How do I measure barometric pressure outdoors?

The Vaisala Static Pressure Head (SPH) accessory is recommended for outdoor installation. Wind induced effects are one of the main sources of error when measuring barometric pressure. Variations due to strong and gusty winds can be overcome by using a static pressure head to ‘filter out’ the effect of dynamic pressure. The Vaisala Static Pressure Head Series SPH10/20 is designed to minimize errors caused by wind. This wind-tunnel-tested structure is both horizontally and vertically symmetrical to ensure reliable barometric pressure measurements in all weather conditions.

The barometer should be installed above the SPH so that any condensed water in the connecting tube can flow out through the SPH and will not penetrate the Vaisala BAROCAP^® sensor. Care should be taken when positioning the tubing to avoid water traps.