Surf Forecasts:
Porth Nefyn surf forecast from 14 Sep 2026:
- Best quality surf: Sunday 20 Sep, 1AM (local time) - 4ft (1.2m), 6s period, SW swell with cross-offshore winds.
- Most powerful swell: Tuesday 15 Sep, 1AM (local time) - 5.5ft (1.7m), 6s period, SW swell with 210 kJ wave energy.
- Next surfable swell (1★+): Sunday 20 Sep, 1AM (local time) - 4ft (1.2m), 6s period with SW swell.
Best Forecast Surf Conditions for Porth Nefyn this week:
The surf forecast for Porth Nefyn over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Sunday (Sep 20) at 1AM. The primary swell is predicted to be 1.2m and 6s period with a secondary swell of 0.9m and 6s. The wind is predicted to be cross-offshore as the swell arrives.
The most powerful waves expected at Porth Nefyn in the next 16 days are 1.7m 6s and forecast to arrive on Tuesday (Sep 15) at 1AM. Winds are predicted to be cross-offshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 1.6m 6s period and expected on Monday (Sep 14) at 10PM.
| Wave Type | Time (BST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 1AM (Sun 20th Sep) | 4ft (1.2m) 6s |
| Best Surf | 1AM (Sun 20th Sep) | 4ft (1.2m) 6s |
| Most Powerful | 1AM (Tue 15th Sep) | 5.5ft (1.7m) 6s |
Table - best surf conditions forecast for Porth Nefyn over the next 16 days.
Short Range ForecastModerate rain (total 15mm), heaviest on Mon night. Very mild (max 18°C on Mon night, min 13°C on Tue night). Winds increasing (light winds from the S on Mon morning, fresh winds from the SW by Wed night). | Days 4-6 Weather SummaryLight rain (total 3mm), mostly falling on Fri afternoon. Very mild (max 18°C on Sat night, min 13°C on Thu night). Winds decreasing (fresh winds from the SSW on Fri afternoon, light winds from the SSW by Sat night). | ||||||||||||||||||||
Monday 14 | Tuesday 15 | Wednesday 16 | Thursday 17 | Friday 18 | Saturday 19 | Sunday 20 | |||||||||||||||
AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | |
Swell Height Map |  |  |  |  |  |  |  | ||||||||||||||
Wave Height (m) Direction Period (s) | W 12 | SW 5 | SW 6 | WSW 5 | WSW 5 | NW 5 | NW 5 | WNW 4 | SW 4 | WSW 6 | W 5 | W 5 | WSW 5 | NW 4 | SW 6 | SW 6 | SW 6 | SW 6 | W 14 | W 14 | SW 5 |
Wave Graph  | |||||||||||||||||||||
 kJ | 3 | 0 | 210 | 82 | 69 | 55 | 85 | 18 | 0 | 131 | 59 | 62 | 37 | 3 | 167 | 161 | 132 | 109 | 4 | 4 | 14 |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-off | cross-off | cross-off | cross-on | cross-on | on | cross-on | cross | cross-off | cross-on | cross-on | cross-on | cross | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | off |
High Tide | 11:08AM3.73m | 11:26PM3.86m | 11:43AM3.58m | 00:03AM3.56m | 12:18PM3.35m | 00:40AM3.22m | 12:55PM3.08m | 1:21AM2.87m | 1:39PM2.79m | 2:15AM2.54m | 2:47PM2.53m | 3:59AM2.32m | 4:58PM2.46m | ||||||||
Low Tide | 6:03PM0.23m | 6:26AM0.35m | 6:37PM0.46m | 6:57AM0.68m | 7:12PM0.74m | 7:30AM1.00m | 7:51PM1.03m | 8:09AM1.29m | 8:42PM1.30m | 9:08AM1.51m | 10:04PM1.49m | 10:42AM1.61m | 11:54PM1.46m | ||||||||
 |  |  | |  | |  | | | | |  | | |  | | | | |  |  | |
 | 6:48 | — | — | 6:50 | — | — | 6:52 | — | — | 6:54 | — | — | 6:56 | — | — | 6:56 | — | — | 6:58 | — | — |
 | — | 7:37 | — | — | 7:35 | — | — | 7:31 | — | — | 7:30 | — | — | 7:27 | — | — | 7:24 | — | — | 7:22 | — |
mm | — | — | 8 | — | 3 | 1 | 1 | — | 2 | — | — | — | — | 1 | 2 | — | — | — | — | — | — |
Temp °C | 17 | 17 | 18 | 15 | 16 | 15 | 13 | 15 | 15 | 15 | 15 | 14 | 14 | 15 | 16 | 17 | 17 | 18 | 18 | 18 | 17 |
Feels °C | 16 | 13 | 14 | 9 | 11 | 10 | 7 | 11 | 9 | 9 | 10 | 7 | 10 | 9 | 11 | 14 | 14 | 17 | 16 | 16 | 15 |
Swell 1 Height (m) Direction Period (s) | W 12 | — | — | — | — | SW 6 | SW 6 | SW 5 | — | — | — | W 11 | — | NW 4 | — | — | — | SW 6 | W 14 | W 14 | SW 5 |
| kJ | 3 | — | — | — | — | 29 | 9 | 4 | — | — | — | 3 | — | 3 | — | — | — | 62 | 4 | 4 | 14 |
Swell 2 Height (m) Direction Period (s) | — | — | — | — | — | W 11 | W 11 | W 11 | — | — | — | — | — | — | — | — | — | — | — | — | W 14 |
| kJ | — | — | — | — | — | 2 | 2 | 2 | — | — | — | — | — | — | — | — | — | — | — | — | 4 |
Swell 3 Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| kJ | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
Wind waves Height (m) Direction Period (s) | SW 5 | SW 5 | SW 6 | WSW 5 | WSW 5 | NW 5 | NW 5 | WNW 4 | SW 4 | WSW 6 | W 5 | W 5 | WSW 5 | SW 5 | SW 6 | SW 6 | SW 6 | SW 6 | SW 5 | SW 5 | SSW 4 |
| kJ | 24 | 51 | 210 | 82 | 69 | 55 | 85 | 18 | 40 | 131 | 59 | 62 | 37 | 53 | 167 | 161 | 132 | 109 | 27 | 18 | 13 |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 268 | 268 | 267 | 496 | 510 | 142 | 157 | 287 | 297 | 306 | 510 | 142 | 154 | 373 | 268 | 268 | 268 | 62 | 268 | 268 | 141 |
Best forecast wave conditions in Lleyn Peninsula | |||||||||||||||||||||
Best forecast wave conditions in United Kingdom | |||||||||||||||||||||
Header Global | |||||||||||||||||||||
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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 Porth Nefyn 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.
Information about the Porth Nefyn Surf forecast
The above surf forecast table for Porth Nefyn provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Porth Nefyn can be found by selecting the local surf guide option on the grey menu. Our Porth Nefyn 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 (Porth Nefyn) 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 Porth Nefyn 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.
Are you planning a holiday in Lleyn Peninsula? If you are looking for accommodation near Porth Nefyn, camping, hotels and holiday cottages in Lleyn Peninsula, consider staying in Porthmadog which is 27 km (17 miles) away. Other places in and around Lleyn Peninsula where you can find information about places to rent, and car hire include Anglesey which is 35 km (22 miles) away, Holyhead, Bangor and Llandudno.
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