Regional And Mesoscale Meteorology Team
Daily Satellite Discussion
Wednesday November 5, 1997
With the capability that McIDAS has, of converting MD files into grid fields, one is able to display such parameters as streamlines, speed divergence, and isotachs. In the top left image of the four attached images, the green wind barbs represent winds in the 300 to 400 mb range of the atmosphere, as calculated automatically by NESDIS from water vapor imagery. The water vapor image from the valid time is shown at the upper right.
The yellow streamlines on the bottom left represent streamlines of the winds, in the 300 to 400 mb layer of the atmosphere . This particular grid field was created by using the McIDAS commands MDX and IGG MAKE which convert the MD file data into individual U and V grid fields, and then plotting the desired derived grid field. The last plot represents speed divergence at the surface, using a NESDIS cloud drift wind set derived from visible data. This is more representative of winds at the surface and was created from gridded data as well.
Gridded data sets can be created from any kind of MD file. See your Mcidas help manual and in particular, commands IGU, IGG, MDX, GRDDISP. For more information on the NESDIS high density wind data sets go to the NOAA web page.