Tides Today & Tomorrow in Boston, MA

TIDE TIMES for Monday, August 17, 2026
The tide is currently rising in Boston, MA.
Next low tide : 9:13 am (0.4 ft)
Next high tide : in 1h 30m at 3:06 am (10.1 ft)
Sunset today : 7:42 pm
Sunrise tomorrow : 5:53 am
Moon phase : Waxing Crescent (27% illuminated)
Tide Station Location : Station #8443970
Common Questions About Tides

Boston, MA Tides - Feb 1937

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Mon2:499.43:118.99:010.79:190.86:574:57Third Quarter1Mon
2Tue3:349.24:018.49:511.010:071.36:564:58Third Quarter2Tue
3Wed4:239.04:558.010:441.310:571.66:555:00Third Quarter3Wed
4Thu5:158.85:517.711:391.411:501.86:545:01Third Quarter4Thu
5Fri6:098.86:507.612:361.46:535:02Waning Crescent5Fri
6Sat7:058.97:477.812:441.91:321.36:525:04Waning Crescent6Sat
7Sun7:599.18:408.11:391.72:250.96:505:05Waning Crescent7Sun
8Mon8:499.59:268.52:311.43:120.56:495:06Waning Crescent8Mon
9Tue9:349.910:088.93:190.93:560.06:485:08New Moon9Tue
10Wed10:1710.310:489.44:040.44:37-0.46:475:09New Moon10Wed
11Thu10:5910.611:289.94:48-0.15:18-0.86:455:10New Moon11Thu
12Fri11:4310.85:33-0.55:59-1.06:445:11New Moon12Fri
13Sat12:1010.312:2710.86:18-0.86:42-1.16:435:13Waxing Crescent13Sat
14Sun12:5210.61:1310.67:04-0.97:26-1.06:415:14Waxing Crescent14Sun
15Mon1:3710.72:0110.37:53-0.98:13-0.76:405:15Waxing Crescent15Mon
16Tue2:2410.72:539.98:45-0.79:04-0.36:395:17First Quarter16Tue
17Wed3:1610.63:519.39:42-0.410:000.16:375:18First Quarter17Wed
18Thu4:1410.34:548.910:43-0.111:000.56:365:19First Quarter18Thu
19Fri5:1710.16:018.611:470.16:345:20First Quarter19Fri
20Sat6:2310.07:118.612:030.712:540.16:335:22Waxing Gibbous20Sat
21Sun7:3210.08:188.91:090.81:590.06:315:23Waxing Gibbous21Sun
22Mon8:3610.19:179.22:130.62:59-0.26:305:24Waxing Gibbous22Mon
23Tue9:3310.310:079.63:120.33:52-0.56:285:25Full Moon23Tue
24Wed10:2310.410:539.84:050.04:38-0.66:275:27Full Moon24Wed
25Thu11:0910.411:3510.04:52-0.25:21-0.56:255:28Full Moon25Thu
26Fri11:5210.35:37-0.36:01-0.46:245:29Full Moon26Fri
27Sat12:1410.012:3310.06:19-0.36:40-0.16:225:30Waning Gibbous27Sat
28Sun12:529.91:149.77:01-0.17:190.26:215:32Waning Gibbous28Sun
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (8443970)

Common Questions About Boston, MA Tides

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What time does the tide turn (slack tide) in Boston, MA today?

Slack tide in Boston, MA is approximately 6:09 am — midway between the next high and low tide, when tidal current is weakest. This is the preferred window for boat crossings, underwater visibility, and fishing in areas with strong currents.

Is this week a spring tide or neap tide in Boston, MA?

Boston, MA is currently in a transitional phase. Tonight's moon is 27% illuminated. Spring tides (largest swings) occur near new and full moons; neap tides (smallest swings) occur near first and third quarter moons. Tidal ranges this week are shifting between spring and neap.

What datum are Boston, MA tide heights measured from?

Tide heights on this page are measured from Mean Lower Low Water (MLLW), the U.S. NOAA standard. A height of 0 ft represents the 19-year average of each day's lower low tide. Negative values indicate a "minus tide" — water levels below that long-term reference.

What factors can affect the tide predictions for Boston, MA?

Tide predictions for Boston, MA come from NOAA's harmonic analysis and are typically accurate within about ±10 minutes on timing and ±0.5 ft on height. Actual water levels can deviate further due to sustained winds, atmospheric pressure changes, river flow, and storm surge. During major weather events, be sure to check US Harbors weather pages for factors that could impact tidal predictions.

Which NOAA station provides tide data for Boston, MA?

Tide data for Boston, MA is sourced from NOAA Station #8443970. View the official NOAA station page at https://tidesandcurrents.noaa.gov/stationhome.html?id=8443970.

What is the moon phase in Boston, MA tonight?

Tonight the moon over Boston, MA is Waxing Crescent (27% illuminated). This places Boston, MA in a transitional tide cycle, so tidal ranges are shifting between spring and neap this week.

US Harbors Tidal Data

The data in our tide charts, tide tables, and tide graphs is provided by NOAA and others. These predictions are derived mathematically from numerous inputs, including data from historical tide stations and nearby locations where sensors are actively recording. As shown in the tide graph at the top of this page, “Predicted” tides (blue) are what forecasting models expect to happen. “Observed” tides (red) are those recorded by local sensors in real time, overlaid on the predictions for direct comparison. We display Observed water levels for a select group of harbors including Portland, Maine, where a physical sensor monitors water levels in real time.

LEARN MORE ABOUT OUR TIDE DATA