Cold drop

A cold drop, also known as a cut-off low (COL), weatherman's woe, a closed low or a cold pool, is defined by the National Weather Service as


A cold drop, also known as a cut-off low (COL), weatherman's woe, a closed low or a cold pool, is defined by the National Weather Service as "a closed upper-level low which has become completely displaced from basic westerly current, and moves independently of that current". Cut-off lows may remain nearly stationary for days, or on occasion may move westward opposite to the prevailing flow aloft. Cut-off lows form in mid-latitudes and would remain nearly stationary for days.
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