calculating height falls


Greetings....

Sorry if this is an easy one, but I am new to this and have not been able to find info on the gembud email archive. I would like to plot the
500mb height falls (as was standard on the old DIFAX maps).  Is there a
way to do this with the observed data, or am I better off using the
initialization fields from the NAM or GFS?
Thanks in advance...

peace,
frank

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Frank J. Marsik
U-M Air Quality Laboratory            "We must remember that intelligence
Space Research Building, Rm 2109       is not enough.  Intelligence  -
2455 Hayward Ave                       plus character - that is the goal
Ann Arbor, MI  48109-2143              of true education."

Phone: 734-763-5369                             - Martin Luther King
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URL: http://www.umich.edu/~marsik/

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