#heat-index

Feels-like (apparent) temperature meteorology as an API, computed locally and deterministically. The wind-chill endpoint computes how cold the air feels when wind carries body heat away, using the Environment Canada formula WC = 13.12 + 0.6215·T − 11.37·V^0.16 + 0.3965·T·V^0.16 from the air temperature (°C) and wind speed (km/h), valid at 10 °C or below with wind of at least 4.8 km/h. The heat-index endpoint computes how hot it feels in warm, humid air with the US National Weather Service Rothfusz regression from temperature and relative humidity, since high humidity slows sweat evaporation, with the low-/high-humidity adjustments. The apparent-temperature endpoint computes the Australian Bureau of Meteorology apparent temperature, AT = Ta + 0.33·e − 0.70·ws − 4.00, which combines the warming effect of humidity (through the vapour pressure e) and the cooling effect of wind (ws in m/s) in a single feels-like value. Temperatures are in °C (Fahrenheit also returned), humidity in %, wind in km/h for wind chill and m/s for apparent temperature. Everything is computed locally and deterministically, so it is instant and private. Ideal for weather, outdoor-activity, sports, smart-home and wearable app developers, comfort and safety tools, and meteorology education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is the feels-like temperature calculator; for the occupational WBGT heat-stress index use a WBGT API and for live weather observations a weather data API.

api.oanor.com/feelslike-api

Meteorological formulas as an API — the derived weather figures, computed from your own readings, with no data feed or key needed. The wind-chill endpoint gives the "feels like" cold using the Environment Canada formula in metric (°C, km/h) or the US NWS formula in imperial (°F, mph), and flags when the reading is outside the valid range. The heat-index endpoint gives the apparent temperature from heat and humidity using the NWS Rothfusz regression with the standard low- and high-humidity adjustments. The dew-point endpoint uses the Magnus formula to turn temperature and relative humidity into the dew point, and also returns the vapour pressure and the absolute humidity. The beaufort endpoint maps a wind speed (m/s, km/h, mph or knots) to its Beaufort force and description, or a force back to its speed range. Everything is computed locally and deterministically, so it is instant and private. Ideal for weather apps and dashboards, agriculture and HVAC, marine and aviation, and outdoor and safety tools. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 5 endpoints. This computes weather formulas from your own readings; for live forecasts and observations use a weather data API.

api.oanor.com/weathercalc-api