Having lived in Newfoundland for 24.5 years, left 2008.
Gros Morne National Park has all year cg at Green Point. & one can boondock.
Well remember RobandDi rushing up to the Northern Peninsula May 18 (well, teens anyway) being afraid that the icebergs would melt. (
http://www.icebergfinder.com/) Heck that site doesn't track icebergs at all until May 1.
Speaking of ice
http://weather.gc.ca/mainmenu/marine_menu_e.html ice reports. You want: Atlantic - all 3, St. Lawrence, Sea Ice--Eastern. Most important I think is ice in the Strait of Belle Isle, that between Labrador and Newfoundland. & pay attention to any kinds of fishing activity at that time of the year. Or, if there is ice in the Strait of Belle Isle the west of Newfoundland will have a cool spring.
& yes, I expect that will happen this year. That's not to say you can't have a good time in such weather. Heck, few if any no-seeums or black flies.
Meanwhile, the trad. Newfoundland view:
Buddywasisname, The Gravel Pits:B