Climate and monthly weather forecast
Aarau, Switzerland

englishespañol中文
Share

The climate of Aarau

Aarau, nestled in the heart of Switzerland, is characterized by a Marine West Coast climate, warm summer, and officially classified by the Köppen climate classification as Cfb. This classification is predominantly due to the uniquely temperate weather conditions typically observed in this region throughout the year.

Examining the temperature trends over the twelve months, the average highs range from 2.9°C (37.2°F) in the winter month of January to 23.3°C (73.9°F) in the summer months of July and August. On the other hand, the average low swings between a chilling -3.3°C (26.1°F) in January to a relatively comfortable 11.8°C (53.2°F) in July and August. This diverse temperature spread reflects the region's distinctive blend of weather nuances across different seasons.

Of great significance in Aarau’s climate is its balanced distribution of rainfall. Throughout the year, the rain gauge records quantities varying from 45mm (1.77") in September to 106mm (4.17") in May. May also marks the month with the highest number of rainy days, counting up to 22.4 days. December sees the highest snowfall, with 143mm (5.63") recorded, while June, July, August, and September remain virtually snow-free.

Furthermore, the daylight varies from a minimum of 8.6 hours in December to a maximum of 15.9 hours in June, demonstrating the typical contrast between shorter winter days and extended summer daylight. The uncertainty and fluctuation in this weather pattern, coupled with the intriguing natural beauty of Switzerland, unarguably contribute to the peculiar charm of Aarau.

The best time to visit Aarau

The optimal time for a visit to Aarau falls in the summer months of June to August, with temperatures reaching a pleasant 21.2°C (70.2°F) to 23.3°C (73.9°F) on average. This period also presents an opportunity to bask in the generous daylight, reaching a high of 15.9 hours in June. The rainfall in summer averages around 100mm (3.94") to 105mm (4.13"), which contributes to the overall refreshing ambiance of the region.

The worst time to visit Aarau

Taking into account the various climatic conditions, it appears that the winter months of December through February may not be the best time for a visit. During this period, temperatures frequently drop below freezing, and the amount of daylight is at its yearly minimum, peaking only at 9 hours in February. Besides, substantial snowfall occurs during these months, which may hinder mobility for certain visitors.

Spring weather in Aarau

In Aarau, spring spans from March to May, bringing about a gentle rise in temperature from 9°C (48.2°F) in March to 17.3°C (63.1°F) in May. Notably, May also has the highest rainfall at 106mm (4.17") with an average of 22.4 rainy days. Daylight steadily increases from 11.9 hours in March to a generous 15.1 hours in May, while the sunshine hours peak at 9.1 in May, contributing to the overall pleasant spring ambiance.

Summer weather in Aarau

Summer in Aarau, from June to August, is marked by warm temperatures averaging between 21.2°C (70.2°F) and 23.3°C (73.9°F). Rainfall is moderate, ranging from 100mm (3.94") in July to 105mm (4.13") in June. The area becomes devoid of snowfall, and daylight reaches 15.9 hours in June, progressively reducing to 14.2 hours in August. Sunshine hours also peak during this season, ranging from 10.3 hours in July to 10.4 hours in August.

Autumn weather in Aarau

Autumn in Aarau sets in from September to November. The season is signified by reducing temperatures from 18.8°C (65.8°F) in September to 8.3°C (46.9°F) by November. Daylight hours also reduce from 12.6 in September to 9.4 hours in November. Precipitation is moderate, with rainfall ranging from 45mm (1.77") in September to 60mm (2.36") in November, marking an overall cooler and wetter season.

Winter weather in Aarau

Winter in Aarau, beginning in December and ending in February, demonstrates a palpable drop in temperatures with averages falling between -3.3°C (26.1°F) and 3.8°C (38.8°F). Snowfall is abundant, peaking at 143mm (5.63") in December. The daylight lasts for about 9 hours, and the sunshine hours diminish to their lowest at 5 hours. Consequently, these conditions paint a compelling picture of a typical Swiss winter.

