As is typical of continental climates, precipitation is most abundant in spring and summer, averaging close to 4 inches per month from May through August. Most of this rainfall is produced from showers and thunderstorms, the latter averaging 30 to 35 inches per year. Rainfall from such storms is sometimes intense but usually of short duration. Amounts of 0.7 inch in 30 minutes may be expected at Madera about once a year and 1.2 inches in 30 minutes once every 5 years. Up to 2.2 inches of rain can be expected in a 2 hour period about once every 10 years.
Autumn is usually the driest season of the year.
The 8.69 inches of precipitation normally received, however, is sufficient for agricultural and other economic pursuits. Although dry spells of varying durations can develop any time, extended rainless periods are most frequent in fall. Even under normal conditions, measurable precipitation is recorded on only 8 days per month during September and October. From November through March, much of the precipitation is in the form of snow or a mixture of snow and rain. Seasonal snowfall averages 45 inches but has ranged from 33 to 76 inches over the period of record, the latter amount occurring during the 1963-1964 season when 20 inches plus was recorded monthly from December through February.