So what can we do about it? How do we keep from destroying our writing habits? Here are a few ideas.
Maybe you can't write for an hour every day. How about twenty minutes three times a week? Whatever your schedule allows, try to do it. You might keep up your usual routine, but any kind of routine at all is better than a summer of no writing at all.
Do you have friends who write? Are you part of a writing group? Sometimes you can jump start your writing by getting together with other writers. Meet wherever you can, even if only for a couple hours, and write away. You can spend some of the time socializing or discussing writing problems, but make sure you leave plenty of time to write. One tip: don't get together in somebody's home. That's not going to work for the host. Unless, of course, there's nobody else at home and so it's quiet and comfortable with minimal distractions.
Prioritize Your Writing Days
Set regular writing days and decide that you won't do anything else until you've written to your goal, whatever that is. Make sure your family knows that you are unavailable for that time, but that you'll do whatever they want and whatever else needs to be done when you've finished. This works best, of course, if you don't have small children and you have a somewhat private writing area. You might have to start early or stay up late, whatever works best for you, to avoid all those other things you need to do. You might not be able to do this every day, but if you have scheduled writing days and your family understands that you need that writing time and that it's your time, it can work.
You might be too tired to write by the time things quiet down at night, but that gives you time to deepen the research for your story. You can either read a book or, if you don't have time to devote to that, surf the web. While surfing the web, you can make a list of potential agents.
Just Accept It
Finally, you might just have to accept that summer is not a good time for you to write. If you have young kids who are out of school or other summertime distractions, you might have to take the summer off, or accept that your production will take a nose dive. If you're in this situation, just accept it. Don't feel guilty. You have priorities, and some of those might be higher than writing. There's no shame in that. You haven't failed. You're doing what's most important to you during those months. It's OK. It can actually be a good thing. Sometimes it helps your story if you can set it aside for a while and let it simmer. Your brain is still working, and you'll come back to the work with fresh eyes when school starts. Those fresh eyes will help you identify weak places you didn't see when you were in the heat of creativity.
These are just a few suggestions. Maybe something else works for you. The point is, if you need a different routine in the summer, or if you're not able to write as much, it might just be the way things are for the life you want to live. Summer won't last forever.