Chatham, MA tide chart
High and low waters at NOAA tide prediction station 8447435, Chatham, in feet above mean lower low water and in local clock time. Tables below are grouped by calendar month, so each one stays correct for the whole month it names.
Predictions stored for Saturday, October 17 to Friday, October 23 (7 days, 27 high and low waters), retrieved from NOAA on 2026-10-17.
The week of Saturday, October 17
Water rising (flood)Water falling (ebb)Now, when your browser can draw it
Tide times at Chatham, October 17–23, 2026
Stored predictions cover October 17 to 23 only, so this table is a part month. The full month is available from NOAA through the printable tool.
| Date | Tide | Time (local) | Height, ft above MLLW |
|---|---|---|---|
| Saturday, October 17 | High | 5:33 a.m. | 4.089 |
| Low | 11:25 a.m. | 0.721 | |
| High | 5:25 p.m. | 4.823 | |
| Sunday, October 18 | Low | 12:30 a.m. | 0.313 |
| High | 6:27 a.m. | 3.962 | |
| Low | 12:18 p.m. | 0.729 | |
| High | 6:22 p.m. | 4.658 | |
| Monday, October 19 | Low | 1:22 a.m. | 0.325 |
| High | 7:22 a.m. | 3.946 | |
| Low | 1:15 p.m. | 0.688 | |
| High | 7:21 p.m. | 4.586 | |
| Tuesday, October 20 | Low | 2:14 a.m. | 0.285 |
| High | 8:14 a.m. | 4.051 | |
| Low | 2:13 p.m. | 0.585 | |
| High | 8:18 p.m. | 4.608 | |
| Wednesday, October 21 | Low | 3:02 a.m. | 0.223 |
| High | 9:02 a.m. | 4.268 | |
| Low | 3:10 p.m. | 0.434 | |
| High | 9:11 p.m. | 4.701 | |
| Thursday, October 22 | Low | 3:49 a.m. | 0.165 |
| High | 9:46 a.m. | 4.578 | |
| Low | 4:04 p.m. | 0.251 | |
| High | 10:00 p.m. | 4.836 | |
| Friday, October 23 | Low | 4:33 a.m. | 0.127 |
| High | 10:27 a.m. | 4.958 | |
| Low | 4:56 p.m. | 0.053 | |
| High | 10:47 p.m. | 4.984 |
Printed from TideCurve. Predictions: NOAA CO-OPS station 8447435, datum MLLW, stored range 2026-10-17 to 2026-10-23, retrieved 2026-10-17. Astronomical predictions only.
Pick any dates for Chatham in the printable tool, which requests them from NOAA when you open it.
What the numbers at this station mean
Heights are feet above mean lower low water, the datum NOAA uses for tide predictions on US coasts. A predicted height of 0.053 ft does not mean 0.053 ft of water under a boat: it means the surface is predicted to be 0.053 ft above the chart datum, and the depth at any spot is whatever the chart says plus that number.
- Mean range across the stored period. The average height difference between one extreme and the next is 4.12 ft here, with the largest single swing 4.93 ft and the smallest 3.23 ft.
- Spacing. Successive high waters sit 12 h 24 min apart on average, which is why a tide that is convenient this morning is inconvenient within a few days.
- Type. This station returned 14 high waters and 13 low waters across 7 days. Where those counts are not close to two a day, the station's tide is not a simple twice-daily cycle and the curve above will look it.
Station provenance
| NOAA station | Chatham (8447435), Massachusetts |
|---|---|
| Coordinates | 41.6885, -69.9511 |
| Prediction type | Not recorded in the metadata record this station came from. The station is in NOAA's water level station listing and returns predictions from the predictions product. |
| Datum | MLLW — mean lower low water |
| Units | Feet |
| Time zone | America/New_York. Requested with time_zone=lst_ldt, so NOAA returns local standard time corrected for daylight saving time while it is in effect. Times on this page are clock times at the station, and no second conversion is applied anywhere. |
| Stored coverage | 2026-10-17 to 2026-10-23 — 7 days, 27 predicted high and low waters, served at /data/tides/8447435.json |
| Retrieved | Station metadata 2026-10-16; predictions 2026-10-17 |
| Request | https://api.tidesandcurrents.noaa.gov/api/prod/datagetter?product=predictions&datum=MLLW&station=8447435&time_zone=lst_ldt&units=english&interval=hilo&format=json&begin_date=20261017&end_date=20261023 |
| Source | NOAA CO-OPS Data API, public domain. Station metadata from the CO-OPS Metadata API. |
What these predictions are not. They are astronomical: the tide the sun and moon would produce on their own. NOAA's own FAQ puts it plainly — "we can only predict the astronomical tides" and not "the effect that wind, rain, freshwater runoff" have on the water level (NOAA Tides & Currents FAQ). A storm, a strong onshore wind or a wet week can put the water well above the line, and a hard offshore wind can hold it below. Nothing on this page tells you whether a place is safe to walk, swim, anchor or cross, and times of slack water are a different quantity again — see high tide vs slack tide.
Nearby stations
Predictions change along a coast, inside a harbour and up an estuary. If your spot is closer to one of these, use that station instead.
- Nantucket Island, MA — station 8449130, about 29 mi away
- Woods Hole, MA — station 8447930, about 39 mi away
- New Bedford Harbor, MA — station 8447636, about 50 mi away
- Fall River, MA — station 8447386, about 63 mi away
- Boston, MA — station 8443970, about 73 mi away
Or see every station on the list and how these pages were built.