Semily — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Semily, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Semily today is 9.9°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
❌ As of today, the minimum water temperature ranges from 47°F (8°C) to 50°F (10°C). This is still cool water, suitable only for experienced swimmers or those accustomed to cold water. Swimming in such conditions is possible, but not recommended for prolonged periods. Extra caution should be taken during extended exposure, as the cold water can cause heat loss and lead to hypothermia. For added comfort, special clothing can be used. 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 |
|---|---|---|---|
| OCT 5 | 11.0°C | 11.5°C | |
| OCT 6 | 10.9°C | 11.5°C | |
| OCT 7 | 10.8°C | 11.5°C | |
| OCT 8 | 10.4°C | 11.5°C | |
| OCT 9 | 10.1°C | 11.5°C | |
| OCT 10 | 10.5°C | 11.5°C | |
| OCT 11 | 10.8°C | 11.5°C | |
| OCT 12 | 10.5°C | 11.5°C | |
| OCT 13 | 11.5°C | 10.0°C | |
| OCT 14 | 11.5°C | 10.1°C | |
| OCT 15 | 11.5°C | 10.1°C | |
| OCT 16 | 11.5°C | 10.2°C | |
| OCT 17 | 11.5°C | 10.3°C | |
| OCT 18 | 11.5°C | 10.4°C | |
| OCT 19 | 11.5°C | 10.5°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 | 1°C | 5°C | 9°C |
| February | 1°C | 5°C | 9°C |
| March | 3°C | 7°C | 11°C |
| April | 4°C | 10°C | 16°C |
| May | 7°C | 14°C | 21°C |
| June | 11°C | 17°C | 22°C |
| July | 14°C | 19°C | 24°C |
| August | 13°C | 18°C | 23°C |
| September | 10°C | 15°C | 19°C |
| October | 7°C | 12°C | 16°C |
| November | 2°C | 9°C | 16°C |
| December | 1°C | 5°C | 8°C |
Semily: Weather Forecast
October 13
October 14
October 15
October 16
October 17
Location & Local Information
In Semily, the Jizera River flows through a picturesque setting surrounded by rolling hills and forested areas. Because the river is fed by mountain streams, its water remains relatively cool throughout the year. In late spring, temperatures usually range around 14–16 °C, while in July and August they can rise to 17–19 °C on warmer days. This makes swimming refreshing, though the cooler temperature is better suited for short dips rather than long, leisurely swims.
Swimming directly in the Jizera within Semily is limited, as the urban riverbanks are not specifically developed for bathing. However, there are some calmer and shallower sections where locals occasionally enjoy a brief dip. The gentle current in these areas allows for safe wading or short swims, though caution is always advised due to the river’s natural flow.
For more comfortable bathing, residents often visit nearby ponds or small recreational lakes where the water warms more quickly and facilities are available. Nevertheless, the Jizera in Semily provides a natural, scenic option for those who enjoy cooler river water and a refreshing escape on hot summer days.