The main characteristics of the general atmospheric circulation in October 2018 are as follows. Over the Northern Hemisphere, the polar vortex showed a dipole pattern. The circulation presented a fourwave pattern in middlehigh latitudes. The western Pacific subtropical high extented remarkably more westward than normal. The monthly mean precipitation amount was 28.1 mm, which is 21.6% less than normal (35.8 mm). The monthly mean temperature was 9.9℃, 0.4℃ lower than normal (10.3℃), ranking the lowest since 2002. There was no largerange heavy rainfall processes over China. There were five cold air processes, more than usual, and two fog and haze events in the region of BeijingTianjinHebei, which were also weaker than usual. There was no landfall typhoon in October 2018.