Haven't been out myself yet, but here's the latest fishing news from the Granite State:
"Coldwater anglers on the big lakes are reporting the thermocline (the water "layer" where warmer and cooler waters meet) is rapidly setting up at 25-30 feet; once the insect hatches settle down, look for action to really pick up over the next two months.
I have caught some decent 14-18 inch rainbows in Winnisquam, at 30 feet on the downrigger and 4-5 colors of lead core line.
DB Smelts and Guide Specials (you name the color -- it works) have been productive. Balls of baitfish (smelt) are beginning to show up on the bottom in 40-60 feet of water. This is the critical time of year when one-year-old landlocked salmon feed voraciously on young-of-the-year (YOY) smelt."
http://www.wildlife.state.nh.us/Fishing/fishing.htm