The city is located in central Italy, in the north-west of the Lazio region, 325 meters (1,065 feet) above sea level and about 40 km (25 mi) away from the coast of the Tyrrhenian Sea. In the vicinity of the city is
, located at an altitude of 510 meters (1,675 ft). About 15 km (9 mi) to the north-west is
, from December to February, is quite mild, however, it depends on the period.
There are mild periods, in which the Atlantic currents prevail, during which there can also be rainy days.
, which can be strong and can increase the feeling of cold. When the north wind blows, the temperature can remain close to freezing even during the day.
in Viterbo is more frequent than in Rome. In past decades, an average of 20 cm (8 in) of snow fell per year.
During cold waves, the temperature can drop several degrees below freezing. Typically, the temperature drops to -8/-10 °C (14/18 °F) in the coldest periods, however, in January 1985 it dropped to -12.7 °C (9.1 °F).
, from June to August, is hot and sunny, with rare rainy days and some thunderstorms coming from the Apennines.
Generally, the humidity is not high and the air becomes cool at night, however, there can also be very hot periods, with highs of 37/38 °C (99/100 °F). The heat record is 40 °C (104 °F), set on a few occasions (late June 2022, late July 2005, early August 2017).
to visit Viterbo are spring and autumn, ie from mid-April to mid-June and from September to early October. In June, the weather is often nice, but it can sometimes get hot, especially in the second half of the month.
. Here are the average temperatures.
January, the coldest month of the year, is generally a quite cold month. The average temperature is of
6.3 °C, with a minimum of
2.4 °C and a maximum of
10.2 °C.
On the coldest nights of the month, the temperature usually drops to around
-3.5 °C. However, it dropped to
-7.2 °C in January 2017.
On the warmest days of the month, the temperature usually reaches around
15.5 °C. However, it reached
19.3 °C in January 2018.
Precipitation amounts to
80 mm, distributed over 7 days.
The day lasts on average 9 hours and 30 minutes.
There are on average 4.5 hours of sunshine per day. So, the sun shines 45% of the time.
The average humidity is 75%. Hence, the air is normally humid.
The average wind speed is of
15.8 kph.
February is generally a quite mild month. The average temperature is of
7.1 °C, with a minimum of
2.6 °C and a maximum of
11.5 °C.
On the coldest nights of the month, the temperature usually drops to around
-3 °C. However, it dropped to
-10 °C in February 1991.
On the warmest days of the month, the temperature usually reaches around
17 °C. However, it reached
21 °C in February 2007.
Precipitation amounts to
70 mm, distributed over 7 days.
The day lasts on average 10 hours and 35 minutes.
There are on average 5 hours of sunshine per day. So, the sun shines 45% of the time.
The average humidity is 70%.
The average wind speed is of
16 kph.
March is generally a mild month. The average temperature is of
9.4 °C, with a minimum of
4.4 °C and a maximum of
14.3 °C.
On the coldest nights of the month, the temperature usually drops to around
-1 °C. However, it dropped to
-6.6 °C in March 2005.
On the warmest days of the month, the temperature usually reaches around
20.5 °C. However, it reached
26.5 °C in March 1991.
Precipitation amounts to
70 mm, distributed over 7 days.
The day lasts on average 12 hours and 0 minutes.
There are on average 5.5 hours of sunshine per day. So, the sun shines 47% of the time.
The average humidity is 68%.
The average wind speed is of
16.5 kph.
April is generally a mild month. The average temperature is of
12.3 °C, with a minimum of
7 °C and a maximum of
17.6 °C.
On the coldest nights of the month, the temperature usually drops to around
1 °C. However, it dropped to
-5.4 °C in April 2003.
On the warmest days of the month, the temperature usually reaches around
24 °C. However, it reached
27.9 °C in April 2003.
Precipitation amounts to
55 mm, distributed over 8 days.
The day lasts on average 13 hours and 25 minutes.
There are on average 7 hours of sunshine per day. So, the sun shines 51% of the time.
The average humidity is 68%.
The average wind speed is of
15 kph.
May is generally a very mild month. The average temperature is of
16.6 °C, with a minimum of
10.8 °C and a maximum of
22.3 °C.
On the coldest nights of the month, the temperature usually drops to around
6 °C. However, it dropped to
1 °C in May 1991.
On the warmest days of the month, the temperature usually reaches around
28 °C. However, it reached
32.3 °C in May 2003.
Precipitation amounts to
50 mm, distributed over 7 days.
The day lasts on average 14 hours and 35 minutes. So the days are long.
There are on average 8.5 hours of sunshine per day. So, the sun shines 59% of the time.
The average humidity is 64%.
The average wind speed is of
13.8 kph.
