Mrežnica River Water Temperature Today
Mrežnica River, a river swimming spot in Karlovac, Croatia. The water reaches comfortable swimming temperatures in high summer, and is cold but ice-free in winter.
In August Mrežnica River averages about 23°C, peaking near 23°C in July, August, September and dropping to roughly 6°C at its coldest.
River and swimming-hole temperatures are modelled from long-term monthly averages and refined with live air temperature, wind and UV. Moving water reacts faster to the weather than a lake or the sea.
Mrežnica River water temperature by month
| Month | Average water temperature | Swimming |
|---|---|---|
| January | 7.1°C | cold |
| February | 6.0°C | cold |
| March | 7.1°C | cold |
| April | 10.3°C | cool |
| May | 14.5°C | cool |
| June | 18.8°C | mild |
| July | 21.9°C | warm |
| August | 23.0°C | warm |
| September | 21.9°C | warm |
| October | 18.8°C | mild |
| November | 14.5°C | cool |
| December | 10.3°C | cool |
Mrežnica River swim conditions FAQ
What is the water temperature in Mrežnica River right now?
In August the water in Mrežnica River averages about 23°C. We refine that long-term average with today's air temperature, because this river responds quickly to the weather.
When is the best time to swim in Mrežnica River?
The comfortable swim season — 18°C or warmer — runs through June, July, August, September, October, with the warmest water in July, August, September at around 23°C.
Can you swim in Mrežnica River in winter?
Yes, but winter temperatures drop to roughly 6°C. Below 12°C, cold-water shock is the main risk: enter slowly, never swim alone, and limit time in the water.
Is Mrežnica River safe for swimming?
Moving and inland water carries different risks from the sea: check flow after rain, avoid weirs and undercut banks, look for submerged rocks before jumping, and respect local access rules and water-quality notices.
Water safety tips
- Check the flow rate after heavy rain — inland water can rise and speed up within hours.
- Never jump before checking depth and submerged rocks; levels change through the season.
- Enter slowly to control cold-water shock, and get out before you start shivering.
- Swim with someone else and agree an exit point downstream before you start.
Swim season here: June, July, August, September, October.