NASA’s Aqua Sees Weakening Hurricane Ignacio Nearing Hawaiian Islands

NASA’s Aqua satellite has passed over Hurricane Ignacio, imaging the storm in infrared light and providing valuable temperature data. Aqua veiwed a weaker Ignacio moving parallel to the Hawaiian Islands.

Aqua’s Atmospheric Infrared Sounder (AIRS) gathers infrared data which indicates temperatures. The latest AIRS data was transformed into a false-colored infrared image from August 30 at 22:47 UTC showing high, cold, strong thunderstorms surrounding the center of Hurricane Ignacio.

Also revelaed by the AIRS imagery was a thick band of thunderstorms spiraling into the northern quadrant of the storm from the east.

The lowest cloud top temperatures were as cold as -63F/-53C around the center of the hurricane, a bit warmer than they were the day before. NASA research has shown that thunderstorms with cloud tops that cold and high in the troposphere have the potential to generate heavy rainfall.

As Ignacio weakens, those cloud tops will drop and become less cold. When infrared data shows that cloud tops are warmer, it means the uplift in the storm is weakening.

Barely Discernible

NOAA’s Central Pacific Hurricane Center (CPHC) today stated that infrared satellite images show that Ignacio continued to steadily weaken, down from a peak intensity that was reached on August 30, with a cloud-filled eye barely discernible.

Ignacio is moving toward the northwest near 10 mph (17 kph) and this motion Is expected to continue for the next couple of days.

The CPHC forecast calls for Ignacio to track in a general north-northwesterly direction over the next several days, paralleling the Hawaiian Islands to the east, but never making landfall. Ignacio is also forecast to weaken to a tropical storm by September 2 as it continues heading northwest.

Updated forecasts can be found on NOAA’s CPHC website.

Photo: false-colored infrared image from Aug. 30 at 22:47 UTC. Credit – NASA JPL, Ed Olsen