Surf Forecasts:
Umatac surf forecast from 18 Oct 2026:
- Best quality surf: Friday 23 Oct, 10PM (local time) - 6ft (1.8m), 14s period, WNW swell with cross-offshore winds.
- Most powerful swell: Saturday 24 Oct, 1PM (local time) - 7ft (2.1m), 15s period, WNW swell with 1,924 kJ wave energy.
- Next surfable swell (1★+): Tuesday 20 Oct, 7AM (local time) - 3.5ft (1.0m), 10s period with WSW swell.
Best Forecast Surf Conditions for Umatac this week:
The surf forecast for Umatac over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Tuesday (Oct 20) at 7AM. The primary swell is predicted to be 1.0m and 10s period with a secondary swell of 0.9m and 11s. The wind is predicted to be offshore as the swell arrives.
The most powerful waves expected at Umatac in the next 16 days are 2.1m 15s and forecast to arrive on Saturday (Oct 24) at 1PM. Winds are predicted to be offshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 6.5m 11s period and expected on Sunday (Oct 18) at 4PM.
| Wave Type | Time (ChST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 7AM (Tue 20th Oct) | 3.5ft (1.0m) 10s |
| Best Surf | 10PM (Fri 23rd Oct) | 6ft (1.8m) 14s |
| Most Powerful | 1PM (Sat 24th Oct) | 7ft (2.1m) 15s |
Table - best surf conditions forecast for Umatac over the next 16 days.
Short Range ForecastHeavy rain (total 127mm), heaviest during Sun morning. Warm (max 28°C on Mon night, min 25°C on Sun morning). Winds decreasing (stormy winds from the SE on Sun morning, light winds from the E by Tue night). | Days 4-6 Weather SummaryMostly dry. Warm (max 28°C on Wed morning, min 26°C on Wed night). Wind will be generally light. | ||||||||||||||||||||
Sunday 18 | Monday 19 | Tuesday 20 | Wednesday 21 | Thursday 22 | Friday 23 | Saturday 24 | |||||||||||||||
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) | SE 11 | N 8 | NNE 11 | WSW 10 | WSW 10 | WSW 10 | WSW 10 | WNW 11 | SW 9 | W 12 | W 12 | W 12 | W 12 | W 13 | W 13 | WNW 13 | WNW 14 | WNW 14 | WNW 15 | WNW 15 | WNW 14 |
Wave Graph  | |||||||||||||||||||||
 kJ | 0 | 5 | 11 | 648 | 339 | 339 | 202 | 123 | 388 | 390 | 902 | 802 | 746 | 713 | 775 | 958 | 1106 | 1322 | 1898 | 1924 | 1158 |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | off | off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off |
High Tide | 2:36PM0.63m | 11:25PM0.56m | 3:32PM0.65m | 00:55AM0.54m | 4:14PM0.66m | 2:32AM0.54m | 4:46PM0.68m | 3:53AM0.57m | 5:13PM0.69m | 5:00AM0.61m | 5:38PM0.70m | 6:00AM0.66m | 6:01PM0.72m | ||||||||
Low Tide | 7:49PM0.52m | 7:29AM0.09m | 9:11PM0.48m | 8:33AM0.10m | 10:06PM0.43m | 9:31AM0.11m | 10:46PM0.36m | 10:24AM0.13m | 11:21PM0.27m | 11:12AM0.16m | 11:54PM0.18m | 11:56AM0.20m | 00:29AM0.07m | ||||||||
 | |  |  | |  |  | |  | |  |  | | | | | | | |  | | |
 | 6:11 | — | — | 6:11 | — | — | 6:11 | — | — | 6:11 | — | — | 6:11 | — | — | 6:11 | — | — | 6:13 | — | — |
 | — | 6:00 | — | — | 6:00 | — | — | 6:00 | — | — | 5:59 | — | — | 5:59 | — | — | 5:58 | — | — | 5:58 | — |
mm | 59 | 22 | 17 | 8 | 10 | 8 | — | 2 | 1 | — | — | — | — | — | — | — | — | — | — | 1 | 1 |
Temp °C | 26 | 26 | 27 | 26 | 26 | 28 | 28 | 28 | 27 | 28 | 28 | 27 | 28 | 28 | 27 | 28 | 28 | 27 | 28 | 28 | 27 |
Feels °C | 13 | 17 | 23 | 23 | 24 | 29 | 29 | 30 | 29 | 30 | 30 | 30 | 30 | 30 | 29 | 30 | 30 | 30 | 32 | 31 | 30 |
Swell 1 Height (m) Direction Period (s) | ENE 9 | NE 10 | ENE 10 | WSW 10 | WSW 10 | WSW 10 | WSW 10 | SW 9 | SW 9 | WSW 9 | W 12 | W 12 | W 12 | W 13 | W 13 | WNW 13 | WNW 14 | WNW 14 | WNW 15 | WNW 15 | WNW 14 |
| kJ | 320 | 108 | 80 | 648 | 339 | 339 | 201 | 586 | 388 | 264 | 902 | 802 | 746 | 713 | 775 | 958 | 1106 | 1322 | 1898 | 1924 | 1158 |
Swell 2 Height (m) Direction Period (s) | — | N 8 | NNE 11 | ENE 9 | W 11 | W 11 | WNW 11 | WNW 11 | W 12 | W 12 | ENE 8 | ENE 8 | ENE 8 | ENE 9 | ENE 8 | ENE 9 | ENE 9 | ENE 9 | ENE 9 | ENE 9 | ENE 9 |
| kJ | — | 5 | 11 | 73 | 144 | 151 | 202 | 123 | 274 | 390 | 92 | 134 | 137 | 228 | 222 | 202 | 211 | 211 | 194 | 168 | 222 |
Swell 3 Height (m) Direction Period (s) | — | — | — | W 11 | ENE 9 | ENE 9 | ENE 9 | ENE 9 | NE 9 | ENE 8 | SE 9 | N 9 | NNE 10 | SE 10 | SE 9 | SE 9 | SE 10 | SE 9 | SE 9 | SE 9 | WSW 8 |
| kJ | — | — | — | 38 | 71 | 53 | 53 | 70 | 77 | 90 | 43 | 43 | 52 | 24 | 22 | 22 | 23 | 22 | 21 | 21 | 19 |
Wind waves Height (m) Direction Period (s) | SE 11 | S 11 | S 10 | SSE 9 | S 9 | S 8 | S 8 | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| kJ | 13667 | 9291 | 5006 | 1872 | 1138 | 643 | 476 | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 1271 | 1271 | 1271 | 1813 | 2051 | 10 | 0 | 0 | 0 | 0 | 2040 | 20 | 1813 | 1841 | 0 | 1284 | 1284 | 0 | 0 | 0 | 0 |
Best forecast wave conditions in Guam | |||||||||||||||||||||
Best forecast wave conditions in Guam | |||||||||||||||||||||
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)
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 Umatac 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 Umatac Surf forecast
The above surf forecast table for Umatac provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Umatac can be found by selecting the local surf guide option on the grey menu. Our Umatac 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 (Umatac) 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 Umatac 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.
Umatac is 22 km (14 miles) from Agana. If you plan a holiday in Guam, look for hotels and other accommodation in Agana. Agana has rooms for a wide range of budgets as well as car hire and transport links.
Nearest