Norsjø Lake — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Norsjø Lake, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Norsjø Lake today is 13°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
⚠️ As of today, the minimum water temperature ranges from 54°F (12°C) to 60°F (15°C). The water is significantly warmer, and swimming becomes possible for most people. However, caution may still be required for prolonged stays in the water, as extended exposure can cause discomfort. This is a suitable temperature range for short swims and for those accustomed to cooler water. For more comfortable swimming, it is recommended to use proper gear. 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 |
|---|---|---|---|
| SEP 14 | 13.6°C | 18.0°C | |
| SEP 15 | 13.9°C | 18.0°C | |
| SEP 16 | 13.7°C | 18.0°C | |
| SEP 17 | 13.7°C | 18.0°C | |
| SEP 18 | 13.6°C | 18.0°C | |
| SEP 19 | 13.3°C | 18.0°C | |
| SEP 20 | 12.6°C | 18.0°C | |
| SEP 21 | 13.0°C | 18.0°C | |
| SEP 22 | 18.0°C | 13.3°C | |
| SEP 23 | 18.0°C | 13.5°C | |
| SEP 24 | 18.0°C | 13.8°C | |
| SEP 25 | 18.0°C | 14.0°C | |
| SEP 26 | 18.0°C | 14.3°C | |
| SEP 27 | 18.0°C | 14.5°C | |
| SEP 28 | 18.0°C | 14.8°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 | 3°C | 6°C |
| February | 0°C | 3°C | 6°C |
| March | 0°C | 4°C | 7°C |
| April | 2°C | 7°C | 11°C |
| May | 7°C | 12°C | 18°C |
| June | 11°C | 18°C | 24°C |
| July | 17°C | 22°C | 27°C |
| August | 16°C | 22°C | 27°C |
| September | 12°C | 18°C | 23°C |
| October | 7°C | 11°C | 14°C |
| November | 3°C | 7°C | 10°C |
| December | 0°C | 4°C | 7°C |
Norsjø Lake: Water Temperature by Location
Norsjø Lake: Weather Forecast
September 21
September 22
September 23
September 24
September 25
September 26
Location & Local Information
Norsjø is a large inland lake in Telemark County (Norsjø in Norwegian) that shows clear seasonal variation in surface water temperature. In spring (April–May) surface temperatures commonly range from about 2–8 °C (36–46 °F) as the lake warms after ice melt. Summer months (June–August) typically bring the warmest conditions, with surface temperatures often between 15–22 °C (59–72 °F) and occasional spots reaching the low 20s °C (around 73 °F) in warm, calm weather. During autumn (September–October) temperatures fall back toward roughly 8–15 °C (46–59 °F). In winter the lake cools to near freezing and parts may ice over, with surface temperatures around 0–4 °C (32–39 °F) where ice or cold water persists.
Swimming in Norsjø is generally allowed and common at public beaches and informal bathing spots because the shoreline is public and municipal authorities permit recreational use. Local water quality is regularly monitored, so swimming is feasible when no advisories are in effect; however, conditions can vary with runoff, algae blooms, or boat traffic related to the Telemark Canal connections. Bathers should take standard precautions for cold-water exposure, be aware of boating areas and currents, and follow posted guidance from local authorities to ensure safe swimming.