Tides Today & Tomorrow in Portsmouth, NH

TIDE TIMES for Tuesday, August 11, 2026
The tide is currently falling in Portsmouth, NH.
Next low tide : in 4h 28m at 4:29 am (-0.5 ft)
Next high tide : 10:47 am (7.9 ft)
Sunset today : 7:51 pm
Sunrise tomorrow : 5:44 am
Moon phase : New Moon (2% illuminated)
Tide Station Location : Station #8423745
Common Questions About Tides

Portsmouth, NH Tides - Jan 2089

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sat2:228.92:409.28:17-0.58:53-1.07:144:19Waning Gibbous1Sat
2Sun3:168.83:408.79:17-0.29:47-0.57:144:20Third Quarter2Sun
3Mon4:168.64:408.110:230.110:470.07:144:21Third Quarter3Mon
4Tue5:168.45:467.711:290.311:470.47:144:22Third Quarter4Tue
5Wed6:168.26:527.412:350.47:144:23Waning Crescent5Wed
6Thu7:168.17:527.312:470.71:350.47:144:24Waning Crescent6Thu
7Fri8:108.28:467.31:470.82:350.37:134:25Waning Crescent7Fri
8Sat8:588.29:347.32:410.83:230.17:134:26Waning Crescent8Sat
9Sun9:468.310:227.43:290.84:050.07:134:27Waning Crescent9Sun
10Mon10:288.411:047.54:110.74:47-0.17:134:28New Moon10Mon
11Tue11:048.411:407.64:470.75:23-0.17:124:29New Moon11Tue
12Wed11:408.45:230.65:59-0.17:124:30New Moon12Wed
13Thu12:167.612:168.45:590.66:29-0.17:114:31New Moon13Thu
14Fri12:527.612:528.36:350.67:05-0.17:114:33Waxing Crescent14Fri
15Sat1:227.71:288.17:110.67:350.07:104:34Waxing Crescent15Sat
16Sun1:587.72:048.07:530.68:110.17:104:35Waxing Crescent16Sun
17Mon2:347.72:467.88:350.68:530.37:094:36Waxing Crescent17Mon
18Tue3:167.83:347.69:230.69:410.47:094:37First Quarter18Tue
19Wed4:047.94:287.410:110.610:290.57:084:39First Quarter19Wed
20Thu4:528.05:227.311:110.511:230.57:074:40First Quarter20Thu
21Fri5:528.26:287.312:110.37:074:41Waxing Gibbous21Fri
22Sat6:528.57:347.512:230.51:170.07:064:43Waxing Gibbous22Sat
23Sun7:528.98:347.81:290.32:17-0.57:054:44Waxing Gibbous23Sun
24Mon8:529.39:348.32:29-0.13:17-1.07:044:45Waxing Gibbous24Mon
25Tue9:529.710:288.73:29-0.54:11-1.47:034:46Full Moon25Tue
26Wed10:4610.011:229.04:23-0.95:05-1.77:024:48Full Moon26Wed
27Thu11:4010.15:17-1.15:53-1.87:014:49Full Moon27Thu
28Fri12:169.212:3410.06:11-1.26:47-1.77:004:50Waning Gibbous28Fri
29Sat1:049.31:229.67:05-1.17:35-1.46:594:52Waning Gibbous29Sat
30Sun1:589.12:169.17:59-0.88:23-0.96:584:53Waning Gibbous30Sun
31Mon2:468.93:168.58:53-0.59:17-0.46:574:54Third Quarter31Mon
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 7:38 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 2% 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 New Moon (2% 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