Translation:Winter is arriving soon!
The 了 can also be used when something is about to happen, normally paired with 快 (kuài), 快要(kuàiyào) or a 要 (yào) according to the following:
You wrote that a year ago; it seems Beta will go on forever because nothing has changed. Sure it's a free course, but they should tell people that you are going to get marked wrong over and over again because they don't have enough variation in English answers. Their doing, not anyone studying the course's fault.
For those that like to hang in and get the course completed it's an unpleasant pain which they seem never to do anything about, even if you report the answer you have.
Other courses have moderators who read the blogs but not this one.