The Whole Tamale
Using basic physics and powerful computers running systems of equations, it is possible to form a theoretical path for a sounding rocket based on all known parameters, including wind, and even auroral activity.
Currently, The Alaska Student Rocket Project (ASRP) is designing a Sounding Rocket to fly an atmospheric science experiment in March, 2002. Before this rocket is launched, NASAs sounding rocket division (based in Wallops, Va.) will simulate to a fine degree the exact forces acting on the rocket (as best known at the time.) Measurements of wind and atmospheric pressure will be taken. NASA will then recommend a launch angle (Typically 85°.)
The design for the rocket can be found in stages at http://ampere.ee.uaf.edu/~srp4.
Below is a picture of Typical sounding rocket flown by NASA. This rocket (known as SUB-SEM) flew in June, 2000.