Mesonet

In meteorology (and climatology), a mesonet, portmanteau of mesoscale network, is a network of (typically) automated weather and environmental monitoring stations designed to observe mesoscale meteorological phenomena.Dry lines, squall lines, and sea breezes are examples of phenomena that can be observed by mesonets. Due to the space and time scales associated with mesoscale phenomena, weather stations comprising a mesonet will be spaced closer together and report more frequently than synoptic scale observing networks, such as ASOS. The term mesonet refers to the collective group of these weather stations, and are typically owned and operated by a common entity. Mesonets usually record in situ surface weather observations but some involve other observation platforms, particularly vertical profiles of the planetary boundary layer (PBL).

The distinguishing features that classify a network of weather stations as a mesonet are station density and temporal resolution. Depending upon the phenomena meant to be observed, mesonet stations utilize a spatial spacing of 1 to 40 kilometres (0.62 to 24.85 mi) and report conditions every 1 to 15 minutes. Micronets (see microscale and storm scale), such as in metropolitan areas such as Oklahoma City,St. Louis, and Birmingham UK, may be even denser in spatial resolution.

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