Today the barometric pressure in Norway is measured as low as 944 hPa/mbar! This has never happened before.
The regional airline Wideroe have grounded all Dash-8 100/200/300s.
Why? The altimeter will not give correct reading when the pressure is below 948 hPa/mbar, because the lowest setting they can adjust to in these aircrafts is 948.
Standard pressure is 1013 hPa/mbar(2992 hg)
When approaching an airport to land pilots get altimeter setting from ATC e.g. «Altimeter setting 2 9 9 2» So they can adjust the altimeter to the actual pressure and get correct reading from the instrument.
Hopefully we get some pressure soon so the small birds can fly again