June is generally a warm month. The average temperature is of
20.9 °C, with a minimum of
14.6 °C and a maximum of
27.1 °C.
On the coldest nights of the month, the temperature usually drops to around
10 °C. However, it dropped to
5.2 °C in June 2005.
On the warmest days of the month, the temperature usually reaches around
33 °C. However, it reached
37.1 °C in June 2002.
Precipitation amounts to
55 mm, distributed over 5 days.
The day lasts on average 15 hours and 10 minutes. So the days are long. June 21, the summer solstice, is the longest day of the year in the Northern Hemisphere.
There are on average 9.5 hours of sunshine per day. So, the sun shines 63% of the time.
The average humidity is 59%.
The average wind speed is of
13.3 kph.
July is generally a warm to hot month. However, there are remarkable differences between night and day. The average temperature is of
24 °C, with a minimum of
17.3 °C and a maximum of
30.7 °C.
On the coldest nights of the month, the temperature usually drops to around
13 °C. However, it dropped to
10 °C in July 1991.
On the warmest days of the month, the temperature usually reaches around
35.5 °C. However, it reached
39 °C in July 2005.
Precipitation amounts to
30 mm, distributed over 3 days.
The day lasts on average 14 hours and 55 minutes. So the days are long.
There are on average 11 hours of sunshine per day. So, the sun shines 75% of the time.
The average humidity is 53%.
The average wind speed is of
14.4 kph.
August, the warmest month of the year, is generally a warm to hot month. However, there are remarkable differences between night and day. The average temperature is of
24.4 °C, with a minimum of
17.9 °C and a maximum of
31 °C.
On the coldest nights of the month, the temperature usually drops to around
13.5 °C. However, it dropped to
9 °C in August 1995.
On the warmest days of the month, the temperature usually reaches around
35.5 °C. However, it reached
40.1 °C in August 2017.
Precipitation amounts to
30 mm, distributed over 3 days.
The day lasts on average 13 hours and 50 minutes.
There are on average 10 hours of sunshine per day. So, the sun shines 74% of the time.
The average humidity is 56%.
The average wind speed is of
14.3 kph.
September is generally a warm month. The average temperature is of
19.9 °C, with a minimum of
14.3 °C and a maximum of
25.4 °C.
On the coldest nights of the month, the temperature usually drops to around
9.5 °C. However, it dropped to
6 °C in September 1995.
On the warmest days of the month, the temperature usually reaches around
30.5 °C. However, it reached
35.3 °C in September 2008.
Precipitation amounts to
70 mm, distributed over 6 days.
The day lasts on average 12 hours and 25 minutes.
There are on average 8.5 hours of sunshine per day. So, the sun shines 67% of the time.
The average humidity is 65%.
The average wind speed is of
14.4 kph.
October is generally a very mild month. The average temperature is of
15.5 °C, with a minimum of
10.8 °C and a maximum of
20.3 °C.
On the coldest nights of the month, the temperature usually drops to around
5 °C. However, it dropped to
0.8 °C in October 2012.
On the warmest days of the month, the temperature usually reaches around
25.5 °C. However, it reached
30 °C in October 2007.
Precipitation amounts to
75 mm, distributed over 7 days.
The day lasts on average 11 hours and 0 minutes.
There are on average 6.5 hours of sunshine per day. So, the sun shines 59% of the time.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is of
14.1 kph.
November is generally a mild month. The average temperature is of
10.7 °C, with a minimum of
6.8 °C and a maximum of
14.6 °C.
On the coldest nights of the month, the temperature usually drops to around
0 °C. However, it dropped to
-5 °C in November 1995.
On the warmest days of the month, the temperature usually reaches around
20.5 °C. However, it reached
25.3 °C in November 2004.
Precipitation amounts to
100 mm, distributed over 9 days.
The day lasts on average 9 hours and 50 minutes.
There are on average 4.5 hours of sunshine per day. So, the sun shines 45% of the time.
The average humidity is 78%. Hence, the air is normally humid.
The average wind speed is of
14.9 kph.
December is generally a quite mild month. The average temperature is of
7.1 °C, with a minimum of
3.4 °C and a maximum of
10.8 °C.
On the coldest nights of the month, the temperature usually drops to around
-3 °C. However, it dropped to
-10 °C in December 1996.
On the warmest days of the month, the temperature usually reaches around
16.5 °C. However, it reached
19.9 °C in December 2014.
Precipitation amounts to
65 mm, distributed over 8 days.
The day lasts on average 9 hours and 5 minutes. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.
There are on average 4 hours of sunshine per day. So, the sun shines 42% of the time.
The average humidity is 76%. Hence, the air is normally humid.
The average wind speed is of
16.2 kph.