Interestingly having just looked at the stations on the Ecowitt and PWS Weather maps I’m amazed by how far adrift many pressure readings are. The Mermaid station is currently reading 1009hPa (adjusted to mean sea level). Manchester airport (about 25km away) is currently reporting QNH of 1010 in their METAR, so the Mermaid seems to be a reasonable value given that the isobars aren’t densely packed today.
Other stations near the Mermaid are reporting as low as 998hPa (not adjusting for altitude?) and 1044hPa (double adjusting for altitude?)
Perhaps no-one cares about atmospheric pressure these days?
I think lots of people just plug them and use them, not realising they must calibrate the pressure reading. They are not the “enthusiasts” we get on the forums.
I’m sure that’s true in some cases, e.g. the 998hPa is likely to be caused by that but I’m not sure how you get to to 1044hPa (34hPa above the correct value) without some fiddling!
One form of fiddling can be that 2 correction-mechanisms are ‘fighting’ each other.
With Weatherflow_Tempest had such case myself:
- initially the pressure-report from the WF-server was significantly off, and locally I compensated in the application using the reading from nearby, official KNMI-station.
- at some time the WF-server ‘saw the light’ and made offset in different direction, requiring me to locally align again.
- since that event vigilant for those reading-differences.
Reason for me to dislike those server-made calibrations …