Australia's vast coastline spans tropical to sub-Antarctic conditions, from the Great Barrier Reef to the Southern Ocean — requiring specialized marine forecasts for each region.
Australia has the longest coastline of any single nation used for marine recreation — from tropical Queensland to the wild coast of Tasmania. Conditions vary enormously between regions, and a forecast for the protected waters of Sydney Harbour bears no resemblance to the open Southern Ocean off Victoria.
The Great Barrier Reef supports a massive tourism industry where wind, wave, and visibility directly determine daily operations. Hundreds of commercial vessels operate on the reef every day, and even moderate wind shifts can shut down outer reef trips while inner reef locations remain calm.
Bass Strait between Victoria and Tasmania is one of the roughest stretches of water in the Southern Hemisphere. Shallow waters amplify Southern Ocean swell, and wind funnelling between the mainland and Tasmania creates steep, confused seas that challenge even large commercial vessels.
The Sydney to Hobart yacht race is one of the world's premier offshore events, with conditions that range from calm to survival-level. For developers building marine applications for Australian waters, understanding the dramatic differences between regions is essential.
Long-period swell from the Roaring Forties generates massive seas along the south coast and through Bass Strait.
November through April brings cyclones to the northern coast, with rapid intensification over warm waters.
A warm boundary current along the east coast that affects wave patterns, vessel drift, and fishing conditions.
Northern waters see tidal ranges up to 10+ metres (Kimberley coast), creating powerful currents.
Here's how to get an AI-powered marine weather forecast for Sydney Harbour — one of the most iconic sailing destinations in the world:
curl -X POST https://api.sealegs.ai/v3/spotcast \
-H "X-API-Key: your_api_key" \
-d '{
"latitude": -33.8688,
"longitude": 151.2093,
"start_date": "2026-01-20",
"num_days": 3,
"vessel_info": {
"type": "sailing",
"length_ft": 40
}
}'{
"summary": "Great conditions for a 40ft sailing vessel in Sydney
Harbour. Northeast sea breeze building to 15-18kt in the
afternoon, typical summer pattern. Seas 1-2ft inside the
harbour, building to 3-5ft outside the heads. Long-period
south swell (12-second) from the Southern Ocean wrapping
around the coast. Excellent racing conditions. Note:
conditions outside the harbour are significantly rougher
than inside.",
"daily_forecasts": [
{
"date": "2026-01-20",
"classification": "Excellent",
"confidence": 0.92,
"wind_speed_kt": 16,
"wind_gust_kt": 22,
"wave_height_ft": 1.5,
"wave_period_s": 5
}
]
}Tip: Pass vessel_info to get forecasts tuned to your specific boat type. A 40ft keelboat handles 3ft harbour chop differently than a 16ft dinghy — the AI adjusts its recommendations accordingly.
The same request works for any Australian coordinates. Use -16.9186, 145.7781 for Cairns and the Great Barrier Reef, -37.8136, 144.9631 for Melbourne and Port Phillip Bay, or -42.8821, 147.3272 for Hobart, Tasmania.
The API returns a full set of marine weather parameters. For Australian waters, these are especially important:
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Rock lobster, tuna, and prawn fleets need accurate offshore forecasts for the Southern Ocean and Coral Sea. Build weather-aware trip planning for fleet operators and safety managers.
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Here are commonly used coordinates for Australian marine forecasts:
-33.8688, 151.2093-16.9186, 145.7781-20.2633, 148.9536-37.8136, 144.9631-32.0569, 115.7439-42.8821, 147.3272-28.0167, 153.4000Get your free API key and start integrating AI-powered marine forecasts for Australia into your application.