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Domain 5. Central America and NW South America
Graphics use 1° GFS Model Output

Terrain elevation in meters above sea level. Source: GFS0.25°(NOMADS-NOAA).

Enhanced GDI and Flow - EGDI.CMD
The Enhanced GDI (EGDI) is an enhanced version of the Galvez-Davison Index (GDI) that adds the detrimental effects of low relative humidity in the 300-400 hPa layer (also proxy for elevated inversions), the detrimental effects of upper convergence, the enhancing/detrimental effects of low-level moisture convergence/divergence, and a precipitable water enhancement factor. As the GDI, it helps to identify environments favorable for shallow convection, deep convection or deep convection with the potential for heavy rainfall. Loops include the low-level (1000-850hPa) and upper level (400-200hPa) flow to account for dynamic and orographic forcing, and movement of systems. It also plots 950-700 hPa convergence/divergence of the flux of mixing ratio, upper divergence (400-200hPa), and GDI advection and flux.
Trade Wind Inversion - TWIN.CMD
Detects the height of the Trade wind inversion's base in shaded colors, and the strength of the inversion using boxes. Larger boxes indicate a stronger inversion.
Tropical/Easterly Wave Tracking - OTRP.CMD
850-600 hPa Mean Flow, 850-500 hPa mean Vorticity and enhanced GDI to track waves in the trades.

Note: These algorithms are only forecast tools, not official forecasts. For information on the algorithms, click on the red text.

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Page last modified: Wednesday, 19-Feb-2020 17:45:33 UTC