Amsterdam Het IJ Water Temperature Today
Amsterdam Het IJ, a tidal river pool in North Holland, Netherlands. The water peaks in the high teens to low twenties in July and August, and is cold but ice-free in winter.
In August Amsterdam Het IJ averages about 21°C, peaking near 21°C in July, August, September and dropping to roughly 5°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.
Amsterdam Het IJ water temperature by month
| Month | Average water temperature | Swimming |
|---|---|---|
| January | 6.1°C | cold |
| February | 5.0°C | cold |
| March | 6.1°C | cold |
| April | 9.0°C | cold |
| May | 13.0°C | cool |
| June | 17.0°C | mild |
| July | 19.9°C | mild |
| August | 21.0°C | warm |
| September | 19.9°C | mild |
| October | 17.0°C | mild |
| November | 13.0°C | cool |
| December | 9.0°C | cold |
Amsterdam Het IJ swim conditions FAQ
What is the water temperature in Amsterdam Het IJ right now?
In August the water in Amsterdam Het IJ averages about 21°C. We refine that long-term average with today's air temperature, because this tidal pool responds quickly to the weather.
When is the best time to swim in Amsterdam Het IJ?
The comfortable swim season — 18°C or warmer — runs through July, August, September, with the warmest water in July, August, September at around 21°C.
Can you swim in Amsterdam Het IJ in winter?
Yes, but winter temperatures drop to roughly 5°C. Below 12°C, cold-water shock is the main risk: enter slowly, never swim alone, and limit time in the water.
Is Amsterdam Het IJ 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.
- Tidal water reverses direction — check the tide table before you swim.
Swim season here: July, August, September.