The go/no-go score turns the forecast into one of three labels for each hour: "Within your limits", "Marginal" or "Outside your limits". It runs seven weather checks against your drone profile, and the worst check decides. It is weather guidance only, not for air navigation, and it doesn't tell you whether you may fly somewhere: check your local rules.
The checks and their defaults
Wind percentages are of your drone's maximum wind resistance, as published by the maker and stored in your drone profile. Wind and gusts are read at the altitude you choose.
| Check | Within your limits | Marginal | Outside your limits |
|---|---|---|---|
| Sustained wind | ≤ 60% of the drone's max wind resistance | ≤ 85% | > 85% |
| Estimated gust | ≤ 80% | ≤ 100% | > 100% |
| Rain chance (drone without IP rating) | < 20% | < 50% | ≥ 50% |
| Temperature | inside the maker's range, 5 °C or warmer | below 5 °C (battery warning) | outside the maker's range |
| Visibility | ≥ 5 km | ≥ 1.5 km | < 1.5 km |
| Kp (latitude-weighted) | ≤ 4 | 5–6 | ≥ 7 |
| Daylight | day | civil twilight | night |
The worst check decides
Altiwind doesn't average the checks. If six are fine and one is "Outside your limits", the hour is "Outside your limits". An average would let a mild temperature and good visibility hide a gust over your drone's rating, and the gust is what you'd actually be fighting.
Example
You fly a drone rated for 10.7 m/s (38.5 km/h, 23.9 mph, 20.8 kn) and pick 120 m. The forecast for 3 pm:
| Check | Forecast | Result |
|---|---|---|
| Sustained wind | 27 km/h (70%) | Marginal |
| Estimated gust | 39 km/h (101%) | Outside your limits |
| Rain chance | 10% | Within your limits |
| Temperature | 12 °C | Within your limits |
| Visibility | 20 km | Within your limits |
| Kp | 3 | Within your limits |
| Daylight | day | Within your limits |
The hour shows "Outside your limits", and the gust chip tells you why. Drop to 60 m, or wait for the gusts to ease later in the afternoon, and the same view shows you whether that changes the answer. The gust forecast page explains where the 39 km/h comes from.
Reason chips
Every check shows as a reason chip, not just the one that decided the label. That matters because two "Marginal" hours can mean very different things. One might be marginal because it is civil twilight, the other because the wind is at 80% of your drone's rating. The chips let you see which, and how close the other checks are to tipping over.
For a quick check without opening the app, try the can I fly now tool.
FAQ
Does "Within your limits" mean I can fly?
No. It means the weather is within the limits set for your drone. Airspace, local rules and the conditions you see on site are yours to check before every flight.
Why is an hour "Marginal" when the wind looks fine?
Another check is deciding it. Look at the reason chips: common causes are civil twilight, a temperature below 5 °C (the battery warning), or a raised Kp index.
Which altitude does the wind check use?
The altitude you choose: 30, 60, 90 or 120 m. Wind and gusts usually grow with height, so the same hour can be "Within your limits" at 30 m and "Marginal" at 120 m.
Can I change the thresholds?
Not in the app. Altiwind uses the defaults in the table above, with the wind checks set as shares of your drone’s rating.