When you start your blog you may have no conception of how long you're going to be doing this for or the time and effort that it is going to take on your part, but when you become a seasoned blogger, you'll be able to look back (and look forward) and see your personal seasonal rhythms with your blog.
We all have our ups and downs and habits that we get into, and our blogs will reflect that over time. Right now, it's getting into fall, and for a a lot of people summer is one of two extremes - it is either the time where you're lazy and don't maintain your blog as much, or you're coasting along with your blog because everyone is engaged and involved. After this, you're going to have to make one transition or another - either get more involved with your blog and write more or expect less involvement from your audience. Or you're one of those lucky few that get consistent involvement year round - know I strongly dislike you.
For those who are just starting - know that you will likely get into routines in different seasons (the weather may not correlate...but it will happen.) Blogs have life cycles and phases just as a business does. You'll probably get into a winter funk, and there will be some bumps and scrapes along the way - balancing life, work and blog isn't always easy.
As I said, your seasons may not match what you're seeing outside of the window, but you really should take note of what kind of life cycle your blog has, where the ups and downs and peaks and valleys usually occur. If you don't notice these things, your blog could become completely stale or irrelevant without you noticing. Years will run by you, and your blog hasn't grown or evolved at all. Maybe you don't get to know your audience, or haven't don't any kind of SEO, but SEO is a whole 'nother topic.
Just as a fact of life in the real-world seasons of Fall and Winter, you will be faced with a lot more holidays - from Halloween to Christmas. You'll need to decide to what degree you're going to want to share your personal experiences of the holidays, or the ways in which you're going to allow the holidays you do (or don't) celebrate color your content.
The winter of your blog is a test of discipline. Long days and little to show, at this point you're just trying to get through your posting schedule. You don't have the heart to start any new promotions or launch any new projects. You just slog through the mud and keep on keepin' on. Do you have the devotion to really keep doing this blog? Your winter is your benchmark.
Spring - buds are blooming, birds are chirping, the sun is shining. In short, things are looking better. You've got new subscribers or maybe you just got pitched a great promotional deal, but things are going so much better than they were. Whatever is making you excited about your blog again, you're posting so much more and are engaged and active, riding on cloud 9.
As I've mentioned earlier, the summer of your blog (which likely corresponds to the actual season) can be one of two things. Either you're hot and lazy and kind of abandon ship with your blog, posting less frequently, engaging less often, or you're continuing the high of summer and you could almost be on vacation because things with your blog are evolving so naturally and everything is going so easily.
The fall of your blog is the time that you need to take to analyze your blog. Do you need a new design? (Do you want a new design?) Do you need to reach out to a different audience? Guest post somewhere? Start in on a new topic or a new angle? Fall is the time to ask those questions, and figure out what is going on a bit deeper with your blog - figure out how to grow it, how to nurture it.
Don't forget your blog is a reflection of you, and you go through cycles and rhythms. Follow them, understand them. Don't try and fight them or get frustrated with it. Ups and downs happen with everything. Keep in mind the larger picture of you and your blog and how they fit together - and a big part of that is identifying and acknowledging the rhythms that your blog goes through.