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7.5 MD files - Meteorological Diagrams

In this exercise, you will create four types of meteorological diagrams: a Skew-T diagram, a hodograph, a vertical cross section and a surface meteorogram. You will also list surface data in a tabular format.

  1. Erase the images and graphics in frames 1 through 6.

    Type: ERASE F 1 6

  2. List the upper-air reporting stations in position 2 of the MYDATA/TEST-PTSRCS dataset that you copied in the previous exercise.

    Type: PTLIST MYDATA/TEST-PTSRCS.2 PAR=IDN NUM=ALL

  3. Choose one of the stations listed. Show frame 1 and plot a Skew-T diagram for your chosen station (in this case, 72304, which is Cape Hatteras, North Carolina) at 12 UTC using the data in MYDATA/TEST-PTSRCS.2.

    Type: SF 1;UAPLOT 72304 12 93072 DATASET=MYDATA/TEST-PTSRCS.2

  4. Plot a hodograph of the data from Cape Hatteras on frame 2. Show frame 2

    Type: HODO 72304 12 93072 GRA=2 DATASET=MYDATA/TEST-PTSRCS.2;SF 2

  5. Show frame 3 and display a map of the stations contained in this dataset.

    Type: SF 3;PTDISP MYDATA/TEST-PTSRCS.2 PARAM=IDN MAP=USA

  6. Choose two stations that are the farthest apart on the map. Show frame 4 and display a vertical cross section of theta, wind, and mixing ratio values from these two stations (in this case, Waycross, Georgia (72213) to Washington/Dulles, Virginia (72402)) using upper air data from MD file 4001. The MAP=YES keyword displays a map in the upper-right corner showing the cross section location and stations selected.

    Type: UACROSS 72213 72402 MAP=YES DATASET=MYDATA/TEST-PTSRCS.2 TIME=12 DAY=13/MAR/93 PARAM=THA WINDB MIX GRA=4;SF 4

  7. Show frame 5 and plot a 24-hour surface meteorogram for Macon, Georgia, ending at 23 UTC on 13 March 1993 using data from the BLIZZARD/SFCHOURLY dataset.

    Type: SF 5;SFCMG MCN TIME=23 DAY=13/MAR/93 DATASET=BLIZZARD/SFCHOURLY

  8. List the surface hourly data for Macon, Georgia for the past 24 hours.

    Type: SFCLIST MCN TIME=0 23 DAY=13/MAR/93 DATASET=BLIZZARD/SFCHOURLY

    You should notice that the data listed in the Text Window is the same as that displayed in the Image Window.

  9. Exit McIDAS.

    Type: EXIT


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