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Hurricane Season 2012: Tropical Depression John (Eastern Pacific Ocean)
09.05.12
 
AIRS infrared data on Sept. 4 at 5:23 p.m. EDT showed a circular swirl of clouds in post-tropical storm John › View larger image
NASA AIRS infrared data on Sept. 4 at 5:23 p.m. EDT showed a circular swirl of clouds in post-tropical storm John where temperatures were around (yellow) 270 kelvin (26.3 F/-3.1 C), which are warm in terms of cloud top temperatures for thunderstorms.
Credit: NASA JPL, Ed Olsen
NASA Sees Fading Post-Tropical Cyclone John's Warmer Cloud Tops

Post-tropical cyclone John has been "flushed" out of existence in the eastern Pacific Ocean, and infrared NASA imagery revealed warmer cloud top temperatures and virtually no precipitation from John's remnants on Sept. 4.

When NASA's Aqua satellite flew over post-tropical storm John on Sept. 4 at 21:23 UTC (5:23 p.m. EDT) the Atmospheric Infrared Sounder (AIRS) instrument revealed that cloud top temperatures in the storm had warmed over the previous 24 hours. AIRS data also showed there was one very tiny area of convection (rising air that forms the thunderstorms that make up a tropical cyclone) in the southwestern quadrant of the entire low pressure area. The AIRS infrared data showed a circular swirl of clouds where temperatures were around 270 kelvin (26.3 F/-3.1 C), which are warm in terms of cloud top temperatures for thunderstorms. When cloud top temperatures reach the AIRS data threshold of -63F/-52C, they are considered strong thunderstorms.

The last advisory on John was issued by the National Hurricane Center on Sept. 4 at 2100 UTC (5 p.m. EDT), just before the AIRS image was captured by NASA's Aqua satellite. The 5 p.m. advisory put John's center about 505 miles west-northwest of Cabo San Lucas, Mexico, near 24.3 North and 117.7 West. John's maximum sustained winds were near 35 mph (55 kmh) and weakening. The remnants of John were moving to the northwest at 12 knots (13.8 mph/22.2 kmh) as the low pressure area continued to weaken. John is expected to dissipate later today.

Text Credit: Rob Gutro
NASA Goddard Space Flight Center, Greenbelt, Md.



Sep. 4, 2012

NASA's Aqua satellite flew over John on Sept. 3 at 2041 UTC (4:41 p.m. EDT) during its brief time as a tropical storm › View larger image
NASA's Aqua satellite flew over John on Sept. 3 at 2041 UTC (4:41 p.m. EDT) during its brief time as a tropical storm and noticed the strongest convection (purple) and coldest cloud top temperatures seemed to be limited to the northeastern and southwestern quadrants of the storm.
Credit: NASA JPL, Ed Olsen
NASA Sees the Short Life of Tropical Depression John

Tropical Storm John had about one day of fame in the Eastern Pacific. Born Tropical Depression 10, it intensified into Tropical Storm John on Sept. 2 at 5 a.m. EDT and maintained maximum sustained winds of 40 mph (65 kmh) until it weakened back into a depression on Monday, Sept. 3 at 11 p.m. EDT.

NASA's Aqua satellite flew over John on Sept. 3 at 2041 UTC (4:41 p.m. EDT) during its brief time as a tropical storm and noticed convection (rising air that forms thunderstorms that make up the storm) and coldest cloud top temperatures seemed to be limited to the northeastern and southwestern quadrants of the storm. As John continued to move north into cooler waters the convection tapered off, and the development of strong thunderstorms diminished.

By Tuesday, September 04, 2012 at 2 a.m. EDT, there was no sign of strong convection in John and the storm had become "a swirl of low- to mid-level clouds," according to the National Hurricane Center.

At 11 a.m. EDT today, Tropical Depression John's maximum sustained winds were near 35 mph (55 kmh) and the storm is weakening. It was centered about 420 miles (620 km) west of the southernmost tip of Baja California, near 23.5 North and 116.5 West. John was moving to the northwest near 14 mph (22 kmh) and is expected to keep moving in that general direction while slowing over the cooler waters.

John's fame is fleeting as the tropical depression is expected to become a remnant area of low pressure later today, Sept. 4.

Text Credit: Rob Gutro
NASA Goddard Space Flight Center, Greenbelt, Md.



