4.8	Bright
30	4.8	Bright

Planning a trip in April

Is April a good time to visit Aarau?

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

3.5

Sightseeing

6th-best month of the year

0.1

Beach & pool

6th-best month of the year

April is a weaker month for outdoor sightseeing in Aarau.

What to pack for Aarau in April

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

In April, Aarau sees daytime highs around 14°C and nights near 5°C. Pack rain gear. Worth having: a warm layer and sun protection. About 15 days see rain.

rain geara warm layersun protection

UV index in Aarau in April

LowModerateHighVery highExtreme

Clear-sky midday UV in April peaks around 5 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Aarau peaks around July 15 at about 8 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near January 1 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
UV index (midday)	1	2	4	5	7	7	8	7	4	3	2	1
Level	Low	Moderate	Moderate	Moderate	High	Very high	Very high	High	Moderate	Moderate	Low	Low

	UV index (midday)	Level
Jan	1	Low
Feb	2	Moderate
Mar	4	Moderate
Apr	5	Moderate
May	7	High
Jun	7	Very high
Jul	8	Very high
Aug	7	High
Sep	4	Moderate
Oct	3	Moderate
Nov	2	Low
Dec	1	Low

Location & terrain

Where is Aarau?

Aarau sits at 47.4°N, 8.0°E, 389 m above sea level, in Switzerland. The nearest listed city is Olten, 12 km away.

Topography around Aarau

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

Within 3 km, the terrain around Aarau has only modest variations in elevation — a maximum elevation change of 198 m around an average of 416 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 695 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,987 m.

The land around Aarau is covered by trees (48%) and artificial surfaces (26%) within 3 km, trees (50%) and grassland (24%) within 16 km, and trees (47%) and grassland (28%) within 80 km.

3 km

198 m

trees 48%

16 km

695 m

trees 50%

80 km

2,987 m

trees 47%

treesgrasslandcroplandartificial surfacesbare terrainwater

← March Aarau year-round climate May →Best places to visit in April

April weather nearby: Olten 12 km · Bad Säckingen 19 km · Baden 22 km · Wettingen 23 km · Dietikon 27 km · Rheinfelden 27 km · Waldshut-Tiengen 29 km · Zürich (Kreis 9) 33 km

Switzerland travel facts

Travel advisory: Level 1; Exercise Normal Precautions
Power plugs: Type C / J; 230 V · 50 Hz
Prices: ≈ 112% of US; price level, 2025
GDP per capita: $114,769; 2025
Happiness: 7.0 / 10; World Happiness, 2025
Safe drinking water: 97%; of population, 2024
Homicide rate: 0.6; per 100k, 2023
Road deaths: 2.2; per 100k/yr, 2019
Income group: High; World Bank
English: High; EF EPI 564
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 Aarau (47.3925°, 8.0442°, elevation 389 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. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).

	Avg high (°C)	Avg low (°C)
1	12	3
2	12	3
3	12	3
4	12	3
5	12	3
6	12	3
7	12	4
8	13	4
9	13	4
10	13	4
11	13	4
12	13	4
13	13	4
14	13	4
15	14	4
16	14	4
17	14	5
18	14	5
19	14	5
20	14	5
21	15	5
22	15	6
23	15	6
24	15	6
25	15	6
26	16	6
27	16	7
28	16	7
29	16	7
30	16	7

	Clearer (%)	Cloudier (%)
1	39	61
2	39	61
3	39	61
4	39	61
5	40	60
6	40	60
7	39	61
8	40	60
9	40	60
10	40	60
11	40	60
12	40	60
13	40	60
14	40	60
15	39	61
16	39	61
17	39	61
18	39	61
19	37	63
20	37	63
21	36	64
22	36	64
23	34	66
24	34	66
25	33	67
26	33	67
27	32	68
28	31	69
29	31	69
30	31	69

	Rain chance (%)	Snow chance (%)
1	48	10
2	48	10
3	47	10
4	47	9
5	47	9
6	47	9
7	47	9
8	47	9
9	47	9
10	47	9
11	47	9
12	47	9
13	47	9
14	47	8
15	47	8
16	47	8
17	47	8
18	48	7
19	48	7
20	49	7
21	49	6
22	50	6
23	51	5
24	52	5
25	52	4
26	53	4
27	54	3
28	55	3
29	55	2
30	56	2

