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Harlech surfForecast / Wales – Mid / UK
12 Day Weather and Surf, issued 5 pm Wednesday 17 Dec 2025 GMTForecast update in hr min s Forecast update imminent
Harlech surf forecast is for near shore open water. Breaking waves will often be smaller at less exposed spots.
Today's Harlech sea temperature is
9.4° C
(Which is slightly cooler than normal)Best Forecast Surf Conditions for Harlech this week:
The surf forecast for Harlech over the next 12 days: The first swell (rated 1 star or higher) is forecast to arrive on Thursday (Dec 18) at 12PM. The primary swell is predicted to be 0.5m and 20s period with a secondary swell of 0.8m and 5s. Another secondary swell of 0.6m and 9s is also forecast. The wind is predicted to be cross-offshore as the swell arrives.
The most powerful waves expected at Harlech in the next 12 days are 2.2m 9s and forecast to arrive on Friday (Dec 19) at 6AM. Winds are predicted to be cross-onshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 1.1m 4s period and expected on Saturday (Dec 20) at 9PM.
| Wave Type | Time (GMT) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 12PM (Thu 18th Dec) | 1.5ft (0.5m) 20s |
| Best Surf | 12PM (Thu 18th Dec) | 1.5ft (0.5m) 20s |
| Most Powerful | 6AM (Fri 19th Dec) | 7ft (2.2m) 9s |
Table - best surf conditions forecast for Harlech over the next 12 days.
Updates in hr min s Forecast update imminent
Short Range Forecast Heavy rain (total 39mm), heaviest during Wed night. Very mild (max 11°C on Wed afternoon, min 8°C on Thu afternoon). Winds increasing (light winds from the SSE on Thu morning, strong winds from the SW by Thu night). | Days 3-6 Weather Summary Light rain (total 4mm), mostly falling on Sat night. Mild temperatures (max 9°C on Sat afternoon, min 7°C on Sat night). Winds decreasing (fresh winds from the SSE on Sat afternoon, calm by Mon afternoon). | ||||||||||||||||||||||
Wed 17 | Thursday 18 | Friday 19 | Saturday 20 | Sunday 21 | Monday 22 | Tuesday 23 | |||||||||||||||||
| PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | |||
Rating (10 max) | |||||||||||||||||||||||
Swell Height Map |  |  |  |  |  |  |  |  | |||||||||||||||
| Wave Height (m) & direction (?) | |||||||||||||||||||||||
| Period(s) (?) | 9 | 9 | 20 | 9 | 6 | 9 | 7 | 6 | 8 | 10 | 11 | 17 | 16 | 10 | 9 | 7 | 8 | 8 | 9 | 9 | 9 | ||
Wave (?)Graph  | |||||||||||||||||||||||
 kJ (?) | 623 | 563 | 225 | 210 | 271 | 730 | 293 | 167 | 262 | 588 | 258 | 168 | 87 | 36 | 33 | 25 | 18 | 11 | 7 | 3 | 1 | ||
Wind (km/h) | |||||||||||||||||||||||
| Wind State (?) onshore cross-onshore cross-shore cross-offshore offshore glassy | cross | cross- on | cross- off | cross- on | cross- on | cross- on | cross- on | cross | cross- off | cross- off | cross- off | off | off | off | glass | glass | cross- off | cross- off | cross- off | cross- off | cross- off | ||
High Tide / height (m) | 6:30PM 3.57 | 6:50AM 3.71 | 7:08PM 3.69 | 7:26AM 3.87 | 7:44PM 3.78 | 8:01AM 3.99 | 8:19PM 3.83 | 8:36AM 4.08 | 8:53PM 3.84 | 9:11AM 4.13 | 9:28PM 3.80 | 9:47AM 4.13 | 10:05PM 3.74 | 10:24AM 4.10 | |||||||||
Low Tide / height (m) | 1:27AM 0.98 | 1:51PM 0.91 | 2:04AM 0.89 | 2:29PM 0.80 | 2:41AM 0.82 | 3:07PM 0.72 | 3:17AM 0.77 | 3:46PM 0.68 | 3:54AM 0.76 | 4:25PM 0.69 | 4:30AM 0.79 | 5:05PM 0.73 | 5:07AM 0.86 | ||||||||||
Wed 17 | Thursday 18 | Friday 19 | Saturday 20 | Sunday 21 | Monday 22 | Tuesday 23 | |||||||||||||||||
| Sunrise | - | - | 8:23 | - | - | 8:25 | - | - | 8:25 | - | - | 8:26 | - | - | 8:26 | - | - | 8:26 | - | - | 8:26 | ||
| Sunset | 4:00 | - | - | 4:00 | - | - | 4:00 | - | - | 4:00 | - | - | 4:01 | - | - | 4:01 | - | - | 4:02 | - | - | ||
 |  |  |  |  |  | |  |  |  |  | | |  |  | | | | | | | |||
Rain (mm) | 11 | 15 | 2 | 6 | 2 | 2 | 1 | - | - | - | 2 | - | 2 | - | - | - | - | - | - | - | - | ||
| Temp. °C | 11 | 11 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 8 | 8 | 9 | 9 | 9 | 9 | 8 | 8 | 8 | 7 | 6 | ||
| Feels °C (?) | 4 | 5 | 4 | 4 | 0 | 2 | 2 | 2 | 2 | 1 | 2 | 3 | 5 | 5 | 7 | 7 | 5 | 4 | 3 | 2 | 2 | ||
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The surf report / weather widget below is available to embed on third party websites free of charge and provides a summary of our Harlech surf forecast. Simply grab the html code snippet that we provide and paste it into your own site. You can choose your preferred language and metric/imperial units for the surf forecast feed to suit users of your site. Click here to get the code.
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Information about the Harlech Surf forecast
The above surf forecast table for Harlech provides essential information for determining whether the surfing conditions will be good over the next 12 days. A general guide to surfing at Harlech can be found by selecting the local surf guide option on the grey menu. Our Harlech surf forecast is unique since it includes wave energy (power) that defines the real feel of the surf rather than just the height or the period. If you surf the same spot (Harlech) regularly then make a mental note of the wave energy from the surf forecast table each time you go. Very soon you may start to choose your surf days based on the wave energy alone combined with our forecast of favourable offshore wind conditions. Our star ratings will help here and of course you will also find the usual wave height and period predictions on our surf forecasts as well as a full break down of the swell components under our advanced users option (to reveal that, click the little Einstein character under the tide times).
Further information to help with frequently asked questions about our surf forecast for Harlech may be found under the help tab on the top menu and also by moving your mouse over the question marks on the surf forecast table itself. Please always bear in mind that the forecast is for near-shore open water and local factors at each surf break influence the actual breaking wave height, such as the beach / reef profile, water depths offshore and shelter.
Harlech is 9 km (6 miles) from Porthmadog. If you plan a holiday in Mid Wales, look for hotels and other accommodation in Porthmadog. Porthmadog has rooms for a wide range of budgets as well as car hire and transport links.
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