About
Data sources, features, and how to read the display
Maui Wind Swell is a comprehensive ocean conditions forecast for Maui island. The site combines wind forecasts, tide predictions, and swell data to give you a complete picture of beach and water conditions. The Buoys page shows real-time observations from Pacific buoys with an interactive map.
Maui Wind Swell displays forecast data – predictions of future conditions based on weather models. Forecasts are useful for planning but may differ from actual conditions. Verify with live data before heading out:
Reading the Display
Wind
- Interactive map – Color-coded wind speeds across the island with animated playback through the day. Three rendering styles: smooth gradient, cartographic, and classic contour
- Today/Tomorrow toggle – Switch between today's and tomorrow's forecast
- Data type toggle – Switch between wind, swell, and tide views for each region
- Regional summaries – Quick-reference wind direction arrows and speeds for each region
- Hourly sparklines – Wind speed chart throughout the day with current hour highlighted
Tides
- Continuous curve – Shows tide height throughout the day
- High/Low markers – Labeled points indicate high and low tide times
- Current time indicator – Vertical line shows the currently selected hour
Swell
- Direction arrow – Shows where waves are heading (toward shore)
- Cardinal direction – Where the swell originates (e.g., NW = northwest swell)
- Height range – Wave face height in feet, color-coded by size
- Period – Time between waves in seconds, color-coded by quality
- Energy bar – Visual indicator of relative wave power
When significant, both ground swell and wind swell are shown separately.
Period Color Coding
Buoys
- Interactive map – Zoomable map showing all NDBC buoys with great circle routes to Maui
- Buoy cards – Click any buoy to zoom the map and see detailed swell components with region impacts
- Swell exposure windows – Clickable reference showing which swell directions can reach each region of Maui
- Travel time & ETA – Estimated arrival time for each swell component at each affected region
The Buoys page provides a real-time view of raw buoy observations, complementing the processed swell forecasts on the main wind map.
Week View
- 5-day outlook – Wind conditions for the next 5 days at a glance
- Regional sparklines – Per-region wind speed trend lines showing how conditions change across the week
- Morning & afternoon – Wind speed, direction, and arrows for each time of day
- Color-coded speeds – Same color scale as the main wind map
- Daily summary – One-sentence island-wide wind description per day
The Week page shows the 5-day wind outlook with regional sparkline trends. Click any data point on a sparkline to see the wind map for that time with the region highlighted.
Data Sources
Wind
PacIOOS ERDDAP – WRF Maui-Oahu 2km resolution forecast from the University of Hawaii. How it works →
Swell
3-tier blended forecast: nearshore buoy observations (NDBC/CDIP), deep-water spectral buoys propagated via group velocity (NDBC), and WaveWatch III model forecasts (PacIOOS/University of Hawaii) for extended 5-day outlook. How it works →
Tides
NOAA CO-OPS – Tide predictions from Kahului Harbor, Kihei, Lahaina, and Hana stations. How it works →
Coastline
Hawaii Statewide GIS Program – Coastline geometry for the wind map and buoy page.
Special Thanks
Mahalo to GP's Maui Surf Report for introducing us to the UH WRF wind maps. If you're looking for Maui's best daily surf report, check out GP's blog.
Install the App
Add Maui Wind Swell to your home screen for quick, app-like access. On Chrome or Edge, look for the install icon in the address bar. On iOS Safari, tap the Share button then "Add to Home Screen".
Contact
Questions, comments, or suggestions? Email mauiwind@technicallyhawaiian.com