Nearby Harbors
43.0783’ N, 70.7517’ W

Portsmouth, NH

61°
H 63°
L 46°
NE
14mph
Low tide
3:45 pm
Photo Credits

Tides Today & Tomorrow in Portsmouth, NH

TIDE TIMES for Wednesday, September 23, 2026
The tide is currently falling in Portsmouth, NH.
Next low tide : in 3h 57m at 3:45 pm (1.2 ft)
Next high tide : 10:04 pm (8.0 ft)
Sunset today : 6:38 pm
Sunrise tomorrow : 6:31 am
Moon phase : Waxing Gibbous (90% illuminated)
Tide Station Location : Station #8423745
Common Questions About Tides

Featured Local Businesses

Maritime Boats by Chislett Marine

Maritime Boats
Marine Supplies

Hamilton Marine - Kittery, ME
An aerial view of Safe Harbor Kittery Point

Safe Harbor Kittery Point
Great Bay Marine

Great Bay Marine

Portsmouth, NH Tides - Dec 2171

Print this Tide Chart

We're sorry. There is no tidal information for this month. Please check back later.

© 2026 US Harbors LLC All rights reserved

The US Harbors tide chart design is protected by copyright. It may be printed for personal use only.
Any commercial use, modification, redistribution, or repackaging without written permission is strictly prohibited.

Common Questions About Portsmouth, NH Tides

Collapse All
Is this week a spring tide or neap tide in Portsmouth, NH?

Portsmouth, NH is currently in a spring phase. Tonight's moon is 90% 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 (90% 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

Coastal Stories See All

Sablefish farmed in net pens at NOAA's Northwest Fisheries Science Center. Credit: Megan Ewald for NOAA Fisheries.

Managing Genetic Risk in Offshore Aquaculture

By fisheries.noaa.gov, fisheries.noaa.gov. Aquaculture can sustainably produce seafood to complement wild-caught fisheries. However, like all… More

FishingFoodScience

Deep-sea sponges and other invertebrates in a collection basket during a bottom trawl survey. Credit: NOAA Fisheries

Nine Species of Deep-Sea Sponges Discovered in Alaska

By fisheries.noaa.gov, fisheries.noaa.gov. Scientists have discovered nine new species of sponges in the Gulf of… More

Ocean Science

Sugar Creek flows over a dam initially created with beaver dam analogues to help improve habitat for coho salmon and other wildlife. Photo courtesy of Scott River Watershed Council.

Start-Up Beaver Dams Transform Parched California Creeks into Salmon Havens, New Research Finds

By fisheries.noaa.gov, fisheries.noaa.gov. Battered by early gold mining and diminished by logging and diversions,the lower… More

Coastal News

Image Credits: Flickr.com.

Concrete Ships Hiding in Plain Sight: The Forgotten Breakwaters of America's Harbors

By Jordan Hanssen, best4boats. There's a good chance a concrete ship is lurking in your… More

Maritime History

Image Credits: Flickr.com.

Is Offshore Construction Noise Stressing New England's Lobsters? WHOI Scientists Want to Know

By Kiran Johnson, whoi.edu. As offshore wind farms multiply along the New England coast, a… More

Coastal LifeOcean AwarenessOcean Science

The future of fisheries-independent surveys will include traditional capture-based surveys as well as advanced technology such as acoustic, optical, and molecular tools deployed from survey vessels, uncrewed vehicles, and moored to the seafloor. Credit: NOAA Fisheries/Su Kim

Charting the Future of Fisheries-Independent Surveys

By fisheries.noaa.gov, fisheries.noaa.gov. Fisheries-independent surveys operate on dedicated survey vessels and are the foundation of… More

Ocean Science

Coastally-trapped Kelvin waves, a signature of El Niño, traveled north along the West Coast during the 1997/1998 El Niño, as shown in a map of sea surface height anomalies. Darker reds show sea levels higher than normal, while darker blues show heights below normal. Scientists are now watching for similar waves to move up the West Coast this fall. Credit: Dillon Amaya/North Carolina State University

Ocean Indicators We’re Tracking for El Niño’s Arrival on the West Coast

By fisheries.noaa.gov, fisheries.noaa.gov. Has El Niño reached the West Coast? You might think it has.… More

Coastal NewsExtreme WeatherOcean ScienceWeather & Tides

Docked fishing boats at Yaquina Bay, Newport, Oregon. Credit: iStock

Advancing Agency-Level Reforms to Restore American Seafood Competitiveness

By fisheries.noaa.gov, fisheries.noaa.gov. Over the past year, I have met with fishermen, processors, coastal community… More

Coastal NewsFishingFood

Image Credits: Wikimedia commons.

Coral IVF: How Scientists Are Breeding Heat-Resistant Reefs for Florida's Future

By Dawn Anderson, best4boats.com. The reefs that protect South Florida's coastlines, harbors, and marinas are… More

Ocean Science

Your Privacy Choices