TRMM satellite sees Melissa's tropical transition

Nov 20, 2013
NASA's TRMM satellite saw Melissa on Nov. 20 after it became tropical. The tallest thunderstorms, over 8 miles high, were located northwest of the center. Credit: SSAI/NASA, Hal Pierce

Once a subtropical storm, now a tropical storm, Melissa made the transition on Nov. 20 as NASA's TRMM satellite passed overhead and measured rainfall rates within the storm.

NASA's Tropical Rainfall Measuring Mission or TRMM satellite passed directly above newly transformed Tropical Storm Melissa's center of circulation on November 20, 2013 at 11:21 UTC/6:21 a.m. EST. TRMM's Precipitation Radar (PR) instrument found that rain was falling at a maximum rate of 55 mm/~2.2 inches per hour in an area just to the southeast of Melissa's center of circulation.

TRMM Precipitation Radar data were also used to create a 3-D image that showed Melissa's structure. The TRMM data revealed that the tallest towers, reaching heights of over 13km/~8 miles, were located in a band of rainfall to the northwest of Melissa's center. The strongest intensity radar echo of over 49dBZ was returned from an area of heavy convective storms near Melissa's center. This heavy convection near the center signaled Melissa's transition from a to a tropical storm.

At 1500 UTC/10 a.m. EST, Melissa's maximum sustained winds were near 60 mph/95 kph. Melissa is a good sized storm, as tropical storm force winds extend outward up to 205 miles/335 km from the center.

The MODIS instrument aboard NASA's Aqua satellite captured this image on Nov. 19 at 16:30 UTC/11:30 a.m. EDT of Subtropical Storm Melissa in the North Atlantic Ocean. Credit: NASA Goddard MODIS Rapid Response Team

The National Hurricane Center expects little change in strength over the next 24 hours, but does expect Melissa to lose her tropical characteristics thereafter, so her life as a will be quite short.

Melissa's center was located near latitude 35.6 north and longitude 47.7 west, about 1,155 miles/1,860 km west of the Azores. The Azores is a group of nine volcanic islands in the North Atlantic Ocean. The island group is about 1,500 km/930 miles west of Lisbon, Portugal.

Melissa is moving toward the east-northeast near 30 mph/48 kph and this general motion is expected to continue during the next couple of days. The estimated minimum central pressure is 988 millibars.

This video is not supported by your browser at this time.
This is a simulated 3-D flyby animation over subtropical storm Melissa using TRMM satellite data on Nov. 20 at 6:21 a.m. EST. Red indicates heavy rainfall. Credit: SSAI/NASA, Hal Pierce

Although Melissa is far from land, the storm is still generating large ocean swells, rip currents, and dangerous surf in Bermuda, parts of the Northern Leeward Islands, Puerto Rico and Hispaniola today.

The National Hurricane Center expects Melissa to continue moving northeast and pass north of the Azores.

Explore further: Strong quake hits east Indonesia; no tsunami threat

add to favorites email to friend print save as pdf

Related Stories

NASA sees Tropical Storm Raymond fading fast

Oct 29, 2013

Satellite data showed some recent convective activity within Tropical Storm Raymond on Oct. 28 but southwesterly wind shear and cooler ocean temperatures are predicted by the National Hurricane Center to ...

NASA satellites see Cyclone 03A make landfall in Somalia

Nov 12, 2013

Tropical Cyclone 03A made landfall in Somalia and moved inland where it is dissipating over eastern Ethiopia today, Nov. 12. NASA's Aqua, Terra and TRMM satellites passed over the cyclone an captured images ...

Recommended for you

Strong quake hits east Indonesia; no tsunami threat

8 hours ago

A strong earthquake struck off the coast of eastern Indonesia on Sunday evening, but there were no immediate reports of injuries or damage, and authorities said there was no threat of a tsunami.

Scientists make strides in tsunami warning since 2004

Dec 19, 2014

The 2004 tsunami led to greater global cooperation and improved techniques for detecting waves that could reach faraway shores, even though scientists still cannot predict when an earthquake will strike.

Trade winds ventilate the tropical oceans

Dec 19, 2014

Long-term observations indicate that the oxygen minimum zones in the tropical oceans have expanded in recent decades. The reason is still unknown. Now scientists at the GEOMAR Helmholtz Centre for Ocean Research ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.