Precipitation is quite scarce, although there can be periods of bad weather in winter.
, 90 km (55 mi) east of Los Angeles, at an altitude of 300 meters (1,000 feet). Just to the north, we find the San Bernardino Mountains, where the San Bernardino National Forest is located, while to the south-west we find the Santa Ana Mountains, which isolate the area from the ocean, making it hotter in summer.
, however, sometimes at night it can be cold, and the temperature usually reaches -1/-3 °C (27/30 °F) on colder nights.
Due to its location in an area surrounded by mountains, the city is also subject to air stagnation and therefore pollution.
, the days are often scorching, although the highest temperatures are recorded when the Santa Ana wind blows from the desert.
of the year, the temperature usually reaches 42/43 °C (108/109 °F). In July 2018, it reached 48 °C (118.5 °F).
To visit San Bernardino, you can choose the periods from mid-March to mid-April and from mid-October to mid-November. In winter, the weather is often mild and sunny, but sometimes it can be cold at night, and it can also rain.
. Here are the average temperatures.
January is generally a mild month. However, there are remarkable differences between night and day. The average temperature is of
12.9 °C, with a minimum of
5.9 °C and a maximum of
19.9 °C.

On the coldest nights of the month, the temperature usually drops to around
0 °C.

On the warmest days of the month, the temperature usually reaches around
27 °C.

Precipitation amounts to
80 mm, distributed over 6 days.
The day lasts on average 10 hours and 10 minutes.
The average humidity is 45%.
The average wind speed is of
4.9 kph.
February is generally a mild month. However, there are remarkable differences between night and day. The average temperature is of
13.7 °C, with a minimum of
7 °C and a maximum of
20.4 °C.

On the coldest nights of the month, the temperature usually drops to around
1.5 °C.

On the warmest days of the month, the temperature usually reaches around
27.5 °C.

Precipitation amounts to
105 mm, distributed over 7 days.
The day lasts on average 11 hours and 0 minutes.
The average humidity is 46%.
The average wind speed is of
5.9 kph.
March is generally a very mild month. However, there are remarkable differences between night and day. The average temperature is of
15.4 °C, with a minimum of
8.7 °C and a maximum of
22 °C.

On the coldest nights of the month, the temperature usually drops to around
4 °C.

On the warmest days of the month, the temperature usually reaches around
30 °C.

Precipitation amounts to
65 mm, distributed over 7 days.
The day lasts on average 12 hours and 0 minutes.
The average humidity is 49%.
The average wind speed is of
6.7 kph.
April is generally a warm month. However, there are remarkable differences between night and day. The average temperature is of
18.2 °C, with a minimum of
10.8 °C and a maximum of
25.5 °C.

On the coldest nights of the month, the temperature usually drops to around
5.5 °C.

On the warmest days of the month, the temperature usually reaches around
34 °C.

Precipitation amounts to
25 mm, distributed over 3 days.
The day lasts on average 13 hours and 5 minutes.
The average humidity is 43%.
The average wind speed is of
8.4 kph.
May is generally a warm month. However, there are remarkable differences between night and day. The average temperature is of
20.5 °C, with a minimum of
13.4 °C and a maximum of
27.6 °C.

On the coldest nights of the month, the temperature usually drops to around
9 °C.

On the warmest days of the month, the temperature usually reaches around
35.5 °C.

Precipitation amounts to only
5 mm, distributed over 2 days.
The day lasts on average 14 hours and 0 minutes.
The average humidity is 46%.
The average wind speed is of
8.6 kph.
June is generally a warm to hot month. However, there are remarkable differences between night and day. The average temperature is of
23.9 °C, with a minimum of
15.9 °C and a maximum of
32 °C.

On the coldest nights of the month, the temperature usually drops to around
12.5 °C.

On the warmest days of the month, the temperature usually reaches around
39 °C.

Precipitation amounts to only
0 mm, so on average it never rains in the whole month.
The day lasts on average 14 hours and 25 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 43%.
The average wind speed is of
8.7 kph.
July is generally a warm to hot month. However, there are remarkable differences between night and day. The average temperature is of
26.9 °C, with a minimum of
18.8 °C and a maximum of
35.1 °C.

On the coldest nights of the month, the temperature usually drops to around
14.5 °C.

On the warmest days of the month, the temperature usually reaches around
41 °C.

Precipitation amounts to only
0 mm, so on average it never rains in the whole month.
The day lasts on average 14 hours and 5 minutes. So the days are long.
The average humidity is 40%.
The average wind speed is of
8.8 kph.
August, the hottest 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
27.5 °C, with a minimum of
18.8 °C and a maximum of
36.1 °C.

On the coldest nights of the month, the temperature usually drops to around
14.5 °C.

On the warmest days of the month, the temperature usually reaches around
42 °C.

Precipitation amounts to only
5 mm, and all occurs in one day.
The day lasts on average 13 hours and 20 minutes.
The average humidity is 37%.
The average wind speed is of
8.3 kph.
September is generally a warm to hot month. However, there are remarkable differences between night and day. The average temperature is of
25.9 °C, with a minimum of
17.4 °C and a maximum of
34.4 °C.

On the coldest nights of the month, the temperature usually drops to around
11.5 °C.

On the warmest days of the month, the temperature usually reaches around
41 °C.

Precipitation amounts to only
5 mm, and all occurs in one day.
The day lasts on average 12 hours and 20 minutes.
The average humidity is 37%.
The average wind speed is of
7.5 kph.
October is generally a warm month. However, there are remarkable differences between night and day. The average temperature is of
21.2 °C, with a minimum of
13.3 °C and a maximum of
29.1 °C.

On the coldest nights of the month, the temperature usually drops to around
7.5 °C.

On the warmest days of the month, the temperature usually reaches around
37.5 °C.

Precipitation amounts to
20 mm, distributed over 2 days.
The day lasts on average 11 hours and 20 minutes.
The average humidity is 39%.
The average wind speed is of
6.7 kph.
November is generally a very mild month. However, there are remarkable differences between night and day. The average temperature is of
16.3 °C, with a minimum of
8.7 °C and a maximum of
23.9 °C.

On the coldest nights of the month, the temperature usually drops to around
2.5 °C.

On the warmest days of the month, the temperature usually reaches around
33 °C.

Precipitation amounts to
35 mm, distributed over 3 days.
The day lasts on average 10 hours and 25 minutes.
The average humidity is 37%.
The average wind speed is of
5.4 kph.
December, the coldest month of the year, is generally a mild month. The average temperature is of
12.5 °C, with a minimum of
6 °C and a maximum of
19 °C.

On the coldest nights of the month, the temperature usually drops to around
0 °C.

On the warmest days of the month, the temperature usually reaches around
26.5 °C.

Precipitation amounts to
60 mm, distributed over 5 days.
The day lasts on average 9 hours and 55 minutes. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.
The average humidity is 45%.
The average wind speed is of
5.3 kph.