Tides Today & Tomorrow in Portsmouth, NH

TIDE TIMES for Sunday, June 21, 2026
The tide is currently falling in Portsmouth, NH.
Next low tide : in 4h 27m at 11:52 pm (0.7 ft)
Next high tide (tomorrow) : 6:09 am (7.9 ft)
Sunset today : 8:26 pm
Sunrise tomorrow : 5:03 am
Moon phase : First Quarter (48% illuminated)
Tide Station Location : Station #8423745
Common Questions About Tides

Portsmouth, NH Tides - Dec 2029

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sat6:398.57:117.912:130.312:530.16:554:09Waning Crescent1Sat
2Sun7:369.08:138.11:110.11:55-0.46:564:08Waning Crescent2Sun
3Mon8:329.49:128.42:08-0.12:53-0.96:574:08Waning Crescent3Mon
4Tue9:269.810:088.53:04-0.33:48-1.36:584:08New Moon4Tue
5Wed10:1910.011:038.63:58-0.44:42-1.56:594:08New Moon5Wed
6Thu11:1310.111:578.64:51-0.55:35-1.57:004:08New Moon6Thu
7Fri12:069.95:45-0.46:28-1.47:014:08Waxing Crescent7Fri
8Sat12:498.512:599.66:38-0.27:20-1.17:024:08Waxing Crescent8Sat
9Sun1:428.41:529.27:320.08:12-0.77:034:08Waxing Crescent9Sun
10Mon2:368.22:488.78:280.49:06-0.27:034:08Waxing Crescent10Mon
11Tue3:327.93:468.19:270.710:000.27:044:08First Quarter11Tue
12Wed4:277.84:457.610:280.910:540.67:054:08First Quarter12Wed
13Thu5:227.75:457.211:291.011:491.07:064:08First Quarter13Thu
14Fri6:167.76:457.012:311.07:074:08First Quarter14Fri
15Sat7:097.77:436.912:441.21:300.97:074:08Waxing Gibbous15Sat
16Sun8:007.88:366.91:371.32:240.87:084:09Waxing Gibbous16Sun
17Mon8:467.99:247.02:261.33:110.57:094:09Waxing Gibbous17Mon
18Tue9:298.110:087.13:101.33:530.47:094:09Waxing Gibbous18Tue
19Wed10:108.210:497.23:511.24:320.27:104:10Full Moon19Wed
20Thu10:498.311:287.34:291.15:100.17:104:10Full Moon20Thu
21Fri11:268.45:071.05:460.07:114:11Full Moon21Fri
22Sat12:067.412:038.55:440.96:21-0.17:114:11Full Moon22Sat
23Sun12:427.512:418.56:230.86:58-0.27:124:12Waning Gibbous23Sun
24Mon1:187.61:208.57:030.77:36-0.27:124:12Waning Gibbous24Mon
25Tue1:577.72:028.47:470.68:18-0.27:134:13Waning Gibbous25Tue
26Wed2:397.92:508.28:350.59:03-0.17:134:14Third Quarter26Wed
27Thu3:268.03:438.09:280.59:530.07:134:14Third Quarter27Thu
28Fri4:178.24:417.810:260.310:460.27:134:15Third Quarter28Fri
29Sat5:128.45:437.611:270.211:430.37:144:16Third Quarter29Sat
30Sun6:108.66:507.612:310.07:144:17Waning Crescent30Sun
31Mon7:128.97:577.712:450.31:37-0.37:144:17Waning Crescent31Mon
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 3:00 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 neap phase. Tonight's moon is 48% 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 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 First Quarter (48% illuminated). This places Portsmouth, NH 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