Weather in January

The beginning of the year in Aarau, Switzerland, sees chilly temperatures and snowfall. January experiences the coldest weather with minimum temperatures dipping to -3.3°C (26.1°F) amid the winter season. With shorter daylight hours, locals often enjoy cozy indoors while slight window frost gives a picturesque feel to the Swiss cityscape. Weather in January »

Weather in February

Though February sustains the winter's chill, Aarau experiences a gradual creep in temperature from this month. Witnessing maximum snowfall of 153mm (6.02"), Aarau adorns a fresh white cloak. Winters continue to assert their dominance, however, February introduces a slightly longer daylight offering delightful afternoons. Weather in February »

Weather in March

Spring knocks the doors of Aarau in March, bringing with it warmer days and blooming landscapes. The shift from winter chill to spring warmth becomes pretty evident in Aarau during this time. The receding snowfall clears the way for blossoming flora, revealing the grassy terrains underneath the pristine white cover. Weather in March »

Weather in April

April, in Aarau, is marked by spring in full bloom accompanied by extended daylight hours. It is a pleasant shift from the chilling weather of the first quarter of the year. With snow almost entirely disappeared, outdoor activities gain momentum. Weather in April »

Weather in May

May brings the scent of blossoms and the melody of birdsong to Aarau. With the increase in sunshine hours, day activities serve as excellent recreations. The first month of summer, May displays an impressive temperature high of 17.3°C (63.1°F). Weather in May »

Weather in June

June unfurls the season of summer in all its glory in Aarau, making it a favored month for tourists. The weather is warmer, and the city looks breathtaking under the sharp summer sunlight. Outdoor enthusiasts can make the most of this weather due to longer daylight hours. Weather in June »

Weather in July

July becomes synonymous with warm sunlit days and cool summer nights in Aarau. The pleasant weather makes it a perfect canvas for travelers to paint their summer trips. As the weather heats up to 23.3°C (73.9°F), people engage in various outdoor activities. Weather in July »

Weather in August

Aarau, in August, basks in the charm of late summer. With temperatures aligning to 23.3°C (73.9°F) yet again, warmth wraps the city comfortably. August comes with abundant sunshine, inviting locals and visitors to enjoy outdoor recreational pursuits. Weather in August »

Weather in September

September marks the arrival of autumn in Aarau, signaling a transition from warm to mild weather. The summer's heat begins to fade, making way for comfortable temperature and occasional showers. The transformation from lush green to hues of orange and yellow unfolds a unique spectacle. Weather in September »

Weather in October

October paints Aarau in vibrant hues of fall and progressively cooler temperatures. It brings a decreased daylight duration, hinting towards the arrival of winter. The weather is pleasingly cool, prompting locals and tourists to revel in outdoor activities. Weather in October »

Weather in November

Aarau in November presents the departure of the fall and the arrival of early winter. The city wraps itself in a full-fledged winter coat with an average temperature diving down to 8.3°C (46.9°F). The days grow shorter and colder while nights witness an increase in chill. Weather in November »

Weather in December

Finally, December arrives in Aarau marking the zenith of the cold winter season. Featuring the year's heaviest rainfall of 81mm (3.19"), it gears up for the festive spirit. With daylight receding to its shortest duration, afternoons get clouded by early dusk. Weather in December »
[Resources]

Frequently asked questions

What part of the year is the coldest in Aarau?

January is the coldest month in Aarau, with the temperature often reaching an average high of 2.9°C (37.2°F) and an average low of -3.3°C (26.1°F).

What is the most humid month in Aarau?

With an average relative humidity of 88%, January is the most humid month.

How much does it rain in Aarau?

In Aarau, during the entire year, the rain falls for 190.8 days and collects up to 880mm (34.65") of precipitation.

When does it snow in Aarau?

January through May, October through December are months with snowfall in Aarau.

How much does it snow in Aarau?

In Aarau, Switzerland, during the entire year, snow falls for 39.9 days and aggregates up to 652mm (25.67") of snow.

When is the lowest UV index in Aarau?

January, February, October through December, with an average maximum UV index of 2, are months with the lowest UV index.

When does it snow the most in Aarau?

The month with the most snowfall in Aarau is February, when snow falls for 9.7 days and typically aggregates up to 153mm (6.02") of snow.

What is the least humid month in Aarau?

The months with the lowest humidity in Aarau are April and July, with an average relative humidity of 78%.

What is the rainiest month in Aarau?

May is the month with the most rainfall in Aarau, Switzerland. Rain falls for 22.4 days and accumulates 106mm (4.17") of precipitation.

