Hayward's winters are mild, with temperatures ranging from freezing to the mid-teens Celsius, averaging around 11-12 degrees. Spring arrives in March, bringing gradually warmer days that can reach highs of up to 28 degrees by April, which averages 13 degrees. Summer months are warm, with July and August being the hottest, often reaching highs of 41 degrees, though temperatures usually average around 19 degrees. Autumn is characterized by a return to milder temperatures, with September and October seeing highs in the mid-twenties to low thirties Celsius. Winters tend to be cooler again, with December averaging just 9 degrees.