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Surf Forecasts:
Portsea Back Beach surfForecast / VIC – Mornington Peninsula / Australia
48hr Weather and Surf, issued 4 am Wednesday 17 Dec 2025 AEDTForecast update in hr min s Forecast update imminent
Portsea Back Beach surf forecast is for near shore open water. Breaking waves will often be smaller at less exposed spots.
Today's Portsea Back Beach sea temperature is
15.9° C
(Which is normal for this time of year)How big are the waves at Portsea Back Beach today?
The current surf forecast for Portsea Back Beach at 8AM is: 1.2m 10s primary swell from a Southwest direction and 0.3m 16s secondary swell from a Southwest direction (forecast issued at 04:00am December 17). The wind direction is predicted to be offshore and the swell rating is 2.
| Time (AEDT) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (17 Dec) | 4ft (1.2m) | 10s |
| Afternoon (17 Dec) | 3.5ft (1.1m) | 10s |
| Evening (17 Dec) | 3ft (0.9m) | 10s |
Table - waves today at Portsea Back Beach. (Swell directed towards the surf break)
Updates in hr min s Forecast update imminent
Wednesday 17 | Thursday 18 | Friday 19 | ||||||||||||||||||||||
| 2 AM | 5 AM | 8 AM | 11 AM | 2 PM | 5 PM | 8 PM | 11 PM | 2 AM | 5 AM | 8 AM | 11 AM | 2 PM | 5 PM | 8 PM | 11 PM | 2 AM | 5 AM | 8 AM | 11 AM | 2 PM | 5 PM | 8 PM | 11 PM | |
Rating (10 max) | ||||||||||||||||||||||||
Swell Height Map |    |    |    | |||||||||||||||||||||
| Wave Height (m) & direction (?) | ||||||||||||||||||||||||
| Period(s) (?) | 11 | 11 | 10 | 10 | 10 | 10 | 10 | 9 | 9 | 10 | 10 | 10 | 11 | 11 | 11 | 13 | 13 | 12 | 12 | 12 | 12 | 11 | 11 | 11 |
Wave (?)Graph  | ||||||||||||||||||||||||
 kJ (?) | 471 | 361 | 302 | 265 | 226 | 170 | 167 | 106 | 84 | 108 | 136 | 156 | 198 | 153 | 155 | 173 | 320 | 252 | 248 | 240 | 224 | 213 | 150 | 142 |
Wind (km/h) | ||||||||||||||||||||||||
| Wind State (?) onshore cross-onshore cross-shore cross-offshore offshore glassy | cross- off | cross- off | off | cross- off | cross | cross- on | cross | cross- on | cross- on | glass | cross- off | cross- off | cross- on | cross | cross | cross- off | cross- off | off | off | off | cross | on | cross- on | on |
High Tide / height (m) | 9:14AM 1.20 | 11:19PM 1.22 | 10:05AM 1.17 | 12:18AM 1.28 | 10:59AM 1.15 | |||||||||||||||||||
Low Tide / height (m) | 3:35AM 0.81 | 4:10PM 0.36 | 4:47AM 0.85 | 5:03PM 0.33 | 6:01AM 0.84 | 5:53PM 0.28 | ||||||||||||||||||
Wednesday 17 | Thursday 18 | Friday 19 | ||||||||||||||||||||||
| Sunrise | - | - | 5:52 | - | - | - | - | - | - | - | 5:52 | - | - | - | - | - | - | - | 5:52 | - | - | - | - | - |
| Sunset | - | - | - | - | - | - | 8:40 | - | - | - | - | - | - | - | 8:42 | - | - | - | - | - | - | - | 8:43 | - |
 | |  | | | | | | | | | | | |  |  |  | | |  | | |  | | |
Rain (mm) | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 1 | - |
| Temp. °C | 12 | 12 | 12 | 18 | 27 | 24 | 22 | 22 | 20 | 19 | 19 | 27 | 21 | 24 | 24 | 23 | 21 | 21 | 22 | 26 | 26 | 22 | 20 | 18 |
| Feels °C (?) | 11 | 11 | 11 | 17 | 24 | 19 | 19 | 19 | 19 | 19 | 17 | 25 | 16 | 21 | 22 | 21 | 19 | 19 | 19 | 23 | 23 | 17 | 19 | 15 |
- Map Icons:
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Live Wave Height (m)
Live Wind Speed (km/h)
Surf Rating (10 Max)
Ocean Swells (m)- Wind Speed (km/h)
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