'Mesoscale Meteorology' is the study of
weather systems smaller than
synoptic scale systems but larger than
microscale and
storm-scale cumulus systems. Horizontal dimensions generally range from around 5
miles to several hundred miles. Examples of mesoscale weather systems are
sea breezes,
squall lines, and
mesoscale convective complexes.
Vertical velocity often equals or exceeds horizontal velocities in mesoscale meteorological systems due to nonhydrostatic processes.
Subclasses
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]
See also
★
Scale (spatial)
★
Surface weather analysis
References
World Wide Web
1. David Roth. Hydrometeorological Prediction Center. Unified Surface Analysis Manual. Retrieved on 2006-10-24.
Books and Publications
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]
External links
★ http://meted.ucar.edu/mesoprim/mesodefn/print.htm