Yes the fourth month is April
in December
October 21
Officially, winter begins with the Winter Solstice on December 21.
Winter begins on or about June 21 in the southern hemisphere.
March
October 1
spring and autumn begin midway between the two solstices. these are the aquinoxes.
October 1
Traditionally it has been the month of September.
August
It depends where you are and what year it is.