blocking high (blocking anticyclone) In synoptic meteorology, an anticyclone with deep circulation so placed as to interrupt or divert the eastward movement of the typical succession of low-pressure features (depressions) in the zonal flow of mid-latitudes. At such times the usual mid-latitude zonal flow is diverted into more meridional flow around the high-pressure area, where settled weather can then result. See also AIR MASS.

blocking high(blocking anticyclone) In synoptic meteorology, an anticyclone with deep circulation so placed as to interrupt or divert the eastward movement of the typical succession of low-pressure features (depressions) in the zonal flow of mid-latitudes. At such times the usual mid-latitude zonal flow is diverted into more meridional flow around the high-pressure area, where settled weather can then result. See also air mass.