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California Regional Weather Server
Instructions for Animations of Jet Stream Forecasts

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The WWWeb server (virga.sfsu.edu) receives GFS model forecast output data to construct a new jet stream analysis every 6 hours, within 5 hours after the map analysis time. The map analysis times, the starting times for forecasts, are 00Z, 06Z, 12Z, and 18Z.

Starting Instructions:

• Click on the "Build Animation" button to load images and start the animation.

• Speeding up the animation: Up do a point, each time that you click on the "Faster" button you will reduce by 0.1 seconds the time that the animation lingers on each image, which speeds up the animation.
  
  
• Slowing down the animation: Conversely, each time that you click on the "Slower" button you will increase by 0.1 seconds the time that the animation lingers on each image, which slows down the animation.
  
  
• Stepping through the animation frame by frame: To step through animations frame-by-frame, first press the "Pause" button (), then press the "Next" button (") repeatedly to advance frames one at a time. Similarly, press the "Prev" button () to step backward one frame at a time.
  
  
• Resumeing a paused animation: To restart the animation after pausing it, press the "Resume" button ().
  
  

Trouble-shooting:

• If the animation does not seem to be working correctly, check your computer's date/time--the animation depends on its accuracy!

• In your browser's Preferences, make sure that JavaScript (or simpley "scripting" is enabled. (Under Netscape's Preferences, this is probably set in the "Advanced" category. In Microsoft's Internet Explorer, try looking in the "Web Browser" section of Preferences, under "Web Content" or "Advanced".)
• If you resize the browser window you might need to press the browser's Reload button or choose Reload from the View menu.

WWWeb Site Navigation: