A couple updates to the directions:
Easiest way is to take 95 north or south to exit 92 east ( t'wards the shore & not Foxwoods
). You will come to a light at a large intersection and take a left (you'll see signs for Westerly & the Rhode Island Beaches - RT 78). About half mile on right is the ramp for route 78 which will bring you almost to Watch Hill & Weekapaug after 5 miles or so. At the end is RT1, take a left to go north. At the nexy major Intersection is Dunne's Corner, take right. This is Weekapaug Rd. You'll go straight thru 1 intersection at RT1a and travel abouit 1.5 miles, water from the inlet at Weekapaug Breachway will be on your right. Shortly after docks on your right, you'll see the bridge on Atlantic Ave going over the inlet (just before the breachway). Weekapaug B&T is the second building on your right, head to the back parking lot...
If all else fails, look for smoke from grilles
Steve - you should try going 95, often faster when you're going all the way to Westerly... You can also take the last exit in Rhody for Watch Hill (RT3 I think) and that will take you to 78 as well but that can be real slow with traffic sometimes...