For example, the solid lines on the constant pressure chart below depict the height of the 500 mb surface. So, why use constant pressure instead of “constant altitude” to depict the weather aloft?

Today's question: When we go up to Flagstaff from the Valley, our car tires lose 2-3 pounds of pressure. On the other hand, potato chip bags in Flagstaff all look like they're fully inflated Mylar ...

Manual calibration of the barometer will be done by entering reference values for altitude, sea level pressure, and distance. The weather alarm will activate if the watch detects a pressure drop ...