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Avellanas Rivermouth Surf Forecast
/ Guanacaste (28 surf breaks) /
Surf Forecasts:
Avellanas Rivermouth surfForecast / Guanacaste / Costa Rica
16 Day Weather and Surf, issued 11 pm Tuesday 12 May 2026 CSTForecast update in hr min s Forecast update imminent
Avellanas Rivermouth surf forecast is for near shore open water. Breaking waves will often be smaller at less exposed spots.
Today's Avellanas Rivermouth sea temperature is
30.1° C
(Which is 1.2°C warmer than normal for this time of year)Best Forecast Surf Conditions for Avellanas Rivermouth this week:
The surf forecast for Avellanas Rivermouth over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Thursday (May 14) at 12PM. The primary swell is predicted to be 1.1m and 14s period with a secondary swell of 0.7m and 10s. The wind is predicted to be glassy as the swell arrives.
The most powerful waves expected at Avellanas Rivermouth in the next 16 days are 1.1m 15s and forecast to arrive on Thursday (May 14) at 3AM. Winds are predicted to be onshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 0.4m 5s period and expected on Wednesday (May 13) at 12PM.
| Wave Type | Time (CST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 12PM (Thu 14th May) | 3.5ft (1.1m) 14s |
| Best Surf | 12PM (Thu 14th May) | 3.5ft (1.1m) 14s |
| Most Powerful | 3AM (Thu 14th May) | 3.5ft (1.1m) 15s |
Table - best surf conditions forecast for Avellanas Rivermouth over the next 16 days.
Updates in hr min s Forecast update imminent
Short Range ForecastSome drizzle, heaviest during Thu afternoon. Warm (max 33°C on Thu morning, min 26°C on Tue night). Wind will be generally light. | Days 5-7 Weather SummaryLight rain (total 5mm), mostly falling on Sun afternoon. Warm (max 32°C on Mon morning, min 27°C on Fri night). Wind will be generally light. | ||||||||||||||||||||
Wednesday 13 | Thursday 14 | Friday 15 | Saturday 16 | Sunday 17 | Monday 18 | Tue 19 | |||||||||||||||
Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | |
Swell Height Map |  |  |  |  |  |  |  |  | |||||||||||||
SW 14 | SSW 17 | SW 16 | SW 15 | SW 15 | SW 14 | SW 14 | SW 14 | SW 14 | SW 14 | SW 13 | SW 13 | SW 13 | SW 14 | SSW 14 | SW 13 | SW 13 | SW 13 | SW 17 | SW 18 | SW 14 | |
203 | 184 | 216 | 516 | 551 | 529 | 357 | 469 | 469 | 373 | 347 | 253 | 253 | 288 | 253 | 178 | 175 | 178 | 243 | 154 | 208 | |
Wind (km/h) | |||||||||||||||||||||
on | cross-on | cross | on | cross-on | cross-off | on | cross-on | cross | on | cross-on | cross-off | cross-on | on | cross-off | on | cross-on | cross-off | on | on | cross-off | |
High Tide | 11:27AM2.22m | 11:58PM2.00m | 12:19PM2.38m | 00:52AM2.12m | 1:10PM2.54m | 1:44AM2.24m | 2:00PM2.66m | 2:35AM2.34m | 2:50PM2.73m | 3:25AM2.42m | 3:41PM2.74m | 4:16AM2.45m | 4:32PM2.70m | ||||||||
Low Tide | 5:03AM0.62m | 5:53PM0.52m | 5:57AM0.52m | 6:46PM0.35m | 6:50AM0.40m | 7:36PM0.18m | 7:42AM0.28m | 8:26PM0.04m | 8:33AM0.18m | 9:15PM-0.05m | 9:25AM0.13m | 10:04PM-0.08m | 10:17AM0.13m | ||||||||
