Continuous extremely hot weather threatens the safe and reliable operation of distribution networks. Therefore

we propose a risk assessment method for distribution networks under extreme hot weather. Firstly

the spatial and temporal distribution characteristics of the ambient temperature in the distribution area are analyzed

the distribution area is divided into 1 km×1 km grids

and the relationship equation between the regional air temperature of the distribution network and the ambient temperature of each grid is calculated and determined. Secondly

the influence mechanism of extreme hot weather on distribution network is analyzed

and the distribution equipment failure model is established by combining the distribution transformer winding temperature

switchgear ambient temperature and distribution line current carrying capacity

and then the failure probability of power distribution equipment is calculated. Finally

the fault states of distribution equipment are obtained by the Monte Carlo sampling method

and the operational states of distribution network are calculated by considering fault repair and distribution network reconfiguration to realize the assessment of distribution network operation risk. The IEEE-33 node system is configured in an area of Xi'an City as an example

and the results show that the proposed method and indexes can be adopted to reasonably assess the risk of distribution networks under extreme hot weather.