Tides Today & Tomorrow in Merrimack River Entrance, MA

TIDE TIMES for Tuesday, July 21, 2026
The tide is currently falling in Merrimack River Entrance, MA.
Next low tide : in 3h 29m at 11:40 am (0.6 ft)
Next high tide : 5:57 pm (8.4 ft)
Sunset today : 8:15 pm
Sunrise tomorrow : 5:23 am
Moon phase : First Quarter (52% illuminated)
Tide Station Location : Station #8440452
Common Questions About Tides

Merrimack River Entrance, MA Tides - Nov 1978

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Wed11:229.211:518.55:120.25:43-0.56:174:36New Moon1Wed
2Thu12:059.55:550.16:28-0.76:184:35Waxing Crescent2Thu
3Fri12:368.512:509.66:390.17:14-0.86:194:33Waxing Crescent3Fri
4Sat1:248.51:399.67:270.18:05-0.86:214:32Waxing Crescent4Sat
5Sun2:158.42:329.48:190.28:59-0.76:224:31Waxing Crescent5Sun
6Mon3:118.43:299.29:160.39:56-0.56:234:30First Quarter6Mon
7Tue4:108.34:319.010:180.410:56-0.46:244:29First Quarter7Tue
8Wed5:118.45:348.811:220.411:57-0.26:264:27First Quarter8Wed
9Thu6:138.56:388.612:270.36:274:26Waxing Gibbous9Thu
10Fri7:148.77:418.612:58-0.21:310.16:284:25Waxing Gibbous10Fri
11Sat8:119.08:398.61:57-0.22:30-0.26:294:24Waxing Gibbous11Sat
12Sun9:049.29:338.52:51-0.23:25-0.46:314:23Waxing Gibbous12Sun
13Mon9:539.310:228.53:41-0.14:15-0.66:324:22Full Moon13Mon
14Tue10:399.311:098.34:270.05:02-0.66:334:21Full Moon14Tue
15Wed11:229.311:538.25:120.25:46-0.56:354:20Full Moon15Wed
16Thu12:049.15:550.46:28-0.46:364:19Full Moon16Thu
17Fri12:358.012:468.96:360.67:09-0.26:374:18Waning Gibbous17Fri
18Sat1:187.81:288.77:190.87:520.06:384:18Waning Gibbous18Sat
19Sun2:017.62:128.48:031.08:370.26:404:17Waning Gibbous19Sun
20Mon2:477.52:598.18:501.29:240.56:414:16Waning Gibbous20Mon
21Tue3:367.43:497.99:411.410:140.66:424:15Third Quarter21Tue
22Wed4:277.34:437.610:351.411:050.86:434:15Third Quarter22Wed
23Thu5:207.45:387.511:301.411:580.96:444:14Third Quarter23Thu
24Fri6:137.56:337.412:261.36:464:13Third Quarter24Fri
25Sat7:057.77:287.512:500.91:211.06:474:13Waning Crescent25Sat
26Sun7:548.18:197.61:400.82:130.76:484:12Waning Crescent26Sun
27Mon8:418.49:087.82:280.73:010.36:494:12Waning Crescent27Mon
28Tue9:268.89:558.03:130.53:48-0.26:504:11New Moon28Tue
29Wed10:109.210:428.23:580.34:34-0.66:514:11New Moon29Wed
30Thu10:569.511:298.44:440.15:20-0.96:524:10New Moon30Thu
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (8440452)

Common Questions About Merrimack River Entrance, MA Tides

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What time does the tide turn (slack tide) in Merrimack River Entrance, MA today?

Slack tide in Merrimack River Entrance, MA is approximately 2:48 pm — 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 Merrimack River Entrance, MA?

Merrimack River Entrance, MA is currently in a neap phase. Tonight's moon is 52% 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 near their weekly minimum.

What datum are Merrimack River Entrance, 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 Merrimack River Entrance, MA?

Tide predictions for Merrimack River Entrance, 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 Merrimack River Entrance, MA?

Tide data for Merrimack River Entrance, MA is sourced from NOAA Station #8440452. View the official NOAA station page at https://tidesandcurrents.noaa.gov/stationhome.html?id=8440452.

What is the moon phase in Merrimack River Entrance, MA tonight?

Tonight the moon over Merrimack River Entrance, MA is First Quarter (52% illuminated). This places Merrimack River Entrance, MA in a neap tide cycle, so tidal ranges are near their weekly minimum 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