NUMERICAL MODEL
A 3-D nonhydrostatic numerical model is being used to forecast the position, strength and depth of convergence lines, as well as the moisture convergence (Crook and Tuttle, 1994-ref). The model is initialized by interpolating wind observations (derived from Doppler radar (using TREC), surface mesonet and upper air sounding data) to the model grid. A thermodynamic retrieval is used to calculate the buoyancy in the boundary layer.
Gridded model fields of the predicted convergence line location, strength and depth, moisture convergence and stability (primarily CAPE and CIN) will soon be incorporated into the auto-nowcast algorithm. These fields will provide crucial information about the boundary layer convergence characteristics.
Example of model forecasted convergence line:
For more information on the numerical model go to Crook's numerical model page
Go to Cu cloud detection algorithm
Go to Auto-nowcasting algorithm
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