Tides Today & Tomorrow in Merrimack River Entrance, MA

TIDE TIMES for Tuesday, July 21, 2026
The tide is currently rising in Merrimack River Entrance, MA.
Next low tide (tomorrow) : 12:19 am (0.7 ft)
Next high tide : in 1h 50m at 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 - Sep 1978

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Fri11:277.711:428.45:210.55:320.86:077:18New Moon1Fri
2Sat12:067.96:000.36:130.66:087:17New Moon2Sat
3Sun12:228.512:448.16:380.36:520.46:097:15New Moon3Sun
4Mon1:018.51:228.37:150.27:320.36:107:13Waxing Crescent4Mon
5Tue1:408.52:018.57:530.28:140.26:117:11Waxing Crescent5Tue
6Wed2:218.42:428.68:330.28:580.16:137:10Waxing Crescent6Wed
7Thu3:058.33:268.79:160.39:460.16:147:08Waxing Crescent7Thu
8Fri3:548.14:168.710:030.510:390.16:157:06First Quarter8Fri
9Sat4:488.05:108.710:560.611:360.26:167:04First Quarter9Sat
10Sun5:467.86:098.811:530.76:177:03First Quarter10Sun
11Mon6:477.87:118.912:360.112:540.76:187:01First Quarter11Mon
12Tue7:507.98:149.01:390.01:570.56:196:59Waxing Gibbous12Tue
13Wed8:518.29:159.32:41-0.22:590.26:206:57Waxing Gibbous13Wed
14Thu9:498.610:129.53:39-0.53:58-0.16:216:55Waxing Gibbous14Thu
15Fri10:439.011:069.64:33-0.74:53-0.56:226:54Full Moon15Fri
16Sat11:349.311:589.75:24-0.95:46-0.86:236:52Full Moon16Sat
17Sun12:239.56:13-0.96:36-0.96:246:50Full Moon17Sun
18Mon12:479.61:109.67:00-0.87:25-0.96:266:48Waning Gibbous18Mon
19Tue1:359.31:569.57:46-0.68:13-0.76:276:46Waning Gibbous19Tue
20Wed2:229.02:429.38:31-0.29:01-0.46:286:45Waning Gibbous20Wed
21Thu3:108.53:309.09:180.29:50-0.16:296:43Waning Gibbous21Thu
22Fri4:008.14:198.610:070.610:420.36:306:41Third Quarter22Fri
23Sat4:527.75:128.310:591.011:360.66:316:39Third Quarter23Sat
24Sun5:467.46:078.011:531.36:326:38Third Quarter24Sun
25Mon6:437.27:037.812:320.812:501.46:336:36Third Quarter25Mon
26Tue7:407.28:007.81:301.01:481.46:346:34Waning Crescent26Tue
27Wed8:357.38:557.92:260.92:431.36:356:32Waning Crescent27Wed
28Thu9:267.59:448.03:170.83:341.16:366:30Waning Crescent28Thu
29Fri10:117.710:308.24:030.74:210.86:386:29Waning Crescent29Fri
30Sat10:538.011:138.34:460.55:040.66:396:27New Moon30Sat
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 9:08 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