Heights are above ground level (AGL), following the terrain.
What runs where
All the processing — the terrain model, the WindNinja solver, the weather and search lookups — happens on our server. Your browser only draws the map and the results it's sent back. Nothing about terrain, wind physics or weather data is computed on your device. Want the physics and the pipeline? See How it works.
The three ways to start
Simulate: you choose the wind speed and direction yourself. Current conditions: we pull live weather for the area and use that. Forecast: a weather model (GFS/HRRR/NAM, depending on coverage) drives the wind over the next several hours, with a time slider to step through it.
Reading the wind (Flow view)
Streamlines and particles are on by default — they show the wind actually moving into, around and over the terrain, not just a wall of arrows. Turn on Arrows for a classic direction-at-a-glance view, or Rising/sinking air to see where the terrain itself is pushing air up (orange) or down (blue). Every layer has its own on/off and opacity in the Layers window. The Cross-section tool (X) draws a line and shows terrain plus wind vectors at each reported height along it, so you can see a ridge speeding the wind up and the lee side sheltering it.
Solver & structures
The Fast solver (mass-conserving) treats a structure as raised terrain — it's quick, but doesn't model wakes. Use a mesh finer than the structure itself so it isn't lost between grid points. The High-fidelity solver (momentum/OpenFOAM) actually models air flowing around and behind a shape — pick it for buildings, walls or anything where you care about the wake, not just the upstream speed-up.
Selecting, editing and deleting
Clicking something (the drawn area, a line, a point, a structure) selects it — it does not move it. Press V (or the status strip's "Edit" button) to enter Select/Edit and drag its handles; Esc returns to plain panning. With something selected, Delete (or the status strip's red button) removes just that object. "Clear… → Clear everything" removes everything.
Keyboard
- D — draw an area
- S — add a structure
- P — probe a point
- M — measure distance
- X — cross-section (terrain + wind vectors along a line)
- L — toggle the Layers window
- V — select / edit the current selection
- R — run
- / — search
- Esc — exit the current mode
- Delete — remove the current selection
API (for developers & AI agents)
The public JSON API lives under /api/v1 — no auth, no
key. GET /api/v1/capabilities documents current limits
and supported options machine-readably (also linked from this
page's <head>). POST /api/v1/jobs starts
a run; GET /api/v1/jobs/{id} polls it. See
/llms.txt for a plain-language summary meant
for language models, and Credits for
where the model and its data come from.