There is a recent thread on Meta on the matter at hand (see Can we please have a way to sort threads in a sub-forum as per merit?). While there is no implemented sorting feature as such, you can check the thread suggested by @jacee and the top merited official stats (see https://bitcointalk.org/index.php?action=merit;stats).

In the first mentioned thread, I included the alternative to use the Merit Dashboard, click on the Rankings tab, and filter at the top by one of the section/subsection of preference.
On the right hand of the screen you’ll see a sorted list by merit accumulated in the thread, list that can be delimited to a period of time such as last month for example. You then need to locate the thread on Bitcointalk, since there is no hyperlink to the thread in this case (The Dashboard hyperlinks to specific posts, but not entire threads).