Slack Water – Port Phillip
Port Phillip & Western Port
Free · In‑App Purchases · Designed for iPad. Not verified for macOS.
New: 48-hour wind, gusts, storm risk and waves for both bays, worked out with the current, and wind-against-current alerts. Current and next slack stay free.
Slack water times and a tidal current map for Port Phillip — the Rip, the Heads and the southern Bay — and Western Port. And now the next 48 hours of wind, gusts, storm risk and waves, worked out with the current.
Through the Heads the tide runs at four knots and more, and slack lasts minutes. It turns at a different time at every site, and the run-in and run-out don't behave the same. Slack Water works it out site by site, on your phone, with no reception needed.
SLACK TIMES, SITE BY SITE
Port Phillip: the Rip, Lonsdale Wall, Pope's Eye, Portsea Hole, the Hurricane wreck, Portsea, Queenscliff, Blairgowrie and Rye piers.
Western Port: the Western Entrance, Cowes and Stony Point jetties, San Remo bridge and jetty. See the turn, and the window when the current stays under your own limit.
CURRENT MAP OF BOTH BAYS
See where it's running and where it's slack: arrows, a colour map by speed, or animated flow.
YOUR OWN SPOTS AND TRACKS
Drop your marks on the map, or open a GPX file from your plotter, email or Files and pick the ones you want. Current and slack at each one. Hide spots from the map or keep only the ones you follow in the slack list. Record your track on the water and export it as GPX.
BUILT-IN MAP OF BOTH BAYS
Depth shading, contours every 5 m and, if you want it, the seabed type (sand, mud, seagrass, reef) and the banks that dry at low tide. All on your phone.
WIND, WAVES AND STORMS — NEXT 48 HOURS
Wind and gusts on the map and at every site. Waves in both bays and at the Rip, computed on your phone from the wind, the fetch, the depth, the tide and the current: wind against the ebb at the Heads builds a short, steep sea, and the map shows it. Storm risk from the atmosphere's instability. Checked against the five wave buoys in Port Phillip.
SLACK AND WIND-AGAINST-CURRENT ALERTS
Get a heads-up before slack at the sites you pick, and when 10 knots of wind or more will blow against the current. You choose how early.
MELBOURNE TIME, ALWAYS
Times are shown in Melbourne time, daylight saving included.
MADE FOR
Fishos, scuba divers, freedivers, snorkellers, kayakers and sailors crossing the Rip.
FREE
• Current right now, anywhere in Port Phillip and Western Port
• Next slack at every site and spot
• Your spots and GPX import/export
CURRENTS (PLAN AHEAD) — YEARLY SUBSCRIPTION
• Any day, any time: plan tomorrow's trip tonight
• Full-day current curve and every slack window
• Three-day current map
• Slack alerts
COMPLETE — YEARLY SUBSCRIPTION
Everything in Currents, plus the next 48 hours of:
• Wind and gusts, on the map and at every site
• Waves in both bays and at the Rip, with the current
• Storm risk
• Wind-against-current alerts from 10 knots
Subscriptions renew every year unless cancelled at least 24 hours before the end of the period. Manage or cancel it in your App Store account settings.
PLANNING AID ONLY — NOT FOR NAVIGATION
Current predictions are astronomical tide only (no wind, swell, rain or river flow), from simplified models of each bay, averaged over the depth; times are approximate. Wind, gusts, storm risk and offshore swell come from the NOAA GFS global model (25 km): local effects such as sea breezes are not resolved, and storm risk is not a warning. None of this is official: the references are the Bureau of Meteorology tide tables, marine forecasts and warnings, and AHO charts. Always check conditions on site.
Terms: https://gansoft.ch/slackwater-terms.html
Privacy: https://gansoft.ch/slackwater-privacy-policy.html
Terms of use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
New Complete plan: the next 48 hours of wind, gusts, storm risk and waves for Port Phillip and Western Port, on the map and at every site. Waves are worked out with the tide and the current, so the steep sea of wind against the ebb at the Heads shows up.
New alert: 10 knots of wind or more against the current at the sites you follow.
The Plan Ahead subscription is now called Currents; nothing changes for subscribers.
The developer, GanSoft SARL, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- GANSOFT SARL
- Size
- 25.9 MB
- Category
- Weather
- Compatibility
Requires iOS 15.0 or later.
- iPhone
Requires iOS 15.0 or later. - iPad
Requires iPadOS 15.0 or later. - iPod touch
Requires iOS 15.0 or later. - Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- Complete $24.99
- Plan Ahead $12.99
- Copyright
- © 2026 GANSOFT SARL
