SURVEY OF METEOROLOGY II LAB #10

Introduction to Upper Air Analysis

Lab Objectives:

• To learn the basic skills of analyzing and interpreting upper air maps.

ASSIGNMENT:

1. 850 mb - Print out an 850mb difax map valid at 12 Z today over North America.

   • On this map, calculate the dew point temperature from the temperature and dew point depression.  Then, analyze isodrosotherms, beginning at 6 degrees C with an interval of 3 degrees C. 

   • Highlight the 0 degree C line (rain/snow line)

   • Highlight the -10 degree C line (leading edge of arctic air).

2. 500 mb - Print out the 500 mb difax map valid at 12 Z today over North America.

   • Contour the 12 hr height falls (italic numbers to the lower right of station model).  Contour only the negative height falls beginning with the -03 decameters (30m) and an interval of 30 m.

   • Sketch the surface frontal positions on the 500 mb chart to better see the relationship between the surface and upper-level features.  The surface fronts can be retrieved from the surface analysis difax map valid at 12Z.

3. 250 mb - Print out the 250 mb difax map valid at 12Z today over North America.

   • Trace out the 50 knot isotach.  Using the isotachs and satellite data, indicate the positions of the polar and sub tropical jets on this chart.  Label all jets that you see.

last updated: 11/16/04 04:51 PM