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Domain 10. Southern Cone / Drake Passage
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. The algorithm is primarily designed for the tropics/subtropics, but it will provide information useful to the southern cone.
Front Analysis - FRONT.CMD
Highlights surface fronts based on horizontal gradients in a field constructed using thickness of 1000-850hPa and 1000-925 hPa; dewpoint at 1000 and 925 hPa; and precipitable water. Plots an average of 1000 and 925 hPa streamlines and wind barbs in kt (gray and black), 1000-850 hPa thickness in GPM (green contours), and the magnitude of the gradient in light blue, yellow and fuscia contours. The 18°C 2m dewpoint contour is included.

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 17:34:21 UTC