Block Island, RI tide times

Block Island sits 21 kilometres south of Point Judith in Block Island Sound, isolated enough from the mainland to have developed a distinct ecology and character. The tidal regime here reflects the island's open Atlantic position: mean spring range is around 0.7 metres — lower than the Rhode Island mainland coast because the island's offshore location is less influenced by the tidal amplification in Narragansett Bay. The twice-daily cycle is regular but subtle, and the primary water-level driver on storm days is wind setup rather than the astronomical tide.

The Great Salt Pond occupies the northwestern third of the island — a 1.5-square-kilometre sheltered harbour enclosed by a narrow barrier beach, with the entrance channel through the Cut at the northwest corner. The Cut is the tidal exchange point for the entire salt pond, and the current through it runs to 2 knots on spring tides. The ferry from Point Judith enters the Great Salt Pond through the Cut and ties up at Old Harbor on the east side of the island; boats anchored in the pond use the Cut timing for entry and exit. New Harbor on the Salt Pond is the active marina and anchorage hub for cruising yachts.

Old Harbor is the traditional commercial and social centre — the Victorian-era hotel district, ferry dock, and main street shops are all concentrated in the few blocks above the east-facing beach. Southeast Light (1875, one of the most powerful lighthouses on the Atlantic coast at 67 metres above sea level on the Mohegan Bluffs) was moved 30 metres inland in 1993 as coastal erosion threatened its foundation — the bluffs actively erode at approximately 1 metre per year.

The Mohegan Bluffs on the south coast are a 12-kilometre line of clay and sand cliffs 20 to 30 metres high, with a staircase descent to the beach below. At low water, the rocky ledge platform below the bluffs extends 50 to 80 metres offshore and supports good tide pool communities. The exposed ledge is accessible for about 2 hours either side of low water before the incoming tide covers the lower sections.

Block Island is one of the most important bird migration stopovers in New England. The island's isolated position in the Atlantic concentrates tired migrants during northeast wind events in autumn — rare and uncommon species including Connecticut warblers, Philadelphia vireos, and western rarities appear annually. The Nature Conservancy owns approximately 40% of the island in protected land. The combination of lighthouse, Mohegan Bluffs, and freshwater ponds (Sands Pond, Fresh Pond) provides diverse habitat.

Surf casting from the southern beaches and the rocky shoreline at Sandy Point (north) produces striped bass from late May through October. The current rips off the southwest corner where Sound and open Atlantic tidal streams meet are productive for bass and bluefish when the current is running. The Block Island chapter of the Saltwater Anglers of Rhode Island has traditional spots documented over decades.

Predictions on this page come from Open-Meteo Marine, a gridded global ocean model. Accuracy is typically within plus or minus 45 minutes on timing and 0.2 to 0.3 metres on height — model-derived, not from a local gauge. For authoritative US tide data, consult NOAA CO-OPS at tidesandcurrents.noaa.gov.