calculate the trend of barometric p how to calculate barometric trend how do you determine barometric pressure trend what is the trend of barometric pressure how to determine barometric trends how to calculate barometric pressure trend how do you calculate barometric pressure? how to predict the trend in barometric pressure how is barometric pressure trended barometric pressure trend what is the trend of barometric how do you calculate barometric pressure trends? what is barometric how to determine a trend of barometric pressure what is the trend of barometric pressure when barometric pressure rises what happens how do i know if pressure is rising or falling how do you calculate barometric pressure how do i determine the trend for barometric pressure what is trending barometric pressure