My air pressure (station pressure and sea level pressure) shown on my WeatherFlow station is too high. All my surrounding WeatherFlow Stations and my own VantagePro 2 weather station show values about 4.5 hPa lower than measured by the WeatherFlow station. Is there a possibility to correct this value?
Greetings from Basel, Switzerland
Thomas
two questions. if you go to the app, setup, station, What is your elevation? (for basel it should be something around 279 m.
if you go from there to manage devices, air unit, What is the height above ground? (depending on your setup it should be probably something less then 5m, unless you live on the 10th floor in some apartment building)
My altitude is around 265 m. My VantagePro and the WeatherFlow station are on the same height and should therefore show more or less the same station pressure.
and what did you fill in at height above ground?
(basically that will be added to your altitude to determine the height above sealevel, which is needed to calculate the sealevel pressure)
I just checked the WeatherFlow app. Station height is there at 260 m.
There are two height settings.
One is elevation which is the height of the ground above sea level.
The second is height above ground level of the device.
It is important that you have both of these set accurately.
Height above ground level is set to 1 m
That’s really low for the Sky to be mounted.
Is your sky mounted that hight ?
What are the value of accuracy and repeatability of the different sensors ?
It’s the Air which is 1 m above ground level. As far as I know is Air measuring air pressure and temperature. Standard should be 2 m above grassy ground. Sky is on the roof.
Duh. That is correct. I have no idea why I thought Sky
Sensor values seem to be OK; no jumps etc. The difference between WeatherFlow and Davis is more or less constant.
260 m for stationheight above sea-level and air height of 1 m seems perfectly acceptable values for your location. And doesn’t explain the difference you see with other nearby stations (but note that you can only compare the sea level values ( asuming they are setup correctly). 4 hPa is about 40 m difference. So even if your station height is a few meter off, it wouldn’t explain the difference
Make sure you understand that the Davis Vantage Pro’s barometer sensor is located inside the console unit and not inside the hygrometer on the station. Due to elevation difference of your AIR and Vantage Pro console, the pressure observations may differ. Your Vantage Pro’s barometer sensor should be calibrated to your nearest METAR station (local airport station) as recommended by NWS. It is also a requirement for being a MADIS station as part of CWOP.
I know. The difference in height between the Vantage console and the Air ist about 2 m.
It looks like your pressure sensor is a bit out of calibration. We are close to launching the pressure component of our continuous learning system, which will automatically apply a correction to units that need it. Please be sure your elevation and height above ground are set correctly and give us a bit of time to roll this component out. Thanks!
Hello, I have the same problem. Mine is consistently close to 3mb too high. I was told that the unit would self adjust using some AI calibration but this hasn’t happened. I have a government survey marker nearby so the programmed elevation is reasonably accurate, well within 1mb accuracy. Initially I adjusted the program elevation to adjust the atmospheric pressure but I was told to set it to the correct elevation and await calibration.
If you read the messages from WeatherFliw and David, you will learn that it is being worked and has not been turned for all stations.
Thanks Gary, that would have been a good response a couple of months ago rather than telling me to wait and it would shortly sort itself out. I keep a close eye on the QNH as I’m a pilot and fly from my property. The weather station is to provide me with conditions at my runway so I’m looking forward to being able to rely on it and not have to add 2.7mb. I don’t usually frequent the forum. Only check it when the summary email comes through.
WeatherFlow is constantly checking stations and gathering data. This is a huge effort to analyze and build the capabilities to calibrate each station.
Without very precise and expensive equipment at every site it’s still going to be a best effort. I have been discussing accuracy with techs at KAPA and it’s a constant battle to keep the equipment calibrated and accurate. And that’s at the high end. This consumer product is a bigger.