public boolean isSunnmerOrWinterMonth(int month)

Given a number in the range 1-12 that represents a month in the year (1=Jan, 2=Feb, etc), return true if either SUMMER or WINTER occurs in that month, false otherwise. The months in which SUMMER occurs are June-September. The months in which WINTER occurs are December-March.

public boolean isSummerOrWinterMonth(int month) {
  boolean summerMonth = false;
  if (6 <= month && month <= 9) {
    summerMonth = true;
  }

  boolean winterMonth = false;
  if ( month == 12 || (1 <= month && month <= 3) ) {
    winterMonth = true;
  }

  boolean summerOrWinterMonth = false;
  if (summerMonth || winterMonth) {
    summerOrWinterMonth = true;
  }
  return summerOrWinterMonth;
}