The RapidScat instrument saw the strongest winds in the Central Pacific Ocean's Tropical Storm Niala were on the northwestern side, facing the Big Island of Hawaii while the rest of the storm was below tropical-storm strength.
At 1 p.m. EDT on September 26 the International Space Station (ISS) passed over Tropical Storm Niala. The RapidScat instrument that flies aboard ISS identified the strongest area of sustained winds in the northwestern quadrant of the storm at a rate of 24 meters per second (53.6 mph/86.4 kph). Sustained winds around the rest of the system were a lot weaker, near 9 meters per second (20 mph/32 kph) or less.
By Sept. 28 at 11 a.m. EDT, when NOAA's GOES-West satellite captured an infrared image of the storm south of the Big Island of Hawaii, Niala had weakened to a tropical depression. To the east of Niala is a developing tropical low pressure area.
The National Hurricane Center said that environmental conditions are expected to be conducive for development of that system, and a tropical depression is likely to form later this week while the low moves east-northeastward to northeastward.
At 11 a.m. EDT (5 a.m. HST/1500 UTC) on September 28, the center of Tropical Depression Niala was located near latitude 15.0 north and longitude 156.8 west. That puts the center of Niala about 440 miles (710 km) south of Honolulu, Hawaii and about 850 miles (1,370 km) east of Johnston Island.
The depression was moving toward the west-southwest near 8 mph and is expected to continue in that general direction for the next day. Maximum sustained winds were near 35 mph (55 kph) and additional weakening is expected during the next couple of days.
NOAA's Central Pacific Hurricane Center expects Niala to weaken to a remnant low later in the day on September 28.
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