Using Surf-Forecast’s Historical Surf Data To Find The Most Consistent Waves On Earth
Using our statistical data for 7000 spots dating back to 2006, we can find those waves that break the most, with the best winds.
Surf Forecasts:
Portstewart Strand surfForecast / Londonderry / Ireland
48hr Weather and Surf, issued 11 am Thursday 18 Dec 2025 GMTForecast update in hr min s Forecast update imminent
Portstewart Strand surf forecast is for near shore open water. Breaking waves will often be smaller at less exposed spots.
Today's Portstewart Strand sea temperature is
10.7° C
(Which is slightly warmer than usual)How big are the waves at Portstewart Strand today?
The current surf forecast for Portstewart Strand at 2PM is: 3.0m 19s primary swell from a Northwest direction (forecast issued at 11:00am December 18). An open ocean swell of 0.7m 4s is not directed at the surf break. The wind direction is predicted to be cross-offshore and the swell rating is 11.
| Time (GMT) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (18 Dec) | 10ft (3.0m) | 20s |
| Afternoon (18 Dec) | 10ft (3.0m) | 19s |
| Evening (18 Dec) | 10ft (3.0m) | 18s |
Table - waves today at Portstewart Strand. (Swell directed towards the surf break)
Updates in hr min s Forecast update imminent
Thursday 18 | Friday 19 | Saturday 20 | Sunday 21 | |||||||||||||||||||||
| 9 AM | 12 PM | 3 PM | 6 PM | 9 PM | 0 AM | 3 AM | 6 AM | 9 AM | 12 PM | 3 PM | 6 PM | 9 PM | 0 AM | 3 AM | 6 AM | 9 AM | 12 PM | 3 PM | 6 PM | 9 PM | 0 AM | 3 AM | 6 AM | |
Rating (10 max) | ||||||||||||||||||||||||
Swell Height Map |    |    |    |    | ||||||||||||||||||||
| Wave Height (m) & direction (?) | ||||||||||||||||||||||||
| Period(s) (?) | 20 | 19 | 19 | 19 | 18 | 18 | 17 | 17 | 16 | 16 | 16 | 15 | 14 | 14 | 13 | 13 | 13 | 12 | 12 | 13 | 12 | 16 | 16 | 16 |
Wave (?)Graph  | ||||||||||||||||||||||||
 kJ (?) | 8056 | 7202 | 6645 | 6576 | 5152 | 4434 | 3850 | 3166 | 2831 | 3456 | 3412 | 2795 | 2144 | 1558 | 933 | 613 | 364 | 264 | 268 | 249 | 309 | 976 | 1922 | 2589 |
Wind (km/h) | ||||||||||||||||||||||||
| Wind State (?) onshore cross-onshore cross-shore cross-offshore offshore glassy | cross- off | cross- off | cross- off | cross | cross- off | cross- off | cross | cross | cross | cross | cross | cross- off | cross- off | cross- off | cross- off | cross- off | off | cross- off | cross- off | cross- off | off | cross- on | cross- off | off |
High Tide / height (m) | 5:06PM 1.48 | 5:29AM 1.61 | 5:39PM 1.50 | 6:02AM 1.66 | 6:11PM 1.52 | |||||||||||||||||||
Low Tide / height (m) | 11:20AM 0.38 | 11:27PM 0.31 | 11:58AM 0.35 | 12:01AM 0.27 | 12:34PM 0.33 | 12:34AM 0.23 | ||||||||||||||||||
Thursday 18 | Friday 19 | Saturday 20 | Sunday 21 | |||||||||||||||||||||
| Sunrise | 8:48 | - | - | - | - | - | - | - | 8:48 | - | - | - | - | - | - | - | 8:49 | - | - | - | - | - | - | - |
| Sunset | - | - | 3:56 | - | - | - | - | - | - | - | 3:57 | - | - | - | - | - | - | - | 3:57 | - | - | - | - | - |
 | |  |  |  |  |  | |  |  | | | | | | | | | | | |  |  | | |
Rain (mm) | - | - | 3 | 3 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 6 | 2 | - |
| Temp. °C | 7 | 10 | 9 | 7 | 7 | 7 | 8 | 9 | 8 | 8 | 8 | 7 | 6 | 6 | 8 | 8 | 9 | 9 | 8 | 7 | 7 | 5 | 4 | 5 |
| Feels °C (?) | 1 | 1 | 3 | 2 | 0 | -2 | -1 | 0 | -1 | -1 | 0 | 0 | 0 | 0 | 0 | -1 | 0 | -1 | 2 | 4 | 4 | 1 | 0 | 2 |
- Map Icons:
Break
Live Wave Height (m)
Live Wind Speed (km/h)
Surf Rating (10 Max)
Ocean Swells (m)- Wind Speed (km/h)
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