The weather forecast shows 500 hectopascals.

The standard air pressure is 10 1325 Pa (i.e. 1 0/3.25 hectopascals,10/3.25 mbar,1atmospheric pressure). If it is lower than this value, then this area is a low pressure area. If it is higher than this value, it is a low pressure area.

The 500 hectopascals mentioned in the weather forecast mean that this area is a low pressure area.

In weather forecast, many different units are used to measure air pressure, and the international standard unit of measurement is Pa. For example, the China Meteorological Service Center is used to measure the barometric pressure of hectopascals, and the US Meteorological Service Center is used to measure the barometric pressure of millibars.