A method and structure which provide an ambient pressure measurement that is unaffected by wind and localized environmental conditions. A draft range pressure transmitter is enclosed inside an enclosure which is resistant to wind and other transient localize environmental conditions. A vent cap allows slow air movement through a wall of the enclosure and forms a still air chamber for the transmitter. The pressure inside the enclosure changes at the same rate as the barometric pressure but is unaffected by wind or wind gusts.