These guys may know about meteors, but they don’t know a damn about the weather. It’s raining, but it’s evaporating before it hits the ground. Then it’s not raining dickweed!!!
They are using the GEOPOT height for forcasts.
500 hPa (GPDM) and MSLP Geopotential height which the US National Weather Service defines as: roughly the height above sea level of a pressure level. For example, if a station reports that the 500mb height at its location is 5600m, it means that the level of the atmosphere over that station at which the atmospheric pressure is 500mb is 5600 meters above sea level. This is an estimated height based on temperature and pressure data. Mean Surface Level Pressure (MSLP) is usually shown on the 500hPa GPDM plots with contours. The 500hPa plots are useful for a range of reasons, one being that computer models usually forecast this level better than surface conditions at longer ranges.