When it does not snow in Aarau?

In Aarau, snow does not fall in June through September.

When are the longest days in Aarau?

With an average of 15h and 54min of daylight, June has the longest days of the year in Aarau, Switzerland.

What is the month with the highest UV index in Aarau?

June and July, with an average maximum UV index of 5, are months with the highest UV index.

What part of the year is the hottest in Aarau?

Aarau witnesses its peak temperatures during July and August, when the average high-temperature reaches 23.3°C (73.9°F).

What month has the most sunshine in Aarau?

With an average of 10.4h of sunshine, August has the most sunshine of the year.

What is the driest month in Aarau?

September is the month with the least rainfall. Rain falls for 14.5 days and accumulates 45mm (1.77") of precipitation.

When is Daylight Saving Time (DST) in Aarau?

On Sunday, 27. October 2024, at 03:00, Daylight Saving Time ends in Aarau, and the time zone changes from CEST to CET. The next Daylight Saving Time starts on Sunday, 30. March 2025, at 02:00, and the time zone reverts from CET to CEST.

What is the month with the shortest days in Aarau?

With an average of 8h and 30min of daylight, December has the shortest days of the year.

What is the month with the least sunshine in Aarau?

With an average of 5h of sunshine, December has the least sunshine of the year.

Average temperature
Aarau, Switzerland

Average temperature - Aarau, Switzerland

The warmest months (with the highest average high temperature) are July and August (23.3°C).
The month with the lowest average high temperature is January (2.9°C).

The months with the highest average low temperature are July and August (11.8°C).
The coldest month (with the lowest average low temperature) is February (-3.4°C).

[Resources]

Average pressure
Aarau, Switzerland

Average pressure - Aarau, Switzerland

The month with the highest atmospheric pressure is December (1020.9mbar).
The month with the lowest atmospheric pressure is April (1015.6mbar).

[Resources]

Average wind speed
Aarau, Switzerland

Average wind speed - Aarau, Switzerland

The windiest month (with the highest average wind speed) is March (8.8km/h).
The calmest month (with the lowest average wind speed) is August (5.9km/h).

[Resources]

Average humidity
Aarau, Switzerland

Average humidity - Aarau, Switzerland

The month with the highest relative humidity is January (88%).
The months with the lowest relative humidity are April and July (78%).

[Resources]

Average rainfall
Aarau, Switzerland

Average rainfall - Aarau, Switzerland

The wettest month (with the highest rainfall) is May (106mm).
The driest month (with the least rainfall) is September (45mm).

[Resources]

Average rainfall days
Aarau, Switzerland

Average rainfall days - Aarau, Switzerland

The month with the highest number of rainy days is May (22.4 days).
The month with the least rainy days is February (10.6 days).

[Resources]

Average snowfall
Aarau, Switzerland

Average snowfall - Aarau, Switzerland

The month with the highest snowfall is February (153mm).
The months with the least snowfall are June, July, August and September (0mm).

[Resources]

Average snowfall days
Aarau, Switzerland

Average snowfall days - Aarau, Switzerland

The month with the highest number of snowfall days is February (9.7 days).
The months with the least snowfall days are June, July, August and September (0 days).

[Resources]

Average daylight / Average sunshine
Aarau, Switzerland

Average daylight / Average sunshine - Aarau, Switzerland

The month with the longest days is June (Average daylight: 15h and 54min).
The month with the shortest days is December (Average daylight: 8h and 30min).

The month with the most sunshine is August (Average sunshine: 10h and 24min).
The month with the least sunshine is December (Average sunshine: 5h and 0min).

[Resources]

Average sunshine days
Aarau, Switzerland

Average sunshine days - Aarau, Switzerland

The month with the most sunshine days is October (15 days).
The month with the least sunshine days is May (6.6 days).

[Resources]

Average UV index
Aarau, Switzerland

Average UV index - Aarau, Switzerland

The months with the highest UV index are June and July (UV index 5).
The months with the lowest UV index are January, February, October, November and December (UV index 2).

[Resources]

Average visibility
Aarau, Switzerland

Average visibility - Aarau, Switzerland

The months with the highest visibility are March, April, July and August (9km).
The months with the lowest visibility are January, February, May, June, September, October, November and December (8km).

[Resources]

Aarau, Switzerland

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location