Perfectly flat glassy water, tidal, but always over your head. The water is always dirty. At low tide it does get shallow up next to the jetty near the beach. Watch for rocks on the bottom. Can easily snag a fin or your board. Also no fun to fall on one either. Rock wall around upwind side in a southerly, which makes for the most amazing glass riding anywhere. This is why experienced riders go here.
Beach is around approximately 2/3rds of the enclosed area. A sailing center is downwind and there are two dam like openings, in the wall, through which the tide flows through. When the tide is outgoing, you need to stay well clear of this area. Launching is tight but there is enough room. Good quality sand. The beach is tight at high tide. Launch is at southwest corner of the bay. Launching can be tricky here and is not for beginners. Assisted launching is highly recommended even for advanced riders. Completely enclosed, it is a half mile circle. This is not a beginner spot. If you can't self rescue, self land, and stay upwind you should not ride here, period.
New England weather is anything at anytime. May through October are realistically the times to go. Can be snowing in the months other than these. Beware of putting your kite up in a light easterly, as wake vortexes from jets can make it down to the surface, very dangerous! Wetsuits required almost all year, except for late July and August, when you sometimes can go without. Hot and humid in summer. Cold and icy in winter.
10-20 is your average wind. Very gusty. You want to ride it in a southerly for the most part. Northerlies you need to go somewhere else, though it works in an easterly but there are better spots from this direction locally. Not a beginner spot, the gusty wind will drive you nuts, and you will drive other people nuts. Sometimes not a lot of wind right on the surface, which makes relaunching your kite tricky, and of course there are the dams where the water flows in and out with amazing velocity. But the good directions for this site is SW through E.
93 to the JFK/Umass exit, then go left, to the rotary, get on O'Day Boulevard, and go along water till you hit the circular water area. This is Pleasure Bay. Most of the time you will launch adjacent to the rock wall, but still on the beach, right near where the beach ends and the rock wall starts. Parking can be tight in the summer but you will find something.
No kitesurfing when lifeguards area present (summer, 10am to 6pm). Respect the local beach goers, there can be a lot. Off limits in July and August during the day. Not a good beginner spot, go to Revere, Nahant or Nantasket instead until you can stay upwind. There is a wind shadow at the launch on Southerlies, so the wind is super gusty. Ask a local about local issues and restrictions. If no one is kiting there it's because the condition are wrong. Do not go out. Spot is in jeopardy for the future, so be very careful. There is also absolutely no body dragging inside P Bay. You will just get in the way of others and if you drop your kite in the drink you will never get it back up. There are various wind shadows depending on the direction of the wind. So this is a tricky spot to ride and even advanced riders sometimes have to do the swim across the bay because they can not relaunch their kite off the water. This also means that this is not a spot for flying trainer kites. A number of kiters have put their kites in the power lines behind the road on the downwind part of the bay. You can fly trainer kites on the outside beach near the sailboats but watch for people. A better beginner beach in Boston is Revere Beach.
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