# Why PulveCast exists > PulveCast is built by independent developer Renan Rafael Bertoldo in Brazil. Learn why the app exists, how the spray verdict is computed from Delta T, drift, inversion and wind, and which data providers it relies on. - Canonical URL: https://pulvecast.web.app/about - HTML version: https://pulvecast.web.app/about - Language: en - Last updated: 2026-09-12 - Site guide for agents: https://pulvecast.web.app/llms.txt Spray operators already know what Delta T is. What they do not have is one screen that checks every agronomic limit against a real forecast for the exact hour they are about to work. ## The problem A generic weather app tells you it will be 28 °C with 12 km/h of wind. It will not tell you that at that temperature and humidity your Delta T is above 10 and half of a fine-droplet application will evaporate before it reaches the canopy. It will not warn you that at 05:40 the air 80 metres up is warmer than the air at 10 metres, so your spray will hang in an inversion layer and drift somewhere you did not choose. PulveCast was built to close that gap, first for agricultural drone operators and then for tractors and uniports. ## How the verdict is computed For the selected location and hour, the app evaluates every parameter it has against the limits configured for your equipment, crop and nozzle. Each parameter returns green, yellow or red; the overall verdict is the worst of them. Nothing is hidden: tapping any card shows the value, the threshold it was compared against, and what that parameter does to an application. - Delta T is derived from dry-bulb temperature and relative humidity. The default ideal window is 2 °C to 8 °C. - Relative humidity is checked against a configurable band, 55 % to 90 % by default: below it droplets evaporate, above it the product runs off. - Spray drift risk crosses wind speed with the droplet class of your nozzle, from Very Fine to Ultra Coarse. - Thermal inversion is estimated from the Open-Meteo 80 m and 10 m temperature pair only, so both readings come from the same model. The default alert threshold is a 1.5 °C difference. - Wind speed and gusts are compared with your equipment ceiling — automatic for the supported agricultural drone models. - For aerial equipment only, the Kp index and the visible GPS, GLONASS, Galileo and BeiDou counts are checked, because geomagnetic storms and poor satellite geometry degrade RTK accuracy. ## Data providers - [Open-Meteo](https://open-meteo.com/) — Default provider: 7-day hourly forecast, wind by altitude, the 10 m / 80 m temperature pair used for thermal inversion, geocoding and time zone. - [WeatherAPI](https://www.weatherapi.com/) — Alternative 3-day forecast for Pro subscribers, completed with Open-Meteo for the remaining days. - [Apple WeatherKit](https://developer.apple.com/weatherkit/) — Alternative forecast of up to 10 days for Pro subscribers, requested through a server-side proxy so the credentials never reach the app. - [GFZ Potsdam](https://spaceweather.gfz-potsdam.de/) — Planetary Kp index — geomagnetic activity that degrades GNSS and RTK accuracy. - [CelesTrak](https://celestrak.org/) — Orbital elements for the GPS, GLONASS, Galileo and BeiDou constellations, used to compute satellite visibility at your coordinates. - [OpenStreetMap](https://www.openstreetmap.org/) — Base map and restriction zones for the safezone map. ## What PulveCast is not It is not an authorisation to fly or to spray, not a substitute for the product label, and not a replacement for measuring conditions at the field. A forecast is a model output; wind in particular changes fast near obstacles and terrain. Treat the app as a planning and go/no-go aid, and confirm on site. ## Who builds it PulveCast is developed and maintained by Renan Rafael Bertoldo, an independent software developer in Brazil, who also builds Drone Weather Forecast. There is no company behind it, no investor, and no advertising business model — which is why Pro exists. Contact: renan10r_@hotmail.com --- Other languages: [Português (Brasil)](https://pulvecast.web.app/pt/about) · [Español](https://pulvecast.web.app/es/about) · [Français](https://pulvecast.web.app/fr/about) · [Deutsch](https://pulvecast.web.app/de/about) · [Italiano](https://pulvecast.web.app/it/about) · [Nederlands](https://pulvecast.web.app/nl/about) · [Polski](https://pulvecast.web.app/pl/about) · [Bahasa Indonesia](https://pulvecast.web.app/id/about) · [Русский](https://pulvecast.web.app/ru/about) · [日本語](https://pulvecast.web.app/ja/about) · [Türkçe](https://pulvecast.web.app/tr/about) · [Ελληνικά](https://pulvecast.web.app/el/about) · [简体中文](https://pulvecast.web.app/zh-hans/about) · [繁體中文](https://pulvecast.web.app/zh-hant/about) PulveCast is a mobile application; this site is its product page and has no public HTTP API. Machine-readable index of this site: https://pulvecast.web.app/llms.txt · https://pulvecast.web.app/llms-full.txt