A
wake low, or
wake depression, is a
mesoscale low-pressure area which trails the mesoscale high following a
squall line. Due to the subsiding warm air associated with the systems formation, clearing skies are associated with the wake low. Once difficult to detect in
surface weather observations due to their broad spacing, the formation of mesoscale
weather station networks, or
mesonets, has increased their detection.
Severe weather, in the form of high
winds, can be generated by the wake low when the pressure difference between the mesohigh preceding it and the wake low is intense enough. When the squall line is in the process of decay,
heat bursts can be generated near the wake low. Once new
thunderstorm activity along the squall line ends, the wake low associated with it weakens in
tandem.