An anticyclone is an area of high atmospheric pressure which causes settled weather conditions and, in summer, clear skies and high temperatures.
anticyclone in British English
(ˌæntɪˈsaɪkləʊn)
noun
meteorology
a body of moving air of higher pressure than the surrounding air, in which the pressure decreases away from the centre. Winds circulate around the centre in a clockwise direction in the N hemisphere and anticlockwise in the S hemisphere
a system of rotating winds over a vast area spinning out from a high pressure center (clockwise in the Northern Hemisphere) and generally causing fair weather: commonly called a high since it coexists with high barometric pressure