Calculate atmospherical pressure trend

i need to calculate atmosferical pressure trend, It’s a very basic funcion in cheap barometer.
I just have a sensor gave me pressure in mBar and i just have a persistence setup.
Someone can help?

Many thanks


Someting like this?

Hi, I just have grafana with graph of pressure.
For trend i mean, well: pressure is rising since three hours, so trend is rising…pressure is stop to rising and is stable since 2 hours, so is stable, pressure start to fall since 2 hour, so trend will be falling

I woult transform in text string the trend of the graph



I haven’t added this yet, but it is a goal for a binding I’ve written, called Weather Calculations. The binding attaches to channels containing measurements for things like atmospheric pressure, temperature and humidity, and generates a number of derived values. If you can wait a week or two, I should be able to add pressure trend.

There’s a version available for download here, and I’ll continue to post updates.


is there a dedicated topic to follow for this bindings?


This binding came about originally because of work I was doing to support the WeatherFlow SmartWeather station, so that’s where it was originally discussed. Of course that’s not very good for people who might like to use it with other equipment. I just created a new topic about it, along with some info for how to use it:

I have Netatmo station and RAW data into persistence. It would be great fo r binding to work with timeseries data from any device.


Yes, you should be able to use the Weather Calculations binding to get all of the derived values “for free”. It would be nice if it were possible to run all of the previous observations through the binding so that it was available for graphs, but I’m not sure offhand how one might do that.

Hi Marco,

I just made a new snapshot of the Weather Calculations binding that includes atmospheric pressure trend using the US National Weather Service trend definitions. It’s a simple implementation but it should work as expected. Feel free to have a look and let me know if I can answer any questions.


Hi @hww3,
Starting the bundle i got this errors:

Error executing command: Error executing command on bundles:
        Error starting bundle 1203: Could not resolve module: org.openhab.binding.weathercalculations [1203]
  Unresolved requirement: Import-Package: org.eclipse.jdt.annotation; resolution:="optional"
  Unresolved requirement: Import-Package: org.eclipse.smarthome.core.library.unit


Are you running openhab 2.3? I think the units support is new in that version, so that could be the source of the problem. I’m going to try setting up a new 2.3 install and see if the error happens there.

I use 2.2, this could be the problem.


Oh, yes, that’s almost definitely the problem. This version of the binding uses the new “Units of Measurement” support to ensure that values are displayed and calculated in the correct unit system.

Also, I just fixed/improved the sea level pressure calculation, so that it takes temperature into account. The previous method assumed a standard temperature of around 15C.