Using java - using if else statement in a switch?

I'm pretty new to Java, and coding in general. In my class we need the user to input the month (1-12) and a day (1-30) and we determine on a set date (june 15 to sept 30th) if it is or is not monsoon season. I'm trying to use a if else statement in a switch to say that anytime before june 15 is not monsoon season but my code keeps showing both if and else statement. Any help is welcomed, thank you!

import java.util.*;

public class Monsoon

 {  public static void main (String[]args)
    {
    Scanner kb = new Scanner (System.in);



    // Prompt the user to enter month & Day
    System.out.print("Please enter a month(1-12) and day (1-31): " );
    int month = kb.nextInt();
    int day = kb.nextInt();


    // using a switch statement to show months
    switch (month){
        case 1:
            System.out.println("is NOT monsoon season");
            break;
        case 2:
            System.out.println("is NOT monsoon season");
            break;
        case 3:
        System.out.println("is NOT monsoon season");
            break;
        case 4:
            System.out.println("is NOT monsoon season");
            break;
        case 5:
            System.out.println("is NOT monsoon season");
            break;
        case 6:
            System.out.println("“is monsoon season");

            // use if else statement so user knows that before june 15 is not monsoon season
        if (day>=15)
            System.out.print("it is monsoon season");
        else
            System.out.print("it is not monsoon season");


            break;
        case 7:
            System.out.println("“is monsoon season");
            break;
        case 8:
            System.out.println("“is monsoon season");
            break;
        case 9:
            System.out.println("“is monsoon season");
            break;
        case 10:
            System.out.println("is NOT monsoon season");
            break;
        case 11:
            System.out.println("is NOT monsoon season");
            break;
        case 12:
            System.out.println("is NOT monsoon season");
            break;

        default: System.out.println("not valid");
        break;

    }

}

}