Ontario
California, USA
Long-term weather forecast
Long-term weather forecast

May weather forecast and climate
Ontario, CA

A clear street near the luxurious residential estate in Ontario, California, with a scenic background of a hilly landscape, the clear blue sky
A clear street near the luxurious residential estate in Ontario, California, with a scenic background of a hilly landscape, the clear blue sky
May, the last month of the spring, in Ontario, is also a moderately hot month, with temperature in the range of an average high of 79°F (26.1°C) and an average low of 55.6°F (13.1°C).

Temperature

In May, the average high-temperature is relatively the same as in April - a still warm 79°F (26.1°C). The average low-temperature, in May, is 55.6°F (13.1°C).

Rainfall

During May, Ontario regularly aggregates up to 0.3" (7.6mm) of precipitation. During the entire year, Ontario aggregates up to 15" (382mm) of precipitation.

Daylight

The average length of the day in May in Ontario is 14h.

What is the temperature in May in Ontario?

In May, in Ontario, California, the average high-temperature is 79°F (26.1°C), and the average low-temperature is 55.6°F (13.1°C).

How much does it rain in Ontario in May?

In Ontario, in May, 0.3" (7.6mm) of precipitation is typically accumulated.

What is the average length of the day in May in Ontario?

The average length of the day in May in Ontario is 14h.
Average temperature in May - Ontario, CA
  • Average high temperature in May: 78.9°F

The warmest month (with the highest average high temperature) is August (93.6°F).
The month with the lowest average high temperature is January (65.2°F).

  • Average low temperature in May: 55.5°F

The month with the highest average low temperature is August (64.7°F).
The coldest month (with the lowest average low temperature) is December (42.7°F).

Average rainfall in May - Ontario, CA
  • Average rainfall in May: 0.3"

The wettest month (with the highest rainfall) is February (3.4").
Driest months (with the lowest rainfall) are June, July and August (0.1").

Average daylight in May - Ontario, CA
  • Average daylight in May: 14h

The month with the longest days is June (Average daylight: 14.4h).
The month with shortest days is December (Average daylight: 9.9h).