Melbourne · Victoria, Australia

Port Phillip Bay Marine Forecast

Updated Fri Sep 11, 2026

Calm Fri-Sat boating, choppy Sunday midday winds

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Marine Forecast for Port Phillip Bay Sep 11–13, 2026

📋 Calm Fri-Sat boating, choppy Sunday midday winds

FriSep 11GO

Light 2-7 knots winds and calm 0.6-1.0 feet seas at long 7-12s periods from the SSW make Friday an excellent, comfortable day on the water with no bad stretches.

SatSep 12GO

Light winds (1-9 knots) and small 0.5-0.8 feet seas keep Saturday comfortable and safe throughout, with only a slight wind and chop increase by evening.

SunSep 13CAUTION

Winds build to 18-19 knots (gusts 26 knots) from the N between 10:00 AM-2:00 PM, whipping up steep, short-period 2.5-2.8 feet chop - use caution and avoid this midday window, favoring morning or evening instead.

Friday and Saturday offer excellent, calm boating with light winds and gentle long-period swell. Sunday sees building north winds and short-period wind-waves that create a steep, choppy sea mid-morning through early afternoon, warranting caution.

-38.1000, 144.7800 · Updated Fri Sep 11, 2026 · Model confidence and timing windows come from the same AI forecast engine as the SeaLegs AI app.

Recent days at Port Phillip Bay

Fri9/4NO-GO
Sat9/5NO-GO
Sun9/6GO
Mon9/7CAUTION
Tue9/8GO
Wed9/9NO-GO
Thu9/10GO

Today’s Water at Port Phillip Bay

Sea surface temperature and chlorophyll around Port Phillip Bay, imaged fresh every morning. Water at the star is 55.5°F today, and chlorophyll of 2.57 mg/m³ reads as nutrient-rich green water at the spot.

 Imagery: Sep 10, 2026 · rebuilt every morning
Port Phillip Bay sea surface temperature chart, Sep 10, 2026 — 55.5°F at the spot with labeled depth contours
Sea surface temperature. Warm colors are warmer water; tight color gradients are temperature breaks. Labeled depth contours — bold at 100 / 500 / 1,000 fathoms — draw the bottom structure.
Port Phillip Bay chlorophyll chart, Sep 10, 2026 — water color and bait edges
Chlorophyll. Green is nutrient-rich shelf water, deep blue is clean offshore water — the edge between them is where bait tends to stack, and today reads 2.57 mg/m³ (nutrient-rich green water) at the spot.

These charts show you the breaks. DeepCast reads them. A zone-by-zone AI fishing report for these exact waters — temperature edges, color changes, and structure, analyzed together — for $4.99.

Get the AI fishing report

SST and chlorophyll from the SeaLegs AI DeepCast satellite pipeline. Charts are a planning aid — always check the official marine forecast before making the run.

About Port Phillip Bay

Port Phillip Bay is a big enclosed sheet of water, and that changes everything about how you read it. There's no ocean swell rolling in here — the sea state is wind-driven chop, and the bay's short fetch means it stands up steep and nasty the moment the breeze pipes up. A morning glass-off can become a genuinely uncomfortable ride home by early afternoon when the sea breeze fills in.

This page updates daily with a 3-day outlook built around what actually matters in the bay: wind strength and direction, how the chop will build through the day, and when the water lays down. Each day gets a plain GO / CAUTION / NO-GO rating — the same AI rating used in the SeaLegs AI app.

Reading conditions in Port Phillip Bay

Watch the wind, not the swell. The bay's limited fetch means chop builds fast and steep — a 15-knot southerly that would barely register offshore will have the bay standing up short and sharp within an hour, especially over the shallower northern flats off Melbourne and St Kilda. The classic trap is the afternoon sea breeze and the southerly change: a calm, fishable morning flips to a wet, banging slog once the change comes through, so plan your run home around it rather than the dawn conditions.

The other hard rule is the entrance. The Rip at Port Phillip Heads, between Point Lonsdale and Point Nepean, is one of the most dangerous stretches of water in the country — the tidal flow through the narrow gap stacks against wind and ocean swell into standing, breaking water that has killed experienced crews. It's only safe on the right tide (slack water) and the right wind, and this bay forecast does not cover conditions in the Rip itself. If you're heading out through the Heads, treat that passage as a separate, serious decision.

Port Phillip Bay forecast FAQ

How is the sea at Port Phillip Bay today?

As of Sep 11, 2026, the SeaLegs AI verdict for Port Phillip Bay is GO. Friday delivers excellent boating conditions all day with light 2-7 knots winds shifting from SW to SE and gusts staying under 9 knots. Seas stay calm at 0.6-1.0 feet with long 7-12 second periods from the SSW/SW, giving a smooth, well-organized swell that's comfortable for any recreational vessel. Wave period confidence is a bit mixed overnight but heights and winds are rock-solid stable, so this is a great day to be on the water any time.

When is the best time to fish Port Phillip Bay for snapper?

The famous snapper run fires up through spring and into summer, roughly October to December, when the reds move into the bay in numbers. On the water, the fish and the boating both favour the settled window before the afternoon sea breeze fills in — light early winds and a tide change are the classic combination. Whiting and squid hold through the warmer months too. Always check the daily GO / CAUTION / NO-GO rating before you commit: a good snapper tide isn't worth much if a southerly change is going to turn the bay into steep chop before you're back at the ramp.

How accurate is this Port Phillip Bay marine forecast?

The outlook is generated from the latest marine model data and rated GO, CAUTION, or NO-GO by the same AI engine used in the SeaLegs AI app. It's a planning aid, not a substitute for the official Bureau of Meteorology (BoM) marine forecast and any current warnings — always check those before heading out.

How often is this forecast updated?

The page is rebuilt every morning from the latest model run, and the SpotCast card refreshes live in your browser. The date stamp above the outlook shows exactly when it was last generated.

What do GO, CAUTION, and NO-GO mean?

GO means conditions are favourable for most recreational boats. CAUTION means marginal — manageable for experienced crews in capable vessels, but check the wind and sea timing closely. NO-GO means conditions are hazardous for small craft and the trip is best postponed.

Can I get a forecast like this for my own spot?

Yes. In the free SeaLegs AI app you can drop a pin anywhere on Earth — your local ramp, a favourite mark, or a spot well offshore — and get the same AI-rated marine forecast and trip planning.

What is the water temperature at Port Phillip Bay today?

As of Sep 10, 2026, the satellite-derived sea surface temperature at Port Phillip Bay is about 55.5°F, with chlorophyll around 2.57 mg/m³ (nutrient-rich green water). The SST and chlorophyll charts on this page are rebuilt every morning from the SeaLegs AI DeepCast satellite pipeline.

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