Mesoscale Meteorology is divided into these subclasses (Orlanski, 1975):
Meso-gamma 2-20 km, deals with phenomena like thunderstorm convection, complex terrain flows (at the edge to microscale, also known as storm-scale)
Meso-beta 20-200 km deals with phenomena like sea breezes, lake effect snow storms
Meso-alpha 200-2000 km fronts, deals with phenomena like squall lines, mesoscale convective systems (MCS), tropical cyclones at the edge of synoptic scale
Mesoscale boundaries
As in synoptic frontal analysis, literature about mesoscale analysis uses cold, warm, and occluded fronts on the mesoscale to help describe phenomena. On weather maps mesoscale fronts are depicted as smaller and with twice as many bumps or spikes as the synoptic variety. In the United States, opposition to the use of the mesoscale versions of fronts on weather analyses, has led to the use of an overarching symbol (a trough symbol) with a label of outflow boundary as the frontal notation.[1]
Orlanski, I., 1975: A rational subdivision of scales for atmospheric processes. Bulletin of the American Meteorological Society, 56(5), 527-530.
Fujita, T. T., 1986. Mesoscale classifications: their history and their application to forecasting, in Ray, P. S., ed., Mesoscale Meteorology and Forecasting: American Meteorological Society, Boston, p. 18-35. [presented 1984; published 1986]