COMPUTER MIMICS WEATHER — How and why the world’s weather behaves as it does is being attacked by one of the most powerful computers yet built. The U.S. Weather Bureau in Washington, D.C., dedicated a new research laboratory aimed at gaining better understanding of the earth’s atmosphere. Mathematical models of the atmosphere up to 20 miles above the surface are tested in the new laboratory on an International Business Machines’ STRETCH computer…. The electronic “brain” is expected to simulate day-to-day changes at 10,000 points around the world, analyzing surface weather patterns plus those at nine levels above the surface. Some ten billion computations will be required to model these weather changes during a 24-hour period.