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Weather Software => Station Software Development => Topic started by: vonodna on June 20, 2017, 05:52:42 AM

Title: Help with a weather prediction algorithm based on air ressure and temp
Post by: vonodna on June 20, 2017, 05:52:42 AM
Hi!
I am working on a arduino based "weather station". It features e-Paper display and is based on a combined Adafruit sensor that gives atmospheric pressure, temperature and humidity. the goal is to replaced an old digital termometer/weather station that worked really well for some years but stopped working some time ago.
Disclaimer 1: I know that weather prediction is much much more than showing an icon of a sun or cloud based on simple local measurements. That is why we have satellites, super-computers, sophisticated weather stations, meteo-baloons, etc.
Disclaimer 2: I am fully aware that the public in this forum understands something different under the term "weather station". I just do not know any other name for these: things: https://www.amazon.com/Ambient-Weather-Wireless-Temperature-Barometer/dp/B00BQFWYF2/ref=sr_1_12?s=furniture&ie=UTF8&qid=1497951888&sr=1-12&keywords=weather+station
 (http://things: https://www.amazon.com/Ambient-Weather-Wireless-Temperature-Barometer/dp/B00BQFWYF2/ref=sr_1_12?s=furniture&ie=UTF8&qid=1497951888&sr=1-12&keywords=weather+station)

Still that little thing that I had (unlike the other two I have at home) worked pretty well as an input for my decision how to get dressed in the morning.
Up to now I understood that basically it is not the current pressure that is interesting for short-time prediction but rather the change in the pressure. And if it goes up the weather should be fine, if it goes down the chances for rain are higher.
What I am looking for is something more specific - algorithm, thresholds, values, parameters. How does all these digital thermometers /weather stations work? The only thing I found online are several sites with "Sager open-source algorithm" , but there is no description and the js source code is not exactly good at explaining the working principle.
So, can someone please point me to some online materials or explain about how to choose what is the coming weather based on the sensors I have?
Thanks!

P.S. If someone is interested in the device I am working on I am happy to share more details. 
Title: Re: Help with a weather prediction algorithm based on air ressure and temp
Post by: Josiah on June 20, 2017, 05:01:00 PM
This page may give you a few ideas: https://www.acurite.com/precision-forecasting-white-paper/precision-forecasting-white-paper (https://www.acurite.com/precision-forecasting-white-paper/precision-forecasting-white-paper)
It's a very broad overview of how Acurite did it in their stations. Unfortunately they don't go into specifics.
Title: Re: Help with a weather prediction algorithm based on air ressure and temp
Post by: SLOweather on June 20, 2017, 05:18:40 PM
Google zambretti algorithm. That or a variation of it are what I believe most stations use. There are even a few links to this forum.
Title: Re: Help with a weather prediction algorithm based on air ressure and temp
Post by: Jáchym on June 20, 2017, 06:23:06 PM
Hi,
it is unfortunately a bit more complicated, you would need to also look at not just the tendency but also the actual value and compare it to what is "normal" for the area, then you also need to look at wind speed and then you must also compare the actual tendencies in longer term, i.e. was it going up fast before and now falling rapidly? Is the tendency more or less constant?

A simplified page that might help you
http://www.bohlken.net/airpressure2.htm
Title: Re: Help with a weather prediction algorithm based on air ressure and temp
Post by: vonodna on June 21, 2017, 08:06:09 AM
10x for the quick replies, guys! It seems Zambretti will do the trick. Still have to add RTC and external temperature sensor to my project, but I am confident that it would work. 
Title: Re: Help with a weather prediction algorithm based on air ressure and temp
Post by: vonodna on October 01, 2017, 03:20:51 AM
If someone is interested in what came out of my project here it is:
https://hackaday.io/project/27458-e-ink-weather-station (https://hackaday.io/project/27458-e-ink-weather-station)
Title: Re: Help with a weather prediction algorithm based on air ressure and temp
Post by: mcrossley on October 01, 2017, 06:15:07 AM
I do like those ePaper displays for weather gizmos.