Tides Today & Tomorrow in Portsmouth, NH

TIDE TIMES for Sunday, August 23, 2026
The tide is currently rising in Portsmouth, NH.
Next low tide : 2:42 pm (1.8 ft)
Next high tide : in 4h 38m at 8:57 am (6.6 ft)
Sunset today : 7:33 pm
Sunrise tomorrow : 5:57 am
Moon phase : Waxing Gibbous (81% illuminated)
Tide Station Location : Station #8423745
Common Questions About Tides

Portsmouth, NH Tides - Nov 1952

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sat10:179.510:528.73:57-0.24:33-1.06:174:35Full Moon1Sat
2Sun11:039.511:428.54:44-0.15:21-1.06:194:34Full Moon2Sun
3Mon11:499.45:300.16:09-0.96:204:32Full Moon3Mon
4Tue12:298.212:349.16:160.46:55-0.66:214:31Waning Gibbous4Tue
5Wed1:167.91:198.87:020.77:43-0.26:234:30Waning Gibbous5Wed
6Thu2:047.62:078.47:491.18:320.36:244:29Waning Gibbous6Thu
7Fri2:557.22:598.08:391.49:240.76:254:27Third Quarter7Fri
8Sat3:497.03:547.69:331.610:180.96:264:26Third Quarter8Sat
9Sun4:436.94:517.410:311.811:121.16:284:25Third Quarter9Sun
10Mon5:376.95:487.211:301.86:294:24Third Quarter10Mon
11Tue6:307.16:457.212:041.212:291.76:304:23Third Quarter11Tue
12Wed7:197.37:397.212:551.21:241.46:324:22Waning Crescent12Wed
13Thu8:047.68:287.31:421.12:131.06:334:21Waning Crescent13Thu
14Fri8:458.09:127.42:241.02:570.66:344:20Waning Crescent14Fri
15Sat9:228.39:547.63:030.93:370.36:354:19New Moon15Sat
16Sun10:008.610:367.73:410.84:170.06:374:18New Moon16Sun
17Mon10:388.811:177.74:200.74:57-0.36:384:17New Moon17Mon
18Tue11:189.011:597.85:000.65:39-0.46:394:16New Moon18Tue
19Wed12:019.15:430.66:24-0.56:404:16Waxing Crescent19Wed
20Thu12:447.712:479.16:290.67:11-0.56:424:15Waxing Crescent20Thu
21Fri1:317.71:379.07:180.68:02-0.46:434:14Waxing Crescent21Fri
22Sat2:247.62:328.88:120.78:57-0.26:444:13Waxing Crescent22Sat
23Sun3:227.63:338.59:120.89:55-0.16:454:13First Quarter23Sun
24Mon4:237.84:388.310:170.810:550.16:474:12First Quarter24Mon
25Tue5:258.05:458.111:240.711:560.26:484:12First Quarter25Tue
26Wed6:268.26:528.012:330.46:494:11Waxing Gibbous26Wed
27Thu7:248.67:578.012:570.21:380.16:504:11Waxing Gibbous27Thu
28Fri8:208.98:558.01:550.32:38-0.36:514:10Waxing Gibbous28Fri
29Sat9:119.19:498.12:490.33:31-0.66:524:10Full Moon29Sat
30Sun9:599.210:408.03:390.34:21-0.76:534:09Full Moon30Sun
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (8423745)

Common Questions About Portsmouth, NH Tides

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What time does the tide turn (slack tide) in Portsmouth, NH today?

Slack tide in Portsmouth, NH is approximately 11:49 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 Portsmouth, NH?

Portsmouth, NH is currently in a spring phase. Tonight's moon is 81% 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 maximum.

What datum are Portsmouth, NH 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 Portsmouth, NH?

Tide predictions for Portsmouth, NH 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 Portsmouth, NH?

Tide data for Portsmouth, NH is sourced from NOAA Station #8423745. View the official NOAA station page at https://tidesandcurrents.noaa.gov/stationhome.html?id=8423745.

What is the moon phase in Portsmouth, NH tonight?

Tonight the moon over Portsmouth, NH is Waxing Gibbous (81% illuminated). This places Portsmouth, NH in a spring tide cycle, so tidal ranges are near their weekly maximum 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