The University of Wisconsin is one of the best sources for awesome weather images on the internet, and one of the gems on their website shows animated loops of water vapor flowing across the world's oceans. They're absolutely mesmerizing to watch.
(Note — all images in this post are animated. They may take a few moments to load.)
The images created by the Cooperative Institute for Meteorological Satellite Studies, or CIMSS, show the "total precipitable water" in the atmosphere. Precipitable water (sometimes shortened to PWAT) is the amount of rain that would fall if all of the water vapor in the atmosphere were to condense and fall as rain. Higher precipitable water values equates to higher levels of moisture in the atmosphere. On these images, warmer colors equal higher values.
The image at the top of this post is a global analysis created for this past Sunday and Monday. You can see the constant flow of moisture in the tropics on either side of the equator, with the occasional burst of moisture towards the poles when a low pressure system wraps in moisture.
Here's the animation showing Super Typhoon Haiyan striking the Philippines and Vietnam back in November 2013. Haiyan packed winds of 195 MPH at its strongest point, and killed over 6,000 people when it struck the Philippines.
Here's Hurricane Sandy as it traversed the western Atlantic before crashing into the New Jersey coast in late October 2012.
2011's Hurricane Ophelia is a pretty interesting case on these animations. A cold front sweeping away from the east coast of the United States served as a barrier to keep the Category 4 storm away from the country, sending it careening into Newfoundland and Labrador instead.
[Images via CIMSS]