Hurricane Danielle became the first major hurricane of the 2010 Atlantic hurricane season overnight as it continued to make its way through the central Atlantic.

Danielle, which had been a Category 2 storm the day before with sustained winds estimated at around 95 knots (~110 mph) by the National Hurricane Center, quickly intensified overnight and by morning was a power Category 4 hurricane on the Saffir-Simpson scale with sustained winds of 115 knots (132 mph).

“The TRMM satellite passed directly over Danielle during the night and captured remarkable images as the storm was in the process of intensifying,” said Steve Lang, research meteorologist on the TRMM team in the Mesoscale Atmospheric Processes Branch at NASA’s Goddard Space Flight Center in Greenbelt, Md.

Two images were taken from TRMM at 06:46 UTC (2:46 a.m. EDT) on August 27. The first image showed a top-down view of the horizontal pattern of rain intensity within the storm. Rain rates in the center of the swath are from the TRMM Precipitation Radar (PR), and those 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), and are created at NASA Goddard. TRMM is managed by both NASA and the Japanese Space Agency, JAXA.

A trough is an elongated area of low pressure and that’s what the remnants of the once major hurricane known as Darby are becoming today. On June 28 at 6:55 p.m. EDT NASA and the Japanese Space Agency’s Tropical Rainfall Measuring Mission (TRMM) satellite captured isolated areas of rainfall off the western Mexico coast from Darby’s remnants.

The center of Darby the remnant low pressure area is located near 15 North and 97.5 West. Those remnants are still showing some scattered moderate to strong convection (rapidly rising air that creates clouds and thunderstorms) southwest of its center. Isolated strong convection likely associated with a nearby tropical wave is also being seen over the Gulf of Tehauntepec and within 60 nautical miles of the Mexican coast between 98 West and 101 West.

Darby’s remnants still have southwest to westerly winds between 20 and 25 knots (23-28 mph). The National Hurricane Center noted that “Darby should weaken to an open trough later today then extend northwest to Caribbean Tropical Storm Alex. The trough will move northwest in tandem with Alex over the next few days.”