Pressure not updating

[Arnie]

Brilliant Steve
Ive set the offset to +3.00 and restarted Cumulus
It has started up with a 1034.1 reading straight away

Thanks again Steve

[GraemeT]

Brian,
Here's a calculator you can use to get the correct relative pressure setting for your station.
You enter your altitude and the abs. reading from the weather station and it will calculate the rel. pressure setting for you.
Once set, you shouldn't need to use an offset in Cumulus.

http://www.srh.noaa.gov/epz/?n=wxcalc_altimetersetting

Cheers,

[steve]

Once set, you shouldn't need to use an offset in Cumulus.

I don't think Brian is using an offset in Cumulus, I think he is (correctly) setting it in the station.

http://www.srh.noaa.gov/epz/?n=wxcalc_stationpressure

That's fine for theoretical purposes, but it's better to set your station so that its relative/sea-level pressure reading agrees with a nearby reliable reference, whatever offset that happens to give.

[Super-T]

Calculator doesn't work for me.
I am at 46 Metres according to Google but I would have to tell the calculator that I am at 100 metres to get the corrected Relative pressure compared to Airport readings.
Maybe the great Google is wrong

[Arnie]

Once set, you shouldn't need to use an offset in Cumulus.

I don't think Brian is using an offset in Cumulus, I think he is (correctly) setting it in the station.

Quite correct Steve

http://www.srh.noaa.gov/epz/?n=wxcalc_stationpressureThat's fine for theoretical purposes, but it's better to set your station so that its relative/sea-level pressure reading agrees with a nearby reliable reference, whatever offset that happens to give.

Graeme
Isnt that the difficulty, My closest BOM station (Bankstown Airport) is 10Klms away and an altitude 20m lower than mine. At 1500 today Bankstown was showing 1027hpa (rounded) and mine was 1026.8hpa
With nearby PWS's there is no guarantee of accuracy.
How accurate can we get?

[steve]

My closest BOM station (Bankstown Airport) is 10Klms away and an altitude 20m lower than mine.

10km away is fine, and the altitude difference doesn't matter as the pressures are corrected for that anyway. Choose a day with a good stable high pressure, and set your station to the same as the BOM station.

[GraemeT]

Terry,
I'm not sure if GoogleEarth is as precise as we'd like.
Google says I'm at 113m and the GPS says 120m...
I used the GPS altitude.