This illustration shows how cooler than normal tropical Pacific Ocean temperatures (blues) and warmer than normal tropical Atlantic Ocean temperatures (red and orange) contributed to a weakened low level jet stream and changed its course. The jet stream normally flows westward over the Gulf of Mexico and then turns northward pulling up moisture and dumping rain onto the Great Plains. During the 1930s, this low level jet stream weakened, carrying less moisture, and shifted further south. The Great Plains land dried up and dust storms blew across the U.S. Note: This is the standard definition version Dust Bowl Climate Conceptual animaiton MPEG. Animator: Susan Twardy (HTSI). Scientist: Siegfried D. Schubert (NASA/GSFC). Writer: Rani Chohan (NASA/GSFC).