Chilled Air Column (65 F)
Heated Air Column (88 F)
Chilled Air Column (65 F)

Upper Level LOW

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Strengthening Upper Level HIGH (divergence)

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Upper Level LOW

36000 feet

Subsidence

Upward Motion

Subsidence

18000 feet

THERMAL HIGH

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THERMAL (warm core) LOW (convergence)

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THERMAL HIGH

Surface
Warmed Air Colum