As Hurricane Joaquin rumbles on in the central Bahamas, it has been downgraded from a category 4 to a category 3 hurricane with 125 mile per hour winds. NASA is keeping a close eye on the hurricane with the Global Precipitation Measurement Mission.
Tonight on “This Week,” NASA scientist Dr. George Huffman tells us about that mission. Here’s the transcript of our conversation:
Joey: Tell me what you’re able to see in the 3D view of Hurricane Joaquin.
Dr. Huffman: Well, the Global Precipitation Management System, or GPM, has a core observatory with two advanced instruments one of which is a radar which allows you to look down through the layers of the storm, like a cat scan. The reds are heavy rain and the blues are snow. This was taken at a time where it still was a tropical storm and you see an anvil of snow being blown off near the center of the storm indicating the unfavorable winds that were preventing development. Shortly after this, the winds subsided and the storm started developing quickly.
Joey: What’s causing the hurricane to keep it’s intensity.
Dr. Huffman: Well, over its entire lifetime Joaquin has been over very warm waters which is favorable to development. In the beginning there was environmental wind which was unfavorable. Different winds at different levels that were causing that snow to blow off. Once those winds subsided it allowed the storm to develop relatively rapidly and give us the typical donut precipitation around the center of the storm which are characteristic of heavy rain and a very strong storm.
Joey: Even though it’s moving away from land what can we expect from this storm?
Dr. Huffman: Once the storm started moving to the North, according to forecasts, it will most likely stay away from land, but there are actually two things that are going to happen. First is that the storm itself will gradually decay, but meanwhile on the east coast of the United States it turns out that we have a completely separate system, which is feeding off the same tropical moisture. This frontal band is forecast to give us large amounts of rain. What we can do with GPM is track the development of that accumulation. We’ve already done that with the first part of the storm. At the same time you can visualize both the rainfall over the east coast as well as the rainfall that’s happening with Joaquin. We can accumulate these observations in real time and hand them off to the emergency managers and the forecasters for their use in determining what the risk is in their area.
Joey: Ok, and for us weather nerds where can we learn more about this 3D system.
Dr. Huffman: For everybody you can go to our website at nasa.gov/gpm and follow us on twitter @nasa_rain.
Joey: Dr. George Huffman, thank you for joining us.
Dr. Huffman: Thank you.