@jayawickrama If you don't want to set up a new schedule try IFTTT. It will take some setup, but after that it can be as easy as adding a watering event to your calendar. You can keep the channel and calendar forever, but only use it when you need to without having to repeat the setup.
@jayawickrama Here's a link to how I use it to skip the days that my landscaper comes.
If you don't want to use a calendar, you can even set up an IFTTT channel to water when you send yourself an email with a certain subject or tag. If you have time it's a fun thing to play around with, and you'll find you can use it for all kinds of stuff outside of using it with your Rachio.