The city is located at 580 meters (1,900 feet) above sea level, and is the capital of the smallest Italian region, Valle d'Aosta, located in the north-west of Italy, on the border with France and Switzerland.
All around, there are mountains that exceed 4,000 meters (13,100 ft): to the south, the Gran Paradiso massif, to the north-west, the Mont Blanc, the highest peak in Europe (on the border with France), and to the north, the Grand Combin (in Switzerland) and the Matterhorn (on the border with Switzerland).
of the coldest month (December) is of 1.5 °C (34.7 °F), that of the warmest month (July) is of 22 °C (72 °F).
amounts to 550 millimeters (21.5 inches) per year. Due to its position in a valley arranged from west to east and surrounded by high mountains (as also happens in the city of Sion in Switzerland), the city does not receive much rainfall. However, from time to time, there may be more abundant rains than usual. In October 2000, when there were floods in north-western Italy, almost 300 mm (12 in) of rain fell.
is cold. There may be relatively mild periods, when Atlantic currents prevail, and other colder periods, when the temperature drops below freezing.
Although the winter is a fairly dry season, so snowfalls are not very frequent, they can sometimes be abundant.
In this season, cold air stagnates in the valley, especially when the wind is weak or absent. In December, when the sun is lower, it stays behind the mountains for a few hours, and this favors thermal inversion. In December 1990, after a not very intense cold spell, with snow on the ground and clear skies, the temperature dropped to -18 °C (-0.5 °F), with a maximum of -8 °C (17.5 °F), but at 1 pm it was still -12 °C (10.5 °F). However, the mountains to the north protect Aosta from cold waves, so the temperature almost never drops below -15 °C (5 °F).
Actually, the north-westerly wind that descends from the mountains, the föhn, can bring strong increases in temperature, which can reach 20 °C (68 °F) even in the middle of winter. In January 2007, it reached 23 °C (73.5 °F), with a minimum of 14 °C (57 °F).
in Aosta is quite hot, with many sunny days, and possible thunderstorms in the afternoon or evening. Nights are usually cool.
Sometimes there can be short, very hot periods, in which highs can reach 35 °C (95 °F). In late June 2019, during a short heatwave of African origin, the temperature reached 40.4 °C (104.7 °F).
to visit Aosta runs from mid-May to mid-September, since it is the warmest and sunniest period of the year. Sometimes, it can be hot in July and August, while in other circumstances, nights can be cool or even a little cold even in these months, so it can be useful to bring a sweatshirt or sweater and a light jacket for the evening.
. Here are the average temperatures.
January is generally a cold month. The average temperature is of
1.5 °C, with a minimum of
-3.2 °C and a maximum of
6.2 °C.
On the coldest nights of the month, the temperature usually drops to around
-9.5 °C. However, it dropped to
-17.6 °C in January 2006.
On the warmest days of the month, the temperature usually reaches around
15 °C. However, it reached
22.6 °C in January 2007.
Precipitation amounts to
40 mm, distributed over 6 days.
The day lasts on average 9 hours and 5 minutes.
The average humidity is 70%.
The average wind speed is of
14 kph.
February is generally a quite cold month. The average temperature is of
4.2 °C, with a minimum of
-1.7 °C and a maximum of
10 °C.
On the coldest nights of the month, the temperature usually drops to around
-8 °C. However, it dropped to
-16.5 °C in February 2010.
On the warmest days of the month, the temperature usually reaches around
18.5 °C. However, it reached
26 °C in February 2020.
Precipitation amounts to
25 mm, distributed over 4 days.
The day lasts on average 10 hours and 25 minutes.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is of
14 kph.
March is generally a quite mild month. The average temperature is of
8.4 °C, with a minimum of
2.2 °C and a maximum of
14.6 °C.
On the coldest nights of the month, the temperature usually drops to around
-3 °C. However, it dropped to
-8.7 °C in March 2006.
On the warmest days of the month, the temperature usually reaches around
23.5 °C. However, it reached
26.3 °C in March 2020.
Precipitation amounts to
30 mm, distributed over 4 days.
The day lasts on average 12 hours and 0 minutes.
The average humidity is 70%.
The average wind speed is of
14 kph.
April is generally a mild month. The average temperature is of
11.7 °C, with a minimum of
5.3 °C and a maximum of
18.1 °C.
On the coldest nights of the month, the temperature usually drops to around
-0.5 °C. However, it dropped to
-4.6 °C in April 2017.
On the warmest days of the month, the temperature usually reaches around
25 °C. However, it reached
29.5 °C in April 2007.
Precipitation amounts to
50 mm, distributed over 6 days.
The day lasts on average 13 hours and 35 minutes.
The average humidity is 74%. Hence, the air is normally humid.
The average wind speed is of
13 kph.
May is generally a very mild month. The average temperature is of
15.6 °C, with a minimum of
9.7 °C and a maximum of
21.5 °C.
