Southern Oscillations - An oscillation in surface pressure differences between Tahiti and Darwin, Australia. This oscillation has a period of a few years. The unbroken line of thunderstorms or squalls extending over several hundred miles in length which often forms over or ahead of fast-moving cold fronts at mid latitudes. These squall lines often produce strong straight-line winds and hail near their leading convection edge. A trailing stratiform precipitation region is found behind the leading edge.
Unstable models are definitely inaccurate.
Stable models may or may not be accurate. Such a nucleus has a stable configuration of protons and neutrons. Standard Atmosphere - Hypothetical vertical profile of the atmosphere that was developed to represent the time and horizontally averaged distribution of temperature, pressure, and density. In the standard atmosphere, pressure, density and temperature are a function of height only. The standard atmosphere is used internationally to standardize calibrations and measurements.