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Hurricane Season 2009: Andres (Eastern Pacific)
06.25.09
 
June 25, 2009

NASA's TRMM satellite could barely detect circulation or much rainfall on June 24 when it passed overhead > Larger image NASA's TRMM satellite could barely detect circulation or much rainfall on June 24 when it passed overhead.
Credit: NASA/SSAI, Hal Pierce
NASA's Aqua satellite saw that Andres thunderstorms were losing punch because the clouds weren't as cold > Larger image NASA's Aqua satellite saw that Andres thunderstorms were losing punch because the clouds weren't as cold as they were when it was a tropical storm. Andres' center is the comma-like blue shape over the open ocean.
Credit: NASA JPL, Ed Olsen
Two NASA Satellites Catch Andres' Last Breath

In the early afternoon hours of June 24, the once-hurricane Andres breathed his last in the waters of the eastern Pacific Ocean, and two NASA satellites were there for him. NASA's Tropical Rainfall Measuring Mission watched as Andres' rainfall waned, and NASA's Aqua satellite watched as his clouds became less cold, lower, and weaker.

At 2 p.m. EDT on June 24, the National Hurricane Center wrote Andres' eulogy: "Andres has been devoid of deep convection near the center for about 12 hours and given its environment the convection is not likely to return. Andres has therefore degenerated into a remnant low and this will be the last advisory on this system."

He was seen at 2 p.m. EDT near latitude 21.5 north and longitude 107.6 west, or about 145 miles west-northwest of Cabo Corrientes, Mexico.

Just a remnant low pressure area by the late afternoon, what was once Andres turned northward to dissipate into the sunset.

The Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua satellite captured its last infrared image of Andres' cold clouds on June 24 at 4:53 a.m. EDT (8:53 UTC) when he was still a tropical depression. The center of the storm appears to be a "comma-like" shape over the ocean.

The satellite revealed that there were no high, strong thunderstorm clouds in Andres, a sign of a very weak system. The false-colored images depict the highest, coldest clouds in purple, and then blue. The storm only had the lower clouds (in blue) that are as cold as 240 degrees Kelvin, or minus 27F.

One and one half hours later, NASA's Tropical Rainfall Measuring Mission barely found circulation and rainfall in Andres when the satellite passed directly overhead on June 24 at 6:22 a.m. EDT (1022 UTC).

Text credit: Rob Gutro, NASA's Goddard Space Flight Center



June 24, 2009

NASA's AIRS instrument captured the coldest thunderstorm cloudtops in Andres when he was a hurricane briefly on June 23. > Larger image NASA's AIRS instrument captured the coldest thunderstorm cloudtops in Andres when he was a hurricane briefly on June 23. The highest, coldest clouds are in purple, in the center of the storm. Credit: NASA/JPL, Ed Olsen Andres Ripped In and Out of Hurricane Status, Now Shearing Apart

Andres managed to make a "Category One" hurricane status briefly late on June 23, before dropping back down to tropical storm status and moving away from western Mexico early on June 24. Now, wind shear is ripping the storm apart.

At 5 p.m. EDT on June 23, Andres managed to become a Category One hurricane with maximum sustained winds near 65 knots (74 mph) when it was 65 miles west-southwest of Manzanillo, Mexico. Andres' hurricane strength didn't last long, though.

The National Hurricane Center (NHC) discussion on June 24 at 5 a.m. EDT indicated that Andres was being battered by wind shear (winds blowing at different directions at different levels of the atmosphere that tear a storm apart). The NHC said, "Satellite images show a deteriorating cloud pattern associated with the storm...as a ragged-looking mass of deep convection is being sheared southwestward away from the estimated low-level center. It appears that Andres is succumbing to the persistent east-northeasterly shear that has been impacting it over the past day or two."

On June 24 at 2 a.m. PDT (5 a.m. EDT) the center of Tropical Storm Andres was near latitude 19.5 north and longitude 106.7 west or about 90 miles south of Cabo Corrientes, Mexico and about 315 miles southeast of the southern tip of Baja California, Mexico. Maximum sustained winds were near 60 mph, and weakening is expected. Andres is moving toward the northwest near 3 mph and will continue in that direction and speed.

NASA's Aqua satellite flew over Andres on June 23 at 4:41 p.m. EDT (2041 UTC), and captured an infrared image of the storm's clouds. The Atmospheric Infrared Sounder (AIRS) is the instrument that flies aboard NASA's Aqua satellite and it managed to see Andres during the short time that it was a hurricane. The AIRS image shows the temperature of Andres' high, cold thunderstorm cloud tops. The coldest cloud temperatures are in purple and are seen in the center of the storm.

Tropical Storm Andres is now expected to weaken to a tropical depression before Thursday night, June 25.

Text credit: Rob Gutro, NASA's Goddard Space Flight Center



June 23, 2009

Tropical Storm Andres is seen in the middle of this GOES-11 satellite image, next to the western Mexican coast > Larger image Tropical Storm Andres is seen in the middle of this GOES-11 satellite image, next to the western Mexican coast.
Credit: NASA/NOAA GOES Project
Andres on the Hurricane Edge

Tropical Storm Andres continues to batter the western Mexican coast with winds near 70 mph, about 4 mph shy of a category one hurricane.

