Climate - Modesto (California)

The climate of Modesto can be defined as Mediterranean, given that the winters are mild and rainy, and the summers are hot and sunny. However, there are some differences in comparison with the typical Mediterranean climate: in winter, fog can form at night and in the early morning; in summer, there are strong diurnal temperature variations, so it is quite cool at night and hot during the day; the rainy period is shorter, so in autumn, in September and October, it still rains rarely.
The city is located in the northern part of San Joaquin valley. Here, the difference in temperature between night and day and between winter and summer are much larger than in San Francisco, which is located 125 km (75 mi) to the north-west.
On the coldest days of the year, the temperature generally drops to -1/-3 °C (27/30 °F) at night, while it reaches about 10 °C (50 °F) during the day. But in December 1990, it reached -7 °C (19.5 °F). Snow is extremely rare: in practice, it never snows. On the days when there is no fog and no rain, the temperature can reach 18/19 °C (64/66 °F) even in the middle of winter.
On the hottest days of the year, the temperature can reach 40/42 °C (104/108 °F). In August 2017, it reached 43 °C (109.5 °F), and in July 2006, even 45 °C (113 °F). It can sometimes be very hot even in late April and early October. However, since the daytime temperature range is very strong, generally, at night it gets quite cool even in the height of summer.
The average temperature of the coldest month (December) is of 8.7 °C (48 °F), that of the warmest month (July) is of 26.2 °C (79 °F). Here are the average temperatures.

Precipitation amounts to 335 millimeters (13.2 inches) per year: it is therefore quite scarce (although in winter there may be periods of bad weather). It ranges from 0 mm (0 in) in the driest months (July, August) to 65 mm (2.6 in) in the wettest (January). Here is the average precipitation.

Best Time

The best times to visit Modesto are spring and autumn, to avoid the night-time cold, the fog and the rain of winter, as well as the summer heat. In particular, you can choose the months of April and October, bearing in mind that it is necessary to dress in layers because there are strong temperature differences between night and day.

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