Nidelva River — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in the Nidelva River, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in the Nidelva River today is 3.8°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
❌ As of today, the minimum water temperature ranges less than 41°F (5°C). Such water is extremely cold and not recommended for swimming without proper preparation. In these conditions, the risk of hypothermia is very high, and prolonged exposure to the water can be hazardous to your health. If you decide to swim, it is important to have the appropriate gear, such as a wetsuit. Typically, only experienced swimmers or those who practice winter swimming venture into such waters. It is important to note that these swimming tips and recommendations apply only in good weather. When the air temperature is below 68°F (20°C), and sometimes even below 77°F (25°C), swimming can be unpleasant even with relatively high water temperatures.
Water Temperature Chart Over the Last 30 Days
Table of Daily Sea Temperature Data
| Date | Current | Average | Forecast |
|---|---|---|---|
| APR 11 | 3.8°C | 7.0°C | |
| APR 12 | 3.8°C | 7.0°C | |
| APR 13 | 3.7°C | 7.0°C | |
| APR 14 | 3.7°C | 7.0°C | |
| APR 15 | 3.7°C | 7.0°C | |
| APR 16 | 3.8°C | 7.0°C | |
| APR 17 | 3.8°C | 7.0°C | |
| APR 18 | 3.8°C | 7.0°C | |
| APR 19 | 7.0°C | 4.0°C | |
| APR 20 | 7.0°C | 4.1°C | |
| APR 21 | 7.0°C | 4.3°C | |
| APR 22 | 7.0°C | 4.4°C | |
| APR 23 | 7.0°C | 4.6°C | |
| APR 24 | 7.0°C | 4.8°C | |
| APR 25 | 7.0°C | 4.9°C |
* Current - Actual water temperature value
** Average - Average water temperature on this day in recent years
*** Forecast - Our water temperature forecast
Actual nearshore water temperatures may fluctuate by several degrees from the reported values, especially following heavy rainfall or extended periods of strong winds. Certain wind patterns can cause colder, deeper waters to rise and replace the sun-warmed surface water, leading to noticeable variations.
Our forecast is based on a proprietary mathematical model that considers real-time water temperature changes, historical trends, key weather patterns, wind strength and direction, and air temperature specific to each region. Additionally, we incorporate data from other resorts to enhance accuracy.
Monthly Water Temperature Range (Min, Max & Average)
| Month | Min | Avg | Max |
|---|---|---|---|
| January | 0°C | 2°C | 5°C |
| February | 0°C | 2°C | 5°C |
| March | 0°C | 3°C | 6°C |
| April | 3°C | 7°C | 9°C |
| May | 7°C | 11°C | 16°C |
| June | 11°C | 16°C | 20°C |
| July | 13°C | 18°C | 22°C |
| August | 12°C | 17°C | 21°C |
| September | 9°C | 14°C | 18°C |
| October | 5°C | 9°C | 11°C |
| November | 2°C | 6°C | 9°C |
| December | 0°C | 3°C | 6°C |
Nidelva River: Water Temperature by Location
Nidelva River: Weather Forecast
April 19
April 20
April 21
April 22
Location & Local Information
Source Confluence of Nisserelva and Fyresdalsåna rivers
• location Haugsjåsund, Nissedal, Telemark
• coordinates 58.9406°N 08.5011°E
• elevation 160 metres (520 ft)
Mouth Skaggerak
• location Arendal, Agder
• coordinates 58.4349°N 08.7137°E
• elevation 0 metres (0 ft)
Length 221.7 km (137.8 mi)
Nidelva in Agder County typically shows marked seasonal variation in water temperature. In winter the river is cold, often close to freezing with surface temperatures around 0–4 °C (32–39 °F) in exposed stretches. During spring, as snowmelt and rain increase flow, temperatures usually rise to roughly 2–12 °C (36–54 °F) depending on location and weather. Summer brings the warmest conditions in sheltered, slow-moving parts of the river and near the estuary, where water commonly reaches about 12–22 °C (54–72 °F) on warm days; during heatwaves shallow bays can be a few degrees warmer. In autumn the river cools again, with typical ranges around 4–10 °C (39–50 °F) before winter sets in.
Swimming in Nidelva is generally possible in many locations and is a popular local activity in summer, but it is not universally permitted everywhere because of safety and management reasons. Water quality is usually good in many stretches, yet can deteriorate after heavy rainfall or near urban runoff, and some sections are affected by strong currents, submerged obstacles or regulated flows from hydro installations. Municipal rules, private property and local signage can restrict access, so swimmers are advised to choose known safe spots, check current conditions and be cautious of cold shock and changing currents even on warm days.