Weather routing for sailors
Compare weather forecasts for your course, explore route choices, and prepare a passage plan. WX Navigator shows the forecast used for each route so you can see where the models agree and where they differ.
Models compared
6
Finest heading step
1°
Forecast window
16 d
Re-route cost
Free
Compare forecast routes
WX Navigator routes every wind model available for your plan, course, and forecast window. It opens on the consensus track and identifies its model.
Step through the routes to compare their tracks and predicted finish times.
When routes differ, the chart shows where they separate so you can compare the choices before the start.
Departure-time scans solve the course from up to 24 starts and show the resulting finish times.
Turn on the isochrone bands to display the frontier reached at each search step.
Forecast data for your route
WX Navigator requests a corridor for the course and shows which forecast cycle and source it used. Availability, coverage, and freshness vary by model and location.
WX Navigator downloads a compressed corridor around the water your route could cross, at the steps needed for the search. A coastal-race download is typically a small fraction of a megabyte.
Reuse the downloaded data to test different starts, search settings, or course changes within its coverage and forecast window.
Currents come from the NOAA model that resolves your water — SFBOFS inside San Francisco Bay, the lake models on the Great Lakes, RTOFS offshore — at hourly steps.
NOAA GFS
0.25°Global. Four cycles a day.
NOAA HRRR
3 kmUS coasts and the Great Lakes. Hourly.
NOAA NAM
3 kmThe same US footprint as HRRR, from a different model core.
ECMWF IFS
0.25°Global. The European model.
ECMWF AIFS
0.25°ECMWF's AI forecast system.
NOAA OFS
TidesHourly tidal currents from thirteen coastal and Great Lakes models.
NOAA RTOFS
CurrentsSet and drift on the open ocean.
NOAA GFS-Wave
WavesWave forecasts for route comparison and wave-height limits.
GEBCO + ENC
DepthDepth data for draft and clearance limits.
Test route sensitivity
Compare eleven route calculations using 90 to 110 percent of your polar speeds and 90 to 120 percent of the forecast wind.
Each matrix cell shows the change in predicted finish time. When a route differs from the baseline, the panel gives the time and position where the tracks first separate and overlays the alternative on the chart.
Use the matrix to identify the wind speeds and places where routes diverge. It runs in your browser against the forecast already downloaded, with no further network request.
Use race mode on the water
Use a phone, GPS fix, and the share link for the route you planned ashore.
Open the route, take a fix, and name the mark you still have to round. Race mode solves the rest of the course from the boat's current position and returns a heading, upcoming tacks and gybes with their times, and a predicted finish.
Race mode solves ashore and sends a small readout to the boat. Re-route from a fresh fix when conditions change, or set it to re-route on a timer.
Set wave and depth limits
Set a wave ceiling to exclude water above it, or prefer calmer water when comparing routes.
A wave ceiling excludes water above the limit from the route. A calmer-water preference lets the search favor lower sea state when comparing routes.
Every candidate reports its highest sea state, average sea state, and hours above two and a half metres. Set your draft and a depth margin to exclude water that does not meet them.
Choose a boat polar
Search your ORC certificate by sail number and the VPP polar comes with it. Or paste your own measured polar.
Import a polar in matrix CSV, TSV, .pol, or Expedition or PredictWind
angle-speed format. The format is detected automatically.
A pasted polar is temporary unless you explicitly save it to your private account. Shared routes carry the track and a digest, never the speed table that produced them.
Plans and forecast limits
Route calculations are unlimited on every plan. Plans set course length, forecast duration, and available models.
| Plan | Course | Duration | Resolutions | Price |
|---|---|---|---|---|
| Anonymous | 60 nm | 24 h | Automatic Standard | Free |
| Free | 150 nm | 48 h | Automatic Standard | Free |
| Credits | Any passage | 16 days | Automatic All-out | $15 / 10 forecasts |
| Pro | Any passage | 16 days | Automatic All-out | $79 / year |
WX Navigator is a planning tool, not a navigation system. See the terms and the data attributions.
About WX Navigator
WX Navigator is an Upwelling planning tool for sailors who want to inspect the assumptions behind a route.
A route uses an isochrone search in the browser. Boat performance comes from an ORC certificate, a polar table you provide, or an account-saved polar. See the reference docs for setup and data details.
Upwelling also publishes Saildex results and hosts regattas. For Graham's sailing projects, visit Upwelling.