 |  | | | |  | |  | | | | |  | | | | | | | |  | |
 | — | 5:22 | — | — | 5:22 | — | — | 5:22 | — | — | 5:20 | — | — | 5:20 | — | — | 5:20 | — | — | 5:20 | — |
 | — | — | 5:57 | — | — | 5:57 | — | — | 5:57 | — | — | 5:57 | — | — | 5:57 | — | — | 5:58 | — | — | 5:58 |
— | — | — | — | — | 1 | — | — | — | — | — | — | 1 | — | 3 | 1 | — | — | 1 | — | 8 | |
Temp °C | 29 | 32 | 31 | 29 | 33 | 30 | 29 | 33 | 31 | 30 | 31 | 29 | 28 | 31 | 30 | 29 | 32 | 30 | 29 | 30 | 29 |
32 | 33 | 34 | 30 | 36 | 33 | 28 | 34 | 33 | 31 | 33 | 31 | 32 | 33 | 32 | 32 | 34 | 32 | 33 | 32 | 31 | |
Swell 1 Height (m) Direction Period (s) | S 10 | S 10 | S 10 | SW 15 | SW 15 | SW 14 | SW 14 | SW 14 | SW 14 | SW 14 | SW 13 | SW 13 | SW 13 | SW 14 | SSW 14 | SW 13 | SW 13 | SW 13 | SSW 13 | SW 12 | SW 14 |
 kJ | 131 | 136 | 92 | 516 | 551 | 529 | 357 | 469 | 469 | 373 | 347 | 253 | 253 | 288 | 253 | 178 | 175 | 178 | 114 | 126 | 208 |
Swell 2 Height (m) Direction Period (s) | SW 14 | SW 14 | SW 14 | S 10 | S 10 | S 10 | SSW 16 | S 10 | S 10 | S 10 | S 9 | S 9 | S 9 | S 9 | S 8 | S 8 | S 8 | S 8 | SW 17 | S 7 | S 7 |
| kJ | 203 | 147 | 147 | 138 | 102 | 96 | 223 | 48 | 48 | 47 | 42 | 40 | 25 | 23 | 35 | 19 | 18 | 28 | 243 | 25 | 25 |
Swell 3 Height (m) Direction Period (s) | SW 18 | SSW 17 | SW 16 | W 12 | NW 15 | NNW 4 | S 10 | W 13 | NNW 4 | NW 12 | NNW 12 | NNW 4 | SW 20 | N 4 | NNW 4 | SW 18 | SW 17 | SW 16 | S 8 | SW 18 | SW 18 |
| kJ | 81 | 184 | 216 | 3 | 9 | 2 | 68 | 4 | 6 | 6 | 14 | 2 | 15 | 1 | 4 | 81 | 77 | 69 | 28 | 154 | 109 |
Wind waves Height (m) Direction Period (s) | NE 4 | — | — | NNE 4 | — | — | — | N 8 | — | NE 2 | — | — | NNE 4 | — | — | NNE 4 | NNE 2 | SW 2 | — | NNE 4 | — |
| kJ | 1 | — | — | 3 | — | — | — | 10 | — | 1 | — | — | 4 | — | — | 4 | 1 | 1 | — | 4 | — |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 1 | 8 | 8 | 1 | 1 | 0 | 1 | 19 | 64 | 1 | 1 | 65 | 1 | 1 | 0 | 1 | 1 | 65 | 1 | 1 | 68 |
Best forecast wave conditions in Guanacaste | |||||||||||||||||||||
Best forecast wave conditions in Costa Rica | |||||||||||||||||||||
Header Global | |||||||||||||||||||||
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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 Avellanas Rivermouth 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 Avellanas Rivermouth Surf forecast
The above surf forecast table for Avellanas Rivermouth provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Avellanas Rivermouth can be found by selecting the local surf guide option on the grey menu. Our Avellanas Rivermouth 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 (Avellanas Rivermouth) 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 Avellanas Rivermouth 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.
Avellanas Rivermouth is 44 km (27 miles) from Nicoya. If you plan a holiday in Guanacaste, look for hotels and other accommodation in Nicoya. Nicoya has rooms for a wide range of budgets as well as car hire and transport links.
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