From a Met point of view [and I ceased being involved in 1997 so may be behind the curve]
The barometric pressure is to be read "frequently" when pressure is changing rapidly, and a "Special on QFE" issued to ATC against a signature or initials.
This was done scrupulously on RAF stations, with highly skilled and well-motivated observers who were often on watch solo. It was mandatory to keep a running log of pressure [hourly or half-hourly] and the observer was expected [of course] to be conversant with the overall Met. situation. We regarded monitoring of pressure as Holy writ, drummed into us on Day One..