Frequently Asked Questions

Our website is part of the global SeaTemperature Global Project, which supports 30 websites about water temperature in different languages. You are currently on the main English-language website, which serves as the primary site within the global project structure. All the latest updates are released here first.

Our website collects, analyzes, and provides users with information about water temperatures in seas and oceans worldwide, as well as in lakes and rivers in some European countries (Germany, Austria, Switzerland, Luxembourg, Belgium, the Netherlands, France, Poland, Ukraine, Italy, Hungary, Russia) and North America (primarily the USA and partially Canada).

We provide sea surface temperature data for all regions of the world. Our database includes nearly 12,000 coastal cities and resorts from all countries worldwide.

We provide information for more than 12,000 locations worldwide. Our database includes not only large cities but also small villages, resorts, and even individual beaches.

Yes, we collect, study, and systematize data on most rivers in Europe and North America. The list of countries, rivers, and lakes is constantly expanding. For rivers, we analyze temperature data at various points along their entire course.

Our website is updated continuously. We monitor water temperatures in seas, oceans, rivers, and lakes 24/7.

Yes, of course. We have a search function that allows you to quickly find the location you need. If you have specific search requirements, you can use the menu to select the country, region, and find the desired location in the list.

We collect information from multiple sources, including both public and subscription-based data. Major data providers include NOAA (National Oceanic and Atmospheric Administration), USGS (United States Geological Survey), Copernicus (European Environmental Agency), as well as various government and public organizations that conduct research and collect water temperature data from different locations worldwide. We also use weather services through APIs such as worldweatheronline.com and others. In some cases, we utilize local data sources. This vast amount of information is then processed and presented in a user-friendly format.

The collected data comes from specialized buoys equipped with measurement instruments, as well as satellite imagery, which provides information on water temperatures in seas, oceans, and inland bodies of water. All collected data is analyzed, checked for accuracy against historical records, and used to calculate water temperature for each location displayed to users.

In most cases, our data is quite accurate. We strive to provide up-to-date information, but we cannot guarantee 100% accuracy or completeness. Water temperature can change due to local conditions, sometimes even within short distances.

The website is not intended for use in situations involving health, safety, or property risks (e.g., professional fishing, navigation, sports events).

We offer a 7-day water temperature forecast for each location. To generate these forecasts, we use various parameters, primarily: current temperature, historical data, and weather forecasts for the coming days. Users familiar with our website will find these forecasts very useful.

Yes, of course. Our global system contains a large amount of historical water temperature data from previous years. For user convenience, we display historical water temperature data for each location, broken down by month.

Water temperature considered comfortable for swimming varies depending on individual preferences, but generally:

• 20-22°C (68-72°F) – Cool water, suitable for active swimming.

• 23-25°C (73-77°F) – Comfortable for most people, good for water sports.

• 26-30°C (78-86°F) – Warm water, ideal for long swims or relaxing in the water.

• Above 30°C (86°F+) — Considered hot, and prolonged exposure may be uncomfortable.

Water temperature is usually measured using thermometers such as:

• Digital thermometers — Provide precise readings with electronic sensors.

• Mercury thermometers — Traditional but less commonly used due to fragility and mercury spill risks.

• Infrared thermometers – Measure surface water temperature without direct contact.

Water temperature is displayed in degrees Celsius (°C) or degrees Fahrenheit (°F) depending on the region.

Water temperature changes due to various factors:

• Geographical location – Equatorial regions have warmer waters, while polar regions are much colder.

• Season – Water temperature fluctuates with the seasons: it is higher in summer and lower in winter.

• Ocean currents – Warm or cold currents can significantly impact local water temperatures.

• Depth – Deeper waters maintain more stable, cooler temperatures.

• Wind – Strong winds can cool surface waters, especially in stormy regions.

Water temperature has a significant impact on marine ecosystems:

• Effects on fish and marine life – Each species has an optimal temperature range. Extreme temperatures can disrupt reproduction, migration, and feeding patterns.

• Coral reefs — Corals are highly sensitive to temperature changes. Water above 30°C (86°F) can cause coral bleaching, damaging entire ecosystems.

• Ocean productivity – Temperature affects phytoplankton growth, which forms the base of the marine food chain.