Surf Forecasts:
Guethary - Les Alcyons/Avalanche surf forecast from 31 Jul 2026:
- Most powerful swell: Saturday 1 Aug, 11AM (local time) - 2.5ft (0.7m), 8s period, NW swell with 65 kJ wave energy.
Best Forecast Surf Conditions for Guethary - Les Alcyons/Avalanche this week:
The most powerful waves expected at Guethary - Les Alcyons/Avalanche in the next 16 days are 0.7m 8s and forecast to arrive on Saturday (Aug 01) at 11AM. Winds are predicted to be cross-onshore at the time the swell arrives.
| Wave Type | Time (CEST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | - | - |
| Best Surf | - | - |
| Most Powerful | 11AM (Sat 1st Aug) | 2.5ft (0.7m) 8s |
Table - best surf conditions forecast for Guethary - Les Alcyons/Avalanche over the next 16 days.
The Lowdown
Alright, this is a tough one to call, but I’ll shoot it straight.
Look, for the next couple of weeks, we’re looking at a pretty grim picture at Guethary - Les Alcyons/Avalanche. This is a reef break that’s known for being an expert-only wave, and the conditions we’ve got lined up just aren’t going to cooperate. The swell is tiny, the wind is messy, and it’s going to be a long wait.
The first day worth even mentioning kicks off on Friday, 31 July, but don’t get your hopes up. We’re looking at a weak 2ft swell from the NW with a short, wobbly 8-second period. The combined energy is a measly 66 (weak), and the wind is a cross-on from the NNW at 3 mph. It’s a poor surf setup. The water is a very unusual 77°F (that’s 6°F warmer than normal for this time of year), which is nice for a swim but not for the waves.
Saturday and Sunday (1st and 2nd of August) are more of the same. Tiny, weak swell in the 2ft to 3ft range. Sunday morning does go glassy, which is a beautiful thing, but with a 6-second period swell at 2ft, it’s barely a ripple. The combined energy is still weak (54 on Sunday morning). There’s just no push.
From Monday the 3rd of August right through to the 15th of August, the forecast is a dead loss. The swell height barely breaks 2ft, the period is mostly short and weak, and the wind is consistently onshore or cross-on. The combined energy values are all in the weak two-digit range, often dropping below 40. There’s simply no wave size to work with. Even when we get a glassy morning on the 9th and 10th of August, the swell is just too small (1ft to 2ft) to break properly over the reef.
The best of a bad bunch? Honestly, there isn’t a standout. The best possible window is Sunday morning, 9 August, and Monday morning, 10 August, with glassy conditions and a 1ft to 2ft swell from the WNW. The period is 8 to 9 seconds, so it’s not total junk, but the size is just too small for this break to offer anything meaningful. It’s a longboard or a flat day, plain and simple.
Don’t bank on any of this. It’s a solid 16-day stretch of poor surf. For a consistent reef break like this, it’s unusual to see such a blank run, but that’s the hand we’ve been dealt.
Rusty.
Short Range ForecastMostly dry. Warm (max 23°C on Sun afternoon, min 18°C on Sat night). Wind will be generally light. | Days 4-6 Weather SummarySome drizzle, heaviest during Wed night. Warm (max 23°C on Mon afternoon, min 18°C on Mon night). Wind will be generally light. | ||||||||||||||||||||
Friday 31 | Saturday 1 | Sunday 2 | Monday 3 | Tuesday 4 | Wednesday 5 | Thursday 6 | |||||||||||||||
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) | NW 8 | NW 8 | NW 8 | NW 8 | NW 7 | NNW 6 | NNW 6 | NNW 6 | NW 6 | WNW 10 | WNW 10 | WNW 10 | WNW 9 | WNW 9 | WNW 9 | WNW 8 | WNW 8 | WNW 8 | WNW 8 | WNW 8 | WNW 7 |
Wave Graph  | |||||||||||||||||||||
