Calculate the tendency and trend of a barometer for a one to three hour period including barometric weather predictions.
- Tendency and trend of the barometer for the last hour or three hours (
FALLING|SLOWLY) - Prediction of weather and systems:
- By pressure trend only (
Expect gale force weather') - By pressure trend, thresholds and wind direction (
Increasing rain, clearing within 12 hours.) - By seasonal pressure thresholds for winter and summer (
Cloudy and humid, thunderstorms) - Front system tendency for the last three hours (
Falling before a lesser rise|Cold front passage|Strong and gusty, then veers) - Force wind expectation in Beaufort scale based on the pressure tendency (
F8-9)
- By pressure trend only (
- Detects current pressure system
Low,Normal,High
Note
- Picks the period with the highest severity (one hour or three hours)
- All calculations corrected (internally) to sea level pressure by optional
altitudeandtemperature - Up to 48 hour history
npm i barometer-trend
const barometer = require('barometer-trend');
barometer.addPressure(datetime1, 101500);
barometer.addPressure(datetime2, 101505);
barometer.addPressure(datetime3, 101512, 100, 20, 225); //100 = altitude, 20 = C degrees, 225 = wind direction
//barometer.addPressure(...) is more precise when pressure is corrected by altitude and temperature.
let forecast = barometer.getPredictions(); //returns JSON
- Pressure must be input in Pascals, 1015 mBar/hPa = 101500 Pascal.
getPredictions()investigate the trend for the latest one hour and three hours- If run less than one hour or three hours, the latest timing up until now is picked.
- The most recent trend with the highest severity is chosen (One hour or Three hour reading)
Feel free to contribute; create an Issue, and Pull Request including test code.
- All calculations is done by online research; the author of this library does not have a background in metereology. All sources listed below.
- A barometer is only one source of weather information and may give a general trend and indication, but not "see" the overall picture. (There's a reason satelittes exists and being a metereologist is a paid job.)
- All calculations presumes being located at sea with no disturbances.
- Near land, winds may be one-two Beaufort scale numbers lower and the wind might be coming from "the wrong direction".
- In subtropic and tropical regions some of the calculations may not be valid at all; i.e. the trade winds (easterlies) is different from northern hemishpere west->east (westerlies) low pressure systems.
- In trade wind zones observe the daily variations; any change to this pattern could possibly indicate gale weather.