How's the weather?

The weather map includes sea level pressure map and upper air pressure map. People convert the pressures measured at different heights on the earth's surface into sea-level pressures by certain methods, and draw a sea-level pressure map. There are many closed isobars on the map. Generally, the closed circulation center will be marked with H (high pressure) and L (low pressure), and the center pressure will be marked with. Usually, the difference between every two adjacent isobars is 4 hectopascals or 2 hectopascals. The denser the isobar, the greater the pressure gradient force and the greater the wind speed. Then it is judged as low pressure, and the airflow rotates counterclockwise and flows to the center while rotating; For an anticyclone, it rotates clockwise and flows out from the center to judge the wind direction (considering the geostrophic deflection force), which is simply to look at the sea level pressure map.

A very intuitive idea of the high altitude map is that the sea level pressure map corresponds to the pressure distribution at a height of 0m, and the high altitude map only changes the height from 0m to, for example, 5000m. The high altitude wind is parallel to the isobar, rotates counterclockwise along the vortex (equivalent to the low pressure in the sea level pressure map), and rotates clockwise along the high value area (equivalent to the high pressure in the sea level pressure map). The difference between the high altitude contour map and the sea level pressure map is that no component flows out of the high value area and no component flows into the vortex.