What is the red high temperature warning?

The red warning of high temperature is that the maximum temperature rises above 40℃ within 24 hours.

High temperature red warning signal is an early warning signal made by meteorological departments through meteorological monitoring before the arrival of high temperature, reminding people to take precautions, minimizing the discomfort caused by high temperature and avoiding the occurrence of heatstroke. High temperature red warning signal is the third level (the highest level) of high temperature warning signal.

In the high temperature environment, the human body should maintain the balance of body temperature through evaporation and heat dissipation.

"In the process of evaporation (sweating), salt is lost with sweat, blood concentration, hemoglobin and red blood cells increase, blood viscosity increases, and the burden on the heart and blood vessels increases, thus causing blood pressure to drop. In order to maintain normal blood pressure, the burden on the heart is heavier. Because the skin sweats a lot, the water discharged by the kidneys is reduced, which also affects the renal function.