How the plan works.
One number per hour, per spot, for you. Here is what goes into it, how to read it, and what you can change.
The number is the answer
Every hour gets a score from 0 to 100: how well it fits you, at that spot. It weighs the wind against your own range, the gusts, how much the forecast models agree, the tide and the water, the wind direction and daylight.
Wind alone gets a spot to 85. Your rules lift it further: +12 per Preferred rule met, +10 Required, +6 Bonus, up to 100. More rules met ranks higher.
- 55Doable from 50
- 70Good from 65
- 84Epic from 80
Every number is yours. Tap an hour on a spot's day and it shows why it scores what it does: wind in range, gusts, models, tide, rule points and caps, each with its number. Every one of those numbers can be changed on You: switch Expert on and they are under Expert numbers. Change one and every spot follows; the defaults are what most riders want.
Under 50 is Poor, under 30 No go. Today and tomorrow puts the best spot on top: of the spots that clear your bar, the best band first, then the most rules met, then the score. A window is a stretch of hours that score well together.
- 1Your spot84Epic
- 2Another spot71Good
- 3A third spot55Doable
Read an hour
Each spot has a strip, one cell per hour of daylight. The colour is the wind: the stronger, the warmer. The thin band on top is the gust, in its own colour. The number is the forecast wind in knots, the smaller one under it the gust.
Wind is what you feel: the forecast wind plus a share of the gust that depends on the sport: 40% for kites, 20% for foil, wing and windsurf, 15% for parawing. Rules, your range and the sizes all use it. So 13 kn with gusts of 24 is 17 kn on a kite and 15 kn on a wing, and a rule "Wind at least 15 kn" is met for both. The colour shows it too.
The arrow under each hour points where the wind blows to. Wind from SW, the arrow points NE. Directions are always compass points. The line under the strip is the tide, at spots with a tide.
The week grid reads the same way, one cell per day: the strongest daylight wind, its colour, the arrow, and in the corner the day's best score for you. Tap a day for its hours.
- Colour = the wind
- Band on top = the gust
- Arrow = where it blows to (here wind from SW)
- Line under it = the tide
Rules and how much they count
A rule is what a spot needs: a falling tide, wind from SW to NW, above 110 cm. Each rule has a weight. Directions are a rule too: "Rideable from" and "Ideal from" in the spot's direction picker.
- Required
- Not met: the hour is a No go.
- Met: +10 points.
- Preferred
- Not met: nothing changes.
- Met: +12 points.
- Bonus
- Not met: nothing changes.
- Met: +6 points.
On any spot's Settings, a rule's Use my own numbers sets its own cap and bonus.
The bar and the ceiling
Go from
The bar: worth the drive
From which score a spot is worth going to: Doable, Good or Epic. It follows the drive time first: up to 20 minutes away, Doable is enough; up to an hour, Good; further, Epic. Change it whenever you like. A spot that is on but under its bar still shows, marked Below their bar, and its email stays quiet.
Best
The ceiling: at its best
How good this spot gets on its best day. A flat lake is rarely Epic; a tidal spot with its rules met can be. The ceiling caps the score: Good at its best stops at 79, Doable at 64. It never raises a score, and the bar never sits above the ceiling.
On the spots list both read as one line, for example "35 min · from Good · best Good".
Expert
One switch on You, Expert, off by default. Switched on, Expert numbers shows every number the plan uses, yours to change: rule points, gust and model weights, session hours, every tuning value. The rule editor then also offers “Use my own numbers”. The defaults are what most riders want. A change applies to every spot. The numbers sit in groups, closed until you open one, with a search box to find one by name. Each number says what it does with an example in real numbers, which screens it changes, and what it does to a sample hour you set yourself. Three presets fill in a few numbers at once to start from.
- Session hours. The earliest start and the latest finish of a session day, for every spot. Hours outside score 0 and never make a window.
- Wind and gusts. How much the gusts count as power and when a gusty day costs points. Changes the colour of every hour, the wind in range and the size you are told to take.
- Models. How much it costs when the forecast models do not agree: your agreement weight times the two costs. Changes the score of every hour where the models differ.
- Sizing. How the ideal size is worked out and picked from your quiver, and what wrong gear costs. Changes the size you are told to take and the score when your gear does not fit.
- Tide and daylight. What each tide band keeps at spots with tide bands, and when the session day starts and ends. Changes the score of the hours on those bands and which hours count at all.
- Rules and points. How high wind alone goes, what your rules add or cap, and what counts as a window. Changes the score of every hour, the rule points and the windows; a rule with its own numbers keeps them.
- Surf. How wave height, period, the faces of the break and the wind on the water count for surf. Changes the score of every surf hour, on the board, the week and the alerts.
Where the data comes from
- Wind: six model runs through Open-Meteo (CC BY 4.0), five weather models plus its own best match. When they disagree, the plan says so instead of averaging it away.
- Dutch tides: Rijkswaterstaat (CC0), the astronomical tide plus their surge forecast. Elsewhere the tide is a sea-level curve until you add your own window; the Paje lagoon is calibrated on timed beach observations.
- Live wind from Rijkswaterstaat's Matroos wind poles, the nearest one within 15 km of your spot: 10-minute readings that arrive 30 to 40 minutes behind, speed and a compass point, no gusts. A reading older than 60 minutes is not shown as live.
- Known spots: pick one of 318 spots from the list when you add a spot, and its name, pin, time zone, tide and sports are filled in. Spot locations: © OpenStreetMap contributors (ODbL), Wikidata (CC0).
- Honestly: forecast models are often a few knots off, and they can miss a sea breeze or a shower. It is a forecast, not a promise. Look at the water before you rig.
Something wrong?
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