Nav: Home

NASA sees heavy rain in Gaston as it fights wind shear

August 25, 2016

Gaston was a hurricane when the Global Precipitation Measurement mission or GPM core satellite passed overhead and found heavy rain occurring in the storm. GPM imagery also showed that wind shear was stretching the storm out and making it appear elongated from space.

Gaston became the 3rd hurricane of the season early this morning, Aug. 25 (just after midnight EDT) as the storm was moving northwestward into the Central Atlantic about midway between the Leeward Islands and the Cape Verde Islands before weakening back into a tropical storm less than 12 hours later.

Gaston is continuing to battle relatively strong environmental wind shear brought about by an upper-level low pressure center positioned to the west of Gaston. Winds flowing counter-clockwise around the upper low are blowing from the southwest while Gaston is moving northwest. These opposing winds are causing Gaston to become tilted and make it difficult for the storm to consolidate the energy being released through condensation in embedded thunderstorm updrafts.

GPM captured an image of Gaston early this morning at 1:46 a.m. EDT (5:46 UTC) soon after the storm became a hurricane. When GPM passed over the storm, the National Hurricane Center (NHC) reported that Gaston had maximum sustained winds of 75 mph, making it a minimal hurricane. GPM is a joint mission between NASA and the Japanese space agency JAXA.

At NASA's Goddard Space Flight Center in Greenbelt, Maryland, rain rates derived from the GPM GMI (over the outer part of the storm) and DPR (the inner part of the storm) were overlaid on enhanced infrared data from NOAA's GOES-East satellite to show the location of the heaviest rainfall within the entire storm. The composite image showed Gaston was not circular, but very asymmetric. Heavy rain with rates of around 50 millimeters per hour (~2 inches/hr) were occurring near the center and most of the rain was located north and east of the low-level center of circulation, which reflects the effects of the southwesterly wind shear noted by NHC. These two opposing forces will determine Gaston's intensity over the coming days.

At 11 a.m. EDT (1500 UTC), the center of Tropical Storm Gaston was located near latitude 20.4 North, longitude 44.4 West. Gaston is moving toward the northwest near 17 mph (28 kph), and this general motion is expected to continue through Friday, Aug. 26. A turn toward the west-northwest and a decrease in forward speed are expected on Saturday, Aug. 27.

Maximum sustained winds have decreased to near 70 mph (110 kph) with higher gusts, and some additional weakening is possible today. The estimated minimum central pressure is 992 millibars.

Initially, Gaston should continue to feel the adverse effects of the wind shear; however, NHC is forecasting the shear to weaken after a day or so and for Gaston to become a hurricane once again as it moves over increasingly warmer waters.

Gaston is expected to continue moving generally to the northwest over the next several days but remain east of Bermuda before turning back to the northeast.
-end-


NASA/Goddard Space Flight Center

Related Hurricane Articles:

2017 hurricane season follows year of extremes
2016 hurricane season started in January and ended 318 days later in late-November.
Study Offers New Insight on Hurricane Intensification
In a new study, researchers from the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science showed the first direct observations of hurricane winds warming the ocean surface beneath them due to the interactions with currents from an underlying warm-water whirlpool.
NASA provides a 3-D look at Hurricane Seymour
Hurricane Seymour became a major hurricane on Oct. 25 as the Global Precipitation Measurement mission or GPM core satellite analyzed the storm's very heavy rainfall and provided a 3-D image of the storm's structure.
NASA sees Hurricane Seymour becoming a major hurricane
Hurricane Seymour was strengthening into a major hurricane in the Eastern Pacific Ocean when the NASA-NOAA Suomi NPP satellite passed over it from space.
NASA animation shows Seymour becomes a hurricane
Tropical Depression 20 formed in the Eastern Pacific Ocean on Sunday and by Monday at 11 a.m. it exploded into a hurricane named Seymour.
Hermine becomes a hurricane in the Gulf of Mexico
Tropical Storm Hermine officially reached hurricane status on Thursday, Sept.
NASA spies major Hurricane Georgette
Hurricane Georgette is a major hurricane in the Eastern Pacific Ocean.
NASA peers into major Hurricane Blas
As NASA satellites gather data on the first major hurricane of the Eastern Pacific Ocean hurricane season, Blas continues to hold onto its Category 3 status on the Saffir Simpson Wind Scale.
NASA gets an eyeful of Hurricane Blas
Satellites eyeing powerful Hurricane Blas in the Eastern Pacific Ocean revealed a large eye as the powerful storm continued to move over open waters.
Early use of 'hurricane hunter' data improves hurricane intensity predictions
Data collected via airplane when a hurricane is developing can improve hurricane intensity predictions by up to 15 percent, according to Penn State researchers who have been working with the National Oceanic and Atmospheric Administration and the National Hurricane Center to put the new technique into practice.

Related Hurricane Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Digital Manipulation
Technology has reshaped our lives in amazing ways. But at what cost? This hour, TED speakers reveal how what we see, read, believe — even how we vote — can be manipulated by the technology we use. Guests include journalist Carole Cadwalladr, consumer advocate Finn Myrstad, writer and marketing professor Scott Galloway, behavioral designer Nir Eyal, and computer graphics researcher Doug Roble.
Now Playing: Science for the People

#529 Do You Really Want to Find Out Who's Your Daddy?
At least some of you by now have probably spit into a tube and mailed it off to find out who your closest relatives are, where you might be from, and what terrible diseases might await you. But what exactly did you find out? And what did you give away? In this live panel at Awesome Con we bring in science writer Tina Saey to talk about all her DNA testing, and bioethicist Debra Mathews, to determine whether Tina should have done it at all. Related links: What FamilyTreeDNA sharing genetic data with police means for you Crime solvers embraced...