	Dry (%)	Comfortable (%)
1	100	0
2	100	0
3	100	0
4	100	0
5	100	0
6	100	0
7	100	0
8	100	0
9	100	0
10	100	0
11	100	0
12	100	0
13	100	0
14	100	0
15	100	0
16	100	0
17	100	0
18	100	0
19	100	0
20	100	0
21	100	0
22	100	0
23	100	0
24	100	0
25	100	0
26	100	0
27	100	0
28	100	0
29	100	0
30	99	1

	Avg high (°C)	Avg low (°C)
1	12	3
2	12	3
3	12	3
4	12	3
5	12	3
6	12	3
7	12	4
8	13	4
9	13	4
10	13	4
11	13	4
12	13	4
13	13	4
14	13	4
15	14	4
16	14	4
17	14	5
18	14	5
19	14	5
20	14	5
21	15	5
22	15	6
23	15	6
24	15	6
25	15	6
26	16	6
27	16	7
28	16	7
29	16	7
30	16	7

	Clearer (%)	Cloudier (%)
1	39	61
2	39	61
3	39	61
4	39	61
5	40	60
6	40	60
7	39	61
8	40	60
9	40	60
10	40	60
11	40	60
12	40	60
13	40	60
14	40	60
15	39	61
16	39	61
17	39	61
18	39	61
19	37	63
20	37	63
21	36	64
22	36	64
23	34	66
24	34	66
25	33	67
26	33	67
27	32	68
28	31	69
29	31	69
30	31	69

	Rain chance (%)	Snow chance (%)
1	48	10
2	48	10
3	47	10
4	47	9
5	47	9
6	47	9
7	47	9
8	47	9
9	47	9
10	47	9
11	47	9
12	47	9
13	47	9
14	47	8
15	47	8
16	47	8
17	47	8
18	48	7
19	48	7
20	49	7
21	49	6
22	50	6
23	51	5
24	52	5
25	52	4
26	53	4
27	54	3
28	55	3
29	55	2
30	56	2

	Dry (%)	Comfortable (%)
1	100	0
2	100	0
3	100	0
4	100	0
5	100	0
6	100	0
7	100	0
8	100	0
9	100	0
10	100	0
11	100	0
12	100	0
13	100	0
14	100	0
15	100	0
16	100	0
17	100	0
18	100	0
19	100	0
20	100	0
21	100	0
22	100	0
23	100	0
24	100	0
25	100	0
26	100	0
27	100	0
28	100	0
29	100	0
30	99	1

	Avg high (°C)	Avg low (°C)
1	12	3
2	12	3
3	12	3
4	12	3
5	12	3
6	12	3
7	12	4
8	13	4
9	13	4
10	13	4
11	13	4
12	13	4
13	13	4
14	13	4
15	14	4
16	14	4
17	14	5
18	14	5
19	14	5
20	14	5
21	15	5
22	15	6
23	15	6
24	15	6
25	15	6
26	16	6
27	16	7
28	16	7
29	16	7
30	16	7

	Clearer (%)	Cloudier (%)
1	39	61
2	39	61
3	39	61
4	39	61
5	40	60
6	40	60
7	39	61
8	40	60
9	40	60
10	40	60
11	40	60
12	40	60
13	40	60
14	40	60
15	39	61
16	39	61
17	39	61
18	39	61
19	37	63
20	37	63
21	36	64
22	36	64
23	34	66
24	34	66
25	33	67
26	33	67
27	32	68
28	31	69
29	31	69
30	31	69

	Rain chance (%)	Snow chance (%)
1	48	10
2	48	10
3	47	10
4	47	9
5	47	9
6	47	9
7	47	9
8	47	9
9	47	9
10	47	9
11	47	9
12	47	9
13	47	9
14	47	8
15	47	8
16	47	8
17	47	8
18	48	7
19	48	7
20	49	7
21	49	6
22	50	6
23	51	5
24	52	5
25	52	4
26	53	4
27	54	3
28	55	3
29	55	2
30	56	2

	Dry (%)	Comfortable (%)
1	100	0
2	100	0
3	100	0
4	100	0
5	100	0
6	100	0
7	100	0
8	100	0
9	100	0
10	100	0
11	100	0
12	100	0
13	100	0
14	100	0
15	100	0
16	100	0
17	100	0
18	100	0
19	100	0
20	100	0
21	100	0
22	100	0
23	100	0
24	100	0
25	100	0
26	100	0
27	100	0
28	100	0
29	100	0
30	99	1