NASA Earth Observation GOES: Hurricane Iselle threatens Hawaii

Hurricane Iselle is pictured in the Eastern Pacific Ocean on August 3, 2014

Hurricane Iselle picked up strength in the open Pacific on Monday as the powerful storm barrelled toward Hawaii, US forecasters said.

The NOAA Miami-based National Hurricane Centre upgraded Iselle, now some 1,245 miles (2,005 kilometers) east of Hilo, Hawaii, to a Category Four storm on the five-level Saffir-Simpson scale.

Earlier Monday, it had been listed as a Category Three storm.

NOAA's GOES-West satellite captured this image of a very active Eastern and Central Pacific, hosting three tropical cyclones (from left to right) Genevieve, Iselle and Julio.

Image Credit: NASA/NOAA GOES Project

NASA and NOAA satellites have been supplying forecasters with data developing tropical cyclones in the Eastern and Central Pacific Ocean and over the last several days. There have been as many as five tropical systems at the same time.

On Monday, August 4, there were three tropical systems stretching from west to east: Tropical Depression Genevieve in the Central Pacific, Hurricane Iselle and Tropical Storm Julio in the Eastern Pacific.

This false-colored image represents infrared data on Tropical Storm Iselle on July 31 at 5:23 p.m. EDT from the AIRS instrument aboard NASA's Aqua satellite.

Image Credit: NASA JPL

Tropical Depression Genevieve Strengthens
On August 4, Tropical Depression Genevieve was located about 930 miles (1,495 km) southwest of Honolulu, Hawaii. Maximum sustained winds were still near 35 mph (55 kph).

Genevieve was moving westward at about 16 mph (26 kph). NOAA's Central Pacific Hurricane Center forecasts gradual strengthening late on August 4 and 5, so Genevieve could once again reach tropical storm status.

To the east of Genevieve lies low pressure area known as System 93C. It is producing disorganized showers and thunderstorms.

System 93C is located about 500 miles south of Hilo, Hawaii. This low pressure area is moving to the west at 15 mph and currently has a near zero percent chance of becoming a tropical depression over the next couple of days.