cold low

views updated May 21 2018

cold low Basically, a non-frontal depression that is typically associated with circulation in cold air masses in the mid-troposphere over the north-eastern USA and north-eastern Siberia, though it sometimes also occurs over the oceans in air that has emerged from the Arctic. Cold lows, marked by more or less concentric isotherms around the core of the low, may originate along the Arctic coast as a result of strong vertical uplift and adiabatic cooling in occlusions. They do not necessarily influence surface weather conditions, but when they occur over warmer surfaces in middle latitudes, convection develops strongly. See also cut-off low.

cold low

views updated May 08 2018

cold low Basically non-frontal depression, typically associated with circulation in cold air masses in the mid-troposphere over north-eastern USA and north-eastern Siberia, though sometimes occurring also over the oceans in air that has emerged from the arctic. Such depressions are marked by more or less concentric isotherms around the core of the low. Such lows may originate along the arctic coast as a result of strong vertical uplift and adiabatic cooling in occlusions; they do not necessarily influence surface weather conditions, but when they occur over warmer surfaces in middle latitudes, convection develops strongly. See also CUT-OFF LOW.