Tide charts / Massachusetts

Massachusetts tide charts

Every NOAA tide prediction station on the Massachusetts coast that returned high and low waters when this site was built: 6 of them. The table ranks the coast by mean tidal range, because that is the number that decides how much of a beach, a flat or a ramp is uncovered between one high water and the next — and it is not constant along a single state's shoreline.

Stations ranked by mean tidal range

Mean range below is the average height difference between one predicted extreme and the next, computed over the same seven days for every station in the table, beginning Saturday, October 17. It is derived from NOAA's own predicted extremes; it is not a NOAA-published statistic.

NOAA tide prediction stations in Massachusetts, ranked by mean range over the same seven days beginning Saturday, October 17. Heights in feet above mean lower low water.
Station	Mean range, ft	Largest swing, ft	Prediction type	Stored through
Boston 8443970	7.09	8.96	From the water level listing	2026-10-23
Chatham 8447435	4.12	4.93	From the water level listing	2026-10-23
Fall River 8447386	2.82	4.1	From the water level listing	2026-10-23
New Bedford Harbor 8447636	2.31	3.52	From the water level listing	2026-10-23
Nantucket Island 8449130	2.29	2.88	From the water level listing	2026-10-23
Woods Hole 8447930	0.89	1.72	From the water level listing	2026-10-23

Ranked from the stored predictions described on the methodology page. Stored windows are uneven because the fetch tool used at build time summarised long NOAA responses rather than reproducing them, which the methodology page records; the printable tide chart tool requests any dates you want from NOAA directly.

What the spread in this table means for you

At Boston the water moves 7.09 ft between extremes on average; at Woods Hole it moves 0.89 ft. That is the same ocean on the same day, and it is why a tide chart for one Massachusetts town is not a tide chart for another one down the coast. Picking the station nearest your spot matters more than any other choice on this site.

The spacing matters too. Successive high waters sit about 12 h 25 min apart, so a tide that falls at a convenient hour this weekend falls roughly fifty minutes later each day and is inconvenient within a week. Each station page carries that station's own measured spacing over its stored window rather than the textbook figure.

Two stations a few miles apart can also differ in timing, not just range, because a subordinate station's predictions are time-and-height offsets applied to a reference station's harmonic predictions. Where a station is subordinate, the table above names the reference station its numbers are derived from, and so does its own page.

Every Massachusetts station, with its own curve

RisingFalling

Boston tide chart Station 8443970 at 42.35389, -71.05028. Mean range 7.09 ft over the week shown. Highest in the stored window 9.72 ft, lowest 0.759 ft.
Chatham tide chart Station 8447435 at 41.6885, -69.9511. Mean range 4.12 ft over the week shown. Highest in the stored window 4.984 ft, lowest 0.053 ft.
Woods Hole tide chart Station 8447930 at 41.523613, -70.67111. Mean range 0.89 ft over the week shown. Highest in the stored window 2.076 ft, lowest 0.355 ft.
Nantucket Island tide chart Station 8449130 at 41.285, -70.0967. Mean range 2.29 ft over the week shown. Highest in the stored window 3.329 ft, lowest 0.408 ft.
New Bedford Harbor tide chart Station 8447636 at 41.6212, -70.9137. Mean range 2.31 ft over the week shown. Highest in the stored window 3.8 ft, lowest 0.275 ft.
Fall River tide chart Station 8447386 at 41.7043, -71.1641. Mean range 2.82 ft over the week shown. Highest in the stored window 4.452 ft, lowest 0.354 ft.

What these predictions are, and what they are not

Every number on every Massachusetts page here is an astronomical tide prediction from NOAA's CO-OPS predictions product: the tide the sun and moon would produce on their own. Wind, atmospheric pressure, river discharge and storm surge are not in them. A nor'easter can hold the water well above the predicted line for a day; a hard offshore wind can hold it below. Nothing on this site tells you whether a place is safe to walk, swim, anchor or cross.

Times of slack water — when a tidal current stops running — are a different quantity again, predicted from a different NOAA product, and they do not share a clock with high and low water. High tide vs slack tide works through why.

Heights are feet above mean lower low water, the datum NOAA uses for US tide predictions. A predicted height of 1.0 ft does not mean a foot of water under a hull: it means the surface is predicted to sit a foot above chart datum, and the depth anywhere is whatever the chart says plus that number.