 kJ | 66 | 53 | 36 | 65 | 65 | 25 | 30 | 25 | 33 | 19 | 18 | 18 | 27 | 26 | 25 | 23 | 13 | 12 | 23 | 22 | 20 |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-on | on | glassy | cross-on | on | cross | glassy | on | cross-on | cross-on | on | glassy | on | cross-on | cross | cross-on | on | on | on | on | on |
High Tide | 6:42PM3.71m | 7:01AM3.45m | 7:14PM3.71m | 7:33AM3.44m | 7:47PM3.66m | 8:08AM3.39m | 8:23PM3.55m | 8:46AM3.30m | 9:03PM3.40m | 9:30AM3.18m | 9:53PM3.21m | 10:24AM3.04m | 10:56PM3.03m | ||||||||
Low Tide | 12:26PM0.39m | 00:52AM0.31m | 12:59PM0.37m | 1:25AM0.31m | 1:33PM0.40m | 1:59AM0.36m | 2:09PM0.48m | 2:36AM0.46m | 2:49PM0.60m | 3:18AM0.62m | 3:37PM0.76m | 4:09AM0.80m | 4:37PM0.91m | ||||||||
 |  |  |  | |  | | | | | | | | | | | |  | | | | |
 | 6:54 | — | — | 6:54 | — | — | 6:56 | — | — | 6:56 | — | — | 6:58 | — | — | 6:58 | — | — | 7:00 | — | — |
 | — | — | 9:30 | — | — | 9:29 | — | — | 9:28 | — | — | 9:27 | — | — | 9:24 | — | — | 9:23 | — | — | 9:22 |
mm | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 1 | — | — | — |
Temp °C | 21 | 22 | 21 | 20 | 22 | 21 | 22 | 23 | 22 | 21 | 23 | 22 | 21 | 23 | 22 | 21 | 23 | 21 | 21 | 22 | 21 |
Feels °C | 23 | 23 | 22 | 21 | 21 | 21 | 23 | 23 | 21 | 22 | 24 | 23 | 22 | 23 | 22 | 22 | 24 | 22 | 23 | 22 | 21 |
Swell 1 Height (m) Direction Period (s) | NW 8 | NW 8 | NW 8 | NW 8 | NW 7 | NNW 6 | NNW 6 | NNW 6 | NW 6 | NW 4 | NW 4 | NW 4 | WNW 9 | WNW 9 | WNW 9 | WNW 8 | WNW 8 | WNW 8 | WNW 8 | WNW 8 | WNW 7 |
| kJ | 66 | 53 | 36 | 65 | 65 | 25 | 30 | 25 | 33 | 12 | 6 | 5 | 27 | 26 | 25 | 23 | 13 | 12 | 23 | 22 | 20 |
Swell 2 Height (m) Direction Period (s) | — | — | NW 9 | W 9 | WNW 10 | NW 7 | WNW 9 | NW 7 | WNW 11 | WNW 10 | WNW 10 | WNW 10 | NW 5 | NNW 5 | NNW 4 | NNW 4 | W 11 | NNW 4 | N 4 | WNW 10 | N 4 |
| kJ | — | — | 3 | 6 | 10 | 14 | 16 | 7 | 11 | 19 | 18 | 18 | 6 | 2 | 2 | 3 | 2 | 2 | 2 | 10 | 5 |
Swell 3 Height (m) Direction Period (s) | — | — | W 12 | W 11 | W 9 | WNW 9 | NW 7 | WNW 9 | — | NW 7 | NW 7 | — | NNW 7 | NW 7 | NW 7 | — | — | WNW 10 | WNW 10 | — | WNW 10 |
| kJ | — | — | 3 | 2 | 6 | 16 | 8 | 8 | — | 7 | 7 | — | 5 | 2 | 2 | — | — | 10 | 10 | — | 10 |
Wind waves Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | NNW 4 | — | — | NNW 4 | — |
| kJ | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 3 | — | — | 2 | — |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 530 | 1576 | 1 | 17 | 87 | 14 | 1 | 795 | 47 | 345 | 485 | 21 | 278 | 534 | 125 | 333 | 789 | 333 | 331 | 495 | 344 |
Best forecast wave conditions in La Cote Basque | |||||||||||||||||||||
Best forecast wave conditions in France | |||||||||||||||||||||
Header Global | |||||||||||||||||||||
- Map Icons:
Break
Live Wave Height (m)
Live Wind Speed (km/h)
Surf Rating (10 Max)
Ocean Swells (m)- Wind Speed (km/h)
Latest Updates
FREE! Surf-Forecast.com widget for your website
The surf report / weather widget below is available to embed on third party websites free of charge and provides a summary of our Guethary - Les Alcyons/Avalanche 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 Guethary - Les Alcyons/Avalanche Surf forecast
The above surf forecast table for Guethary - Les Alcyons/Avalanche provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Guethary - Les Alcyons/Avalanche can be found by selecting the local surf guide option on the grey menu. Our Guethary - Les Alcyons/Avalanche 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 (Guethary - Les Alcyons/Avalanche) 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 Guethary - Les Alcyons/Avalanche 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.
Guethary - Les Alcyons/Avalanche is 9 km (6 miles) from Biarritz. If you plan a holiday in La Cote Basque, look for hotels and other accommodation in Biarritz. Biarritz has rooms for a wide range of budgets as well as car hire and transport links.
Nearest