Synoptic Scale
Synoptic scale refers to weather phenomena that can be depicted on a standard weather map — systems spanning thousands of kilometres, such as high and low pressure systems, fronts, and major air mass boundaries. Synoptic-scale weather is what drives the “big picture” of aviation weather across a continent.
Scale of Weather Systems
- Synoptic scale (meso-α to synoptic): 1,000–10,000 km; fronts, cyclones, anticyclones; multiple-day evolution; GFA and synoptic charts
- Mesoscale: 10–1,000 km; squall lines, sea breezes, mountain waves; hours to days; harder to forecast precisely
- Microscale: < 10 km; gusts, thermals, turbulence eddies; minutes; essentially unpredictable in advance
Synoptic Weather Analysis
Pilots use synoptic-scale analysis to understand the overall weather pattern driving their flight. The surface analysis chart shows fronts, isobars, and high/low centres. The upper air analysis shows the jet stream position and significant troughs and ridges. Together, these tools allow pilots to anticipate the types of weather they will encounter.
Related Terms
See also: Cold Front, Warm Front, Jet Stream, Trough.