The pioneering cryptozoological writer Bernard Heuvelmans was once told that sea serpent sightings appeared in the paper because summer was "the silly season" when reported needed to fill the paper up and were happy to put in some fanciful topics. No one can actually find such a pattern, and having more sighting reports of lake, river, and seacoast animals is pretty easily explained by the fact there are more people on and around the water in summer to either 1) see mysterious creatures, or 2) see things they mistake for mysterious creatures.
As Loren Coleman writes here, August 2013 got really busy. Chronologically, in early August, David Elder, an amateur photographer, saw something in Loch Ness. He got both still photographs and video. Loren reports that Henry Bauer and Gary Campbell, veteran Loch investigators, think Elder photographed a wave or wake effect, which is probably right but, of course, disappointing. At Loch Morar, two people reported a 20-foot creature. It was seen three times in two days and photographed (alas, inconclusively).
Two men kayaking off Acadia National Park in Maine reported a "sea serpent" swimming by with a three-foot-long head covered with scales. A swimming creature off that coast might well be a moose (despite their ungainly appearance, these big lummoxes are actually nimble on land and swim well enough that they are often seen crossing water to favorite grazing spots or whatever else turns a moose on.) The three-foot length could be the product of excited exaggeration. The scales are odd: wet, ruffled-up fur can look like anything besides what it is, but I'm not sure about scales. On the other hand, as cryptozoological researcher Jay Cooney points out here, elephant seal hide can look like scales, too.
So do we have an outbreak of unclassified aquatic creatures, or just a coincidental conflux of mistakes? The conservative choice is the latter, and I personally don't hold out hope for any of the "lake monsters." But I would like to have been in that kayak....