Iskar River — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in the Iskar River, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in the Iskar River today is 18.6°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
⚠️ As of today, the minimum water temperature ranges from 65°F (18°C) to 68°F (20°C). This is already quite warm water, which is ideal for most people. Swimming becomes comfortable, and prolonged stays in the water do not cause discomfort. This temperature is perfect for family trips and for those who prefer warmer water. It is also comfortable for water sports such as surfing or swimming. 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 |
|---|---|---|---|
| JUN 3 | 17.2°C | 16.0°C | |
| JUN 4 | 17.1°C | 16.0°C | |
| JUN 5 | 17.1°C | 16.0°C | |
| JUN 6 | 17.5°C | 16.0°C | |
| JUN 7 | 17.5°C | 16.0°C | |
| JUN 8 | 17.5°C | 16.0°C | |
| JUN 10 | 18.6°C | 16.0°C | |
| JUN 11 | 16.0°C | 18.5°C | |
| JUN 12 | 16.0°C | 18.3°C | |
| JUN 13 | 16.0°C | 18.2°C | |
| JUN 14 | 16.0°C | 18.1°C | |
| JUN 15 | 16.0°C | 18.0°C | |
| JUN 16 | 16.0°C | 17.8°C | |
| JUN 17 | 16.0°C | 17.7°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 | 2°C | 6°C | 9°C |
| February | 2°C | 6°C | 9°C |
| March | 3°C | 7°C | 11°C |
| April | 5°C | 9°C | 13°C |
| May | 7°C | 13°C | 18°C |
| June | 11°C | 16°C | 20°C |
| July | 14°C | 18°C | 23°C |
| August | 14°C | 18°C | 23°C |
| September | 11°C | 16°C | 20°C |
| October | 9°C | 13°C | 16°C |
| November | 5°C | 9°C | 12°C |
| December | 2°C | 6°C | 9°C |
Iskar River: Water Temperature by Location
Iskar River: Weather Forecast
June 9
June 10
June 11
June 12
June 13
Location & Local Information
Source Damga Peak
• location Rila Mountains, Sofia Province
• coordinates 42°11′40″N 23°19′50″E
• elevation 2,500 m (8,200 ft)
Mouth Danube River
• location north of Gigen, Pleven Province
• coordinates 43°43′56″N 24°26′29″E
• elevation 25 m (82 ft)
Length 368.0 km (228.7 mi)
The Iskar (Искър) is Bulgaria’s longest river and its water temperature varies widely with location and season. In winter the surface water in many stretches can fall to about 0–4 °C (32–39 °F), while spring temperatures typically rise from roughly 5–12 °C (41–54 °F) as snowmelt and rainfall feed the river. In summer the lower valley and reservoir sections warm most, often reaching about 18–25 °C (64–77 °F) on sunny days, whereas mountain reaches and fast-flowing riffles usually remain cooler, around 12–18 °C (54–64 °F). In autumn the river cools again to roughly 6–14 °C (43–57 °F) before winter lows return.
Swimming in the Iskar is commonly done in warm months in calmer reaches and in some reservoirs, but it is not uniformly permitted or safe everywhere. Restrictions can apply near reservoirs used for drinking water, and local authorities may ban bathing in protected or polluted stretches. Even where swimming is allowed, hazards such as strong currents, sudden depth changes, submerged obstacles, boat traffic and variable water quality make caution essential. Visitors should observe local signage, follow municipal rules and assess conditions before entering the water, choosing sheltered, monitored spots when available.