Tides Today & Tomorrow in Portsmouth, NH

TIDE TIMES for Tuesday, August 11, 2026
The tide is currently falling in Portsmouth, NH.
Next low tide (tomorrow) : in 5h 45m at 5:24 am (-0.8 ft)
Next high tide (tomorrow) : 11:43 am (8.2 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 1968

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Mon11:529.55:310.06:16-1.17:144:18New Moon1Mon
2Tue12:378.112:439.36:230.17:05-0.87:144:19Waxing Crescent2Tue
3Wed1:268.01:348.97:140.37:54-0.57:144:19Waxing Crescent3Wed
4Thu2:167.82:248.48:050.58:42-0.17:144:20Waxing Crescent4Thu
5Fri3:067.73:177.98:590.89:310.37:144:21First Quarter5Fri
6Sat3:567.54:117.49:551.010:200.77:144:22First Quarter6Sat
7Sun4:467.45:077.010:521.211:091.17:144:23First Quarter7Sun
8Mon5:377.46:056.711:511.27:144:24First Quarter8Mon
9Tue6:287.47:046.512:001.412:501.27:144:25Waxing Gibbous9Tue
10Wed7:217.58:026.512:541.61:481.07:134:26Waxing Gibbous10Wed
11Thu8:117.68:546.61:481.62:390.87:134:28Waxing Gibbous11Thu
12Fri8:587.89:406.82:371.53:250.57:134:29Waxing Gibbous12Fri
13Sat9:418.010:237.03:211.44:060.37:124:30Waxing Gibbous13Sat
14Sun10:238.311:047.14:021.24:460.17:124:31Full Moon14Sun
15Mon11:038.511:437.34:420.95:24-0.27:124:32Full Moon15Mon
16Tue11:428.75:210.76:01-0.37:114:33Full Moon16Tue
17Wed12:207.512:218.86:020.56:39-0.57:114:34Waning Gibbous17Wed
18Thu12:587.71:028.86:440.37:18-0.67:104:36Waning Gibbous18Thu
19Fri1:377.91:458.77:280.28:00-0.57:094:37Waning Gibbous19Fri
20Sat2:198.12:328.58:170.18:44-0.47:094:38Waning Gibbous20Sat
21Sun3:068.33:258.19:090.19:33-0.17:084:39Third Quarter21Sun
22Mon3:568.44:237.810:070.110:260.17:074:41Third Quarter22Mon
23Tue4:518.45:267.411:080.111:230.47:074:42Third Quarter23Tue
24Wed5:508.46:357.212:140.17:064:43Waning Crescent24Wed
25Thu6:548.57:457.212:260.61:24-0.17:054:45Waning Crescent25Thu
26Fri8:008.78:517.41:330.72:30-0.37:044:46Waning Crescent26Fri
27Sat9:028.99:507.62:370.63:30-0.57:034:47Waning Crescent27Sat
28Sun9:599.110:447.83:360.44:24-0.77:024:48New Moon28Sun
29Mon10:529.211:347.94:300.25:15-0.87:014:50New Moon29Mon
30Tue11:429.15:210.16:02-0.87:004:51New Moon30Tue
31Wed12:208.012:299.06:090.06:45-0.76:594:52Waxing Crescent31Wed
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 8:33 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