Sep. 2, 2012

GOES satellite image of Isaac, Kirk, Leslie, and Tropical Depression 10E › View larger image
Tropical Depression Isaac's Remnants continued soaking the Ohio Valley and are moving into the Mid-Atlantic, while Kirk became post-tropical in the northern Atlantic, Tropical Storm Leslie is strengthening and headed north. In the Eastern Pacific, Tropical Depression 10E was born.On Sept. 2 at 7:45 p.m. EDT, the NASA GOES Project created this infrared image from NOAA's GOES-13 satellite that showed all four storms.
Credit: NASA GOES Project
NASA Sees Atlantic Storms Isaac, Kirk and Leslie, and E. Pacific TD10E

On Sunday, Sept. 2, Tropical Depression Isaac's Remnants continue soaking the Ohio Valley and are moving into the Mid-Atlantic, while Kirk became post-tropical in the northern Atlantic, Tropical Storm Leslie is strengthening and headed north. In the Eastern Pacific, Tropical Depression 10E was born. All of these storms were captured in one panoramic image created by NASA from NOAA's GOES-13 satellite on Sunday, Sept. 2, 2012

On Sept. 2 at 7:45 p.m. EDT, the NASA GOES Project at the NASA Goddard Space Flight Center in Greenbelt, Md. created infrared image from NOAA's GOES-13 satellite that showed all four storms.

Kirk Becomes Post-Tropical

At 5 p.m. EDT on Sept. 2, Kirk became Post-tropical storm Kirk Hurricane Kirk's with maximum sustained winds near 50 mph (85 kmh). Kirk was about 965 miles (1,550 km) east-northeast of Cape Race, Newfoundland near 49.7 North and 30.1 West. It was speeding to the north 47 mph (76 kmh) and had a minimum central pressure of 1002 millibars. That was the last position noted in the final bulletin from the National Hurricane Center. Additional information on this system can be found in high seas forecasts issued by the United Kingdom Meteorological office.


Tropical Storm Leslie Intensifying Again, Turning North

Tropical Storm Leslie weakened and is now expected to intensify as it turns north. The National Hurricane Center expects Leslie to become a hurricane before reaching Bermuda. On Sept. 2 at 5 p.m. EDT Leslie had maximum sustained winds near 60 mph (95 kmh), and was located about 370 miles (590 km) north of the Leeward Islands, near latitude 22.4 north and longitude 61.3 west. Leslie is moving northwest near 10 mph (17 kmh).

The National Hurricane Center noted that Leslie is generating rough surf that is affecting the Leeward Islands and will begin affecting Puerto Rico and the Virgin Islands during the night on Sept. 2, and during Sept. 3. The GOES-13 satellite imagery indicates strong northwesterly wind shear, where clouds and showers are pushed to the southeast of the center of circulation.


Isaac's Remnants Affecting Ohio and Tennessee Valleys

Isaac is merging with a frontal zone and moving through the Ohio Valley. The remnants associated with a low pressure center were located over Illinois on Sept. 2. East of the low pressure center, the frontal boundary was draped over southern West Virginia and into North Carolina. West of the low, a frontal boundary stretched back through the Tennessee Valley. The low pressure center is expected to crawl eastward over southern Indiana on Sept. 3, and over northern Kentucky on Sept. 4, bringing showers and thunderstorms with it as it crawls east.


Eastern Pacific: Tropical Depression 10 E Forms, Ileana Fizzles

Tropical Storm Ileana fizzled early on Sunday, Sept. 2 and Tropical Depression 10E was born.

At 11 a.m. EDT on Sept. 2, Ileana had become a post-tropical depression with maximum sustained winds near 30 mph (45 kmh). The last advisory from the National Hurricane Center was issued at that time, and Ileana was located near latitude 22.6 north and longitude 122.5 west. The remnant low is moving toward the west near 12 mph (19 kmh). Ileana's remnants are expected to turn west-southwest on Sept. 3. Ileana appears as a large area of clouds to the northwest of Tropical Depression 10E on the GOES-13 satellite image.

Tropical Depression 10E formed 320 miles (510 km) south of the southernmost tip of Baja California at 5 p.m. EDT on Sept. 3. It was centered near 18.3 North and 109.6 West. Tropical Depression 10E had maximum sustained winds near 35 mph (55 kmh) and was moving to the west-northwest at 17 mph (28 kmh). The National Hurricane Center noted that the storm could strengthen into a tropical storm on Sept. 3.

Text Credit: Rob Gutro
NASA Goddard Space Flight Center, Greenbelt, Md.