At 2 p.m. EDT (11 a.m. PDT) on Tuesday, June 23, Andres' center was about 55 miles south-southwest of Manzanillo, Mexico, near 18.4 degrees north latitude and 104.8 degrees west longitude. Andres is moving northwest near 12 mph, tracking along the western Mexico coastline. Andres is expected to make a turn west-northwest and brush the Baja California on Thursday, June 25. Its central pressure is 988 millibars.

In general, Andres is dropping between 3 and 6 inches of rainfall over portions of west-central Mexico, but some isolated amounts up to 8 inches may be seen. Between the heavy rainfall and the storm surge of 1-3 feet above normal, and the tropical storm force winds that extend out to 70 miles from the center, the storm is wreaking havoc on the coast.

The Geostationary Operational Environmental Satellite, GOES-11, captured Andres at 2 p.m. EDT (1800 UTC) on June 23 near the Mexican coast. GOES-11 is operated by the National Oceanic and Atmospheric Administration, and the image was created by NASA's GOES Project, located at NASA's Goddard Space Flight Center, Greenbelt, Md.

Andres is forecast to turn away from the coast and start weakening sometime on June 24.

Text credit: Rob Gutro, NASA's Goddard Space Flight Center



TRMM captured Tropical Storm Andres Rainfall > Larger image TRMM captured Tropical Storm Andres Rainfall
Credit: NASA/SSAI, Hal Pierce
TRMM Sees That Tropical Storm Andres Has a Good Circulation

The East Pacific hurricane season officially began on May 15 and runs through November 30. This year Tropical Storm Andres became the first named storm of the season after forming about 180 miles off of the southwestern coast of Mexico on the evening (local time) of June 21. Less than a week earlier, the first Tropical Depression 1E (TD #1E) of the season formed farther to the north before dissipating near the Mexican coast in the vicinity of Mazatlan. Andres originated from the 2nd depression of the season (TD #2E), which formed on the afternoon of June 21. After becoming a tropical storm, Andres has moved generally northward towards the Mexican coast.

The Tropical Rainfall Measuring Mission satellite (known as TRMM) was placed into service in November of 1997. From its low-earth orbit, TRMM has been providing valuable images and information on tropical cyclones around the Tropics using a combination of passive microwave and active radar sensors, including the first precipitation radar in space. TRMM captured this image of Andres as it was moving northward towards the southwestern coast of Mexico. The image was taken at 10:36 UTC (3:36 am PDT) June 22, 2009 and shows the horizontal distribution of rain intensity within the storm. Rain rates in the center swath are from the TRMM Precipitation Radar (PR), and rain rates in the outer swath are from the TRMM Microwave Imager (TMI). The rain rates are overlaid on infrared (IR) data from the TRMM Visible Infrared Scanner (VIRS).

TRMM reveals that Andres does not have a well-defined eye but does have a fairly broad circulation as evidenced by the curvature in the rain bands. TRMM also shows that most of the rain is south and west of the center. The green and blue areas indicate moderate to light intensity rain, respectively. At the time of this image, Andres was a moderate tropical storm with sustained winds estimated at 45 knots (~50 mph) by the National Hurricane Center. Andres is expected to turn to the northwest parallel to the coast and to slowly intensify possibly into the first hurricane of the season.

TRMM is a joint mission between NASA and the Japanese space agency JAXA.

Text credit: Steve Lang, SSAI / Goddard Space Flight Center



June 22, 2009

This infrared image of Andres was created by data from the Atmospheric Infrared Sounder (AIRS), an instrument that flies aboard NASA's Aqua satellite. > Larger image
Credit: NASA JPL, Ed Olsen
Tropical Storm Andres Forms in Eastern Pacific

The first tropical storm of the Eastern Pacific Hurricane season has formed off the coast of southwestern Mexico. Andres formed on Sunday, June 21 and is now headed northwest while strengthening.

Andres' maximum sustained winds are near 50 mph with higher gusts. The National Hurricane Center said that Andres could also become the Eastern Pacific Ocean's first hurricane of the season in a couple of days.

At 5 a.m. PDT (8 a.m. EDT) the center of Tropical Storm Andres was near latitude 15.2 north...longitude 102.0 west or about 180 miles south of Zihuatanejo, Mexico and about 325 miles south-southeast of Manzanillo, Mexico.

Andres is moving toward the northwest near 3 mph and a slow northwest motion is expected to continue during the next 24 to 48 hours. This infrared image of Andres was created by data from the Atmospheric Infrared Sounder (AIRS), an instrument that flies aboard NASA's Aqua satellite. The image was created on June 21 at 4:23 a.m. EDT (0823 UTC).

The AIRS image shows the temperature of Andres' high, cold thunderstorm cloud tops. The coldest cloud temperatures are in purple. The center of the storm is near what looks like a sideways number eight. The other high clouds around it are also part of the storm, flowing outward from the center. The AIRS data creates an accurate 3-D map of atmospheric temperature, water vapor and clouds, all of which are helpful to forecasters.

A tropical storm watch remains in effect from Zihuatanejo, Mexico northward to Manzanillo, Mexico. A tropical storm watch means that tropical storm conditions are possible within the watch area, generally within 36 hours.

Text credit: Rob Gutro, NASA's Goddard Space Flight Center