NASA's satellite imagery sees Hilda hit a wall

Aug 27, 2009
The Atmospheric Infrared Sounder (AIRS) instrument on the Aqua satellite saw Hilda's cold clouds on Aug. 26 at 7:29 a.m.EDT and didn't see an eye or the hallmark "comma shape" of the storm, just a rounded area of thunderstorms that indicated she was losing her punch. Credit: NASA JPL, Ed Olsen

Two days ago, Hilda was in prime shape to strengthen further as she tracked westward, far south of the Hawaiian Islands. Today, as a result of winds and cooler waters, she's weakened to a tropical depression, and NASA satellites helped confirm that looking at her waning winds and thunderstorms.

The Atmospheric Infrared Sounder (AIRS) instrument on the Aqua observes Hilda's cold clouds, which is an indication of strength. The colder the thunderstorms, the higher and more powerful they are, but Hilda didn't show any. AIRS imagery also didn't see an eye or the hallmark "comma shape" of the storm, just a rounded area of thunderstorms that indicated she was losing her punch.

NASA's QuikScat satellite captured Tropical Depression Hilda's winds using its microwave imagery to peer through its clouds on Aug. 26 at 12:26 a.m. EDT). The strongest winds are represented in the center of circulation in the red area, which are about 34 mph. White barbs point to the few areas of heavy rain near Hilda's center. Credit: NASA JPL, Peter Falcon

NASA's QuikScat satellite also watched Hilda's winds slow from tropical storm to tropical depression-force today, August 27.

Like the Aqua satellite, every day, NASA's captures data from tropical cyclones. QuikScat reads the rotating surface wind speeds of tropical cyclones using its microwave imagery to peer through their clouds. QuikScat data are used to make images that show wind speeds in different colors and wind direction are indicated by small barbs. The highest speeds are normally shown in purple, which indicate winds over 40 knots (46 mph), but QuikScat today revealed that Hilda's highest winds in the center were only near 34 mph.

Hilda's sustained winds were near 34 mph, and fading because of the cooler waters she's moved into. Her center is located near 13.7 north and 152.5 west
She was moving west-southwest near 9 mph, and will continue tracking south of the Hawaiian Islands.

She's not expected to totally dissipate until Monday, August 31.

Source: NASA/Goddard Space Flight Center

Explore further: NASA and NOAA's nighttime and daytime views of the blizzard of 2015

add to favorites email to friend print save as pdf

Related Stories

NASA satellites see remnant low Dolores go out kicking

Jul 17, 2009

The remaining clouds and showers that were once tropical storm Dolores are fading at sea, more than 940 miles west of Cabo San Lucas, Mexico. Dolores has now weakened into a remnant low pressure area but continues ...

Recommended for you

On the right track for tropical clouds

18 hours ago

Think of a tropical storm about the size of Alaska. Large and lumbering, the Madden-Julian Oscillation (MJO) affects weather patterns in every corner of the world. Unlike its well-known cousin El Niño, the ...

SMAP will track a tiny cog that keeps cycles spinning

20 hours ago

When you open the back of a fine watch, you see layer upon layer of spinning wheels linked by interlocking cogs, screws and wires. Some of the cogs are so tiny they're barely visible. Size doesn't matter—what's ...

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.