It typically occurs in cool, wet spring and fall weather.

Snowfall can occur in winter and early spring, although it is not very common away from high ground.

The floods of the Mississippi usually occur in spring or summer.

More changes occurred in spring 2006, when the position of video producer was introduced to the staff.

Most events occur in spring and summer, when there are up to three events a week.

Cases usually occur in late winter and early spring.

Another excavation occurred one year later, in late winter and early spring of 1991.

This usually occurs in the late autumn or early spring.

The moulting season occurs in late spring and is a process that takes six to eight weeks.

Activity occurred throughout the day in late winter and early spring.