On the coldest nights of the month, the temperature usually drops to around
5 °C. However, it dropped to
-0.7 °C in May 2019.
On the warmest days of the month, the temperature usually reaches around
28.5 °C. However, it reached
32.2 °C in May 2007.
Precipitation amounts to
70 mm, distributed over 8 days.
The day lasts on average 15 hours and 0 minutes. So the days are long.
The average humidity is 76%. Hence, the air is normally humid.
The average wind speed is of
12 kph.
June is generally a warm month. The average temperature is of
19.2 °C, with a minimum of
13.3 °C and a maximum of
25.1 °C.
On the coldest nights of the month, the temperature usually drops to around
8.5 °C. However, it dropped to
2.6 °C in June 2011.
On the warmest days of the month, the temperature usually reaches around
32.5 °C. However, it reached
40.4 °C in June 2019.
Precipitation amounts to
45 mm, distributed over 7 days.
The day lasts on average 15 hours and 40 minutes. So the days are long. June 21, the summer solstice, is the longest day of the year in the Northern Hemisphere.
The average humidity is 74%. Hence, the air is normally humid.
The average wind speed is of
10 kph.
July, the warmest month of the year, is generally a warm month. However, there are remarkable differences between night and day. The average temperature is of
22.2 °C, with a minimum of
15.5 °C and a maximum of
28.8 °C.
On the coldest nights of the month, the temperature usually drops to around
10.5 °C. However, it dropped to
6.1 °C in July 2007.
On the warmest days of the month, the temperature usually reaches around
33.5 °C. However, it reached
36.5 °C in July 2020.
Precipitation amounts to
35 mm, distributed over 6 days.
The day lasts on average 15 hours and 20 minutes. So the days are long.
The average humidity is 72%. Hence, the air is normally humid.
The average wind speed is of
10 kph.
August is generally a warm month. However, there are remarkable differences between night and day. The average temperature is of
21.5 °C, with a minimum of
14.9 °C and a maximum of
28.1 °C.
On the coldest nights of the month, the temperature usually drops to around
9.5 °C. However, it dropped to
3.6 °C in August 2006.
On the warmest days of the month, the temperature usually reaches around
33.5 °C. However, it reached
38 °C in August 2020.
Precipitation amounts to
40 mm, distributed over 7 days.
The day lasts on average 14 hours and 0 minutes.
The average humidity is 74%. Hence, the air is normally humid.
The average wind speed is of
9 kph.
September is generally a very mild month. The average temperature is of
17.4 °C, with a minimum of
11.7 °C and a maximum of
23.1 °C.
On the coldest nights of the month, the temperature usually drops to around
4.5 °C. However, it dropped to
-0.5 °C in September 2010.
On the warmest days of the month, the temperature usually reaches around
29 °C. However, it reached
34 °C in September 2019.
Precipitation amounts to
45 mm, distributed over 5 days.
The day lasts on average 12 hours and 30 minutes.
The average humidity is 76%. Hence, the air is normally humid.
The average wind speed is of
10 kph.
October is generally a mild month. The average temperature is of
12.2 °C, with a minimum of
6.8 °C and a maximum of
17.6 °C.
On the coldest nights of the month, the temperature usually drops to around
0.5 °C. However, it dropped to
-6.3 °C in October 2007.
On the warmest days of the month, the temperature usually reaches around
24 °C. However, it reached
30.7 °C in October 1997.
Precipitation amounts to
55 mm, distributed over 6 days.
The day lasts on average 10 hours and 55 minutes.
The average humidity is 77%. Hence, the air is normally humid.
The average wind speed is of
11 kph.
November is generally a quite cold month. The average temperature is of
6.4 °C, with a minimum of
1.4 °C and a maximum of
11.5 °C.
On the coldest nights of the month, the temperature usually drops to around
-4.5 °C. However, it dropped to
-14.1 °C in November 2008.
On the warmest days of the month, the temperature usually reaches around
20 °C. However, it reached
23 °C in November 2015.
Precipitation amounts to
75 mm, distributed over 7 days.
The day lasts on average 9 hours and 25 minutes.
The average humidity is 74%. Hence, the air is normally humid.
The average wind speed is of
13 kph.
December, the coldest month of the year, is generally a cold month. The average temperature is of
0.8 °C, with a minimum of
-3.4 °C and a maximum of
5.1 °C.
On the coldest nights of the month, the temperature usually drops to around
-8 °C. However, it dropped to
-18.9 °C in December 2010.
On the warmest days of the month, the temperature usually reaches around
17 °C. However, it reached
21.7 °C in December 1994.
Precipitation amounts to
45 mm, distributed over 6 days.
The day lasts on average 8 hours and 40 minutes. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.
The average humidity is 70%.
The average wind speed is of
14 kph.