There are two types of topics that you can write about. Topics that will bring you always bring your traffic, and those that may be interesting right now, but will burn out in a few days, sometimes weeks, better known as a trend.
Though it may be good to focus on content that will be useful for years, but following a trend and benefit from the surge of interest while it lasts won’t hurt. Following a trend can bring traffic that doesn’t normally come to your site, with those users coming back regularly if the content motivates them.
You can find trending conversations on both Google Trends and Twitter.