Tides Today & Tomorrow in Portsmouth, NH

TIDE TIMES for Saturday, August 15, 2026
The tide is currently falling in Portsmouth, NH.
Next low tide : in 31m at 8:09 pm (-0.2 ft)
Next high tide (tomorrow) : 2:28 am (8.9 ft)
Sunset today : 7:45 pm
Sunrise tomorrow : 5:49 am
Moon phase : Waxing Crescent (11% illuminated)
Tide Station Location : Station #8423745
Common Questions About Tides

Portsmouth, NH Tides - May 2095

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sun9:418.810:119.13:22-0.13:48-0.55:357:44Waning Crescent1Sun
2Mon10:389.011:019.64:19-0.74:40-0.75:347:45New Moon2Mon
3Tue11:329.211:509.95:13-1.25:30-0.85:337:46New Moon3Tue
4Wed12:259.26:05-1.56:19-0.75:317:47New Moon4Wed
5Thu12:3910.01:189.06:56-1.57:09-0.45:307:49New Moon5Thu
6Fri1:289.92:098.77:47-1.47:58-0.15:297:50Waxing Crescent6Fri
7Sat2:179.63:028.38:38-1.08:490.45:277:51Waxing Crescent7Sat
8Sun3:089.13:577.99:32-0.69:430.85:267:52Waxing Crescent8Sun
9Mon4:038.64:557.510:28-0.110:421.25:257:53First Quarter9Mon
10Tue5:028.15:547.311:270.411:431.55:247:54First Quarter10Tue
11Wed6:027.76:527.212:260.75:237:55First Quarter11Wed
12Thu7:047.57:497.212:461.61:240.95:227:56First Quarter12Thu
13Fri8:047.48:427.41:491.62:201.05:217:57Waxing Gibbous13Fri
14Sat9:007.49:297.72:481.43:091.05:197:58Waxing Gibbous14Sat
15Sun9:497.410:117.93:381.13:521.05:188:00Waxing Gibbous15Sun
16Mon10:357.510:498.24:220.84:300.95:178:01Waxing Gibbous16Mon
17Tue11:177.611:258.35:020.55:060.95:168:02Full Moon17Tue
18Wed11:577.65:390.35:410.95:168:03Full Moon18Wed
19Thu12:008.512:357.66:160.16:170.95:158:04Full Moon19Thu
20Fri12:358.61:137.66:520.06:541.05:148:05Full Moon20Fri
21Sat1:108.61:517.57:30-0.17:331.05:138:06Waning Gibbous21Sat
22Sun1:488.72:317.58:10-0.18:141.05:128:07Waning Gibbous22Sun
23Mon2:298.63:167.58:53-0.19:011.15:118:08Waning Gibbous23Mon
24Tue3:168.64:057.59:420.09:521.15:108:09Waning Gibbous24Tue
25Wed4:098.55:007.510:340.010:501.15:108:10Third Quarter25Wed
26Thu5:078.45:587.711:300.011:510.95:098:10Third Quarter26Thu
27Fri6:098.36:578.012:280.15:088:11Third Quarter27Fri
28Sat7:148.37:568.412:560.71:270.05:088:12Waning Crescent28Sat
29Sun8:208.38:538.92:020.32:26-0.15:078:13Waning Crescent29Sun
30Mon9:238.49:479.33:05-0.13:23-0.25:078:14Waning Crescent30Mon
31Tue10:218.510:399.64:03-0.64:16-0.25:068:15Waning Crescent31Tue
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 11:18 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 Portsmouth, NH?

Portsmouth, NH is currently in a spring phase. Tonight's moon is 11% 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 Crescent (11% 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