QFF
[At ... (place)] what is the present atmospheric pressure converted to mean sea level in accordance with meteorological practice?
At ... (place) the atmospheric pressure converted to mean sea level in accordance with meteorological practice is (or was determined at ... hours to be) ... millibars.
And, should one wish to confusticate ATC even further; there are more priceles pearls to be found here.
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Must QSY. Toodle Pip!
