No race selected
| Boat | SOGkn | VMCkn | DTWnm | ETA | Δ vs menm | 5′ | 15′ | Age |
|---|
Event log
Measured now
| Model | Windkn · Δ | Gustkn · Δ | Dir° · Δ | Score | Updated |
|---|---|---|---|---|---|
| No models selected — choose models in Setup → Weather models. | |||||
Δ = forecast − measured. Score ranks the selected models against each other by recent agreement with your B&G instruments at this position (wind, gusts, direction). Higher is better — but it reflects skill here, now, not necessarily downstream where you're routing to.
Rolling accuracy
| Model | Wind biaskn | RMSEkn | Gust biaskn | Dir bias° | Dir RMSE° | n |
|---|---|---|---|---|---|---|
| No comparison cycles recorded yet. | ||||||
Bias = mean signed error (a steady offset across all models usually means instrument calibration, not the model). Forecast snapshots stored for future lead-time scoring: 0.
Choose which models to rate, and tune the comparison, in Setup → Weather models.
Corrected leaderboard
Corrected = (elapsed + projected time to finish at current VMC) × ToT. Finished boats use their actual elapsed. Lower is better; ratings in Fleet.
| # | Boat | Mark | DTWnm | To finnm | SOGkn | VMCkn | ToT | ETA fin | Corrected |
|---|
Replay
| Boat | SOG | VMC | DTW | Mark |
|---|
Races
My boat
Competitors
Scan nearby AIS
Listens to all AIS traffic around your current position and lets you add the closest vessels as competitors — useful on the start line.
Connection
Position source for my boat: AIS (own MMSI) and/or this device's GPS — set in "Edit my boat".
Weather models
Pick which models to pull and rate against your B&G instruments (Weather tab). Global models always cover you; regional high-res models appear only when you're inside their domain.
Weather comparison
ⓘ How the height correction works
Weather models report wind at the standard 10 m reference height. Your anemometer sits at the masthead (e.g. 20–28 m), where the wind is stronger because of the vertical wind gradient (shear) over the sea. Comparing the two raw values would blame the model for what is really a height difference.
When enabled, both the base wind (window mean) and the gust (window max) are scaled down to their 10 m equivalent using the power-law profile:
V₁₀ = Vmast × (10 / H)α
H— anemometer height above water (the field below)α = 0.11— power-law exponent for neutral open-sea conditions
Wind direction is not adjusted — veer with height is small. The same factor is applied to base and gust, before any model comparison or scoring.
Example at H = 28 m: factor = (10/28)^0.11 ≈ 0.891, so 13.0 kn at the masthead → 11.6 kn at 10 m. Lower mast → smaller correction; at H = 10 m the factor is 1.0 (no change).
Note: this is a single-exponent approximation; it ignores atmospheric stability and is a first-order fairness adjustment, not an exact boundary-layer model.
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Data
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