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Hurricane Season 2010: Hurricane Darby (Eastern Pacific Ocean)
06.29.10
 
June 29, 2010

NASA's TRMM satellite captured scattered rainfall from the remnants of Darby &rsaquo View larger image
On June 28 at 2255 UTC (6:55 p.m. EDT) NASA's TRMM satellite captured scattered rainfall off the western Mexico coast from the remnants of Darby (blue and green).
Credit: NASA TRMM, Hal Pierce
TRMM Satellite Sees Darby's Remnants Still Kicking Up Isolated Showers

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."

Text credit: Rob Gutro/NASA's Goddard Space Flight Center



June 28, 2010

An infrared image of Darby (right) and Celia (left) from NASA's Aqua satellite AIRS instrument was captured on June 27 &rsaquo View larger image
This infrared image of Darby (right) and Celia (left) from NASA's Aqua satellite AIRS instrument was captured on June 27 at 0853 UTC (4:53 a.m. EDT) showed a very small center of remaining strong convection (purple) and thunderstorms in Darby's center and no strong convection in Celia's center.
Credit: NASA JPL, Ed Olsen
Celia and Darby are Now Both Weakening Tropical Storms

The Eastern Pacific twins, Darby and Celia were once both major hurricanes and today are just barely hanging on to tropical storm status. Both are forecast to continue weakening over the next day or two.

Celia is spinning farthest away from land in the Eastern Pacific and seems to be sitting still. At 5 a.m. EDT on Monday, June 28, Celia was located about 1070 miles (1720 km) west-southwest of the southern tip of Baja California. Celia is virtually stationary, moving only 2 mph (4 km/hr) to the southwest. Celia's maximum sustained winds were near 40 mph, but she expected to weaken and become a remnant low pressure area over the next day or two. Minimum central pressure is 1005 millibars.

Tropical Storm Darby is closer to the western Mexico coast, about 240 miles (390 km) south of Zihuatanejo, Mexico, near 14.2 North and 101.4 West. Darby's maximum sustained winds were also near 40 mph, but like Celia, Darby is expected to weaken to a remnant low pressure area by sometime on Tuesday. Darby is moving east-northeast toward the Mexican coast at 6 mph (9 km/hr) although no watches or warnings are posted for this storm. Current minimum central pressure is 1004 millibars.

NASA's Aqua satellite passed over Celia and Darby on June 25, and NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) instrument captured visible images of each storm. The MODIS team at NASA's Goddard Space Flight Center in Greenbelt, Md. created a mosaic of images from that data, and they can be found at: http://rapidfire.sci.gsfc.nasa.gov/gallery/?2010176-0625/CeliaDarby.A2010176.2140.

By Wednesday, the tropical twins should both be remnant low pressure areas in the Eastern Pacific.

Text credit: Rob Gutro/NASA's Goddard Space Flight Center



June 25, 2010

The GOES-13 satellite captures a powerful Hurricane Celia &rsaquo View larger image
This GOES-13 Satellite imagery from June 25 shows the powerful Hurricane Celia (left) with the larger eye, and behind it is Hurricane Darby (right) with a much smaller eye.
Credit: NASA GOES Project
GOES-13 Captures 2 Major Hurricanes: Darby Trailing Celia

There are now two major hurricanes in the Eastern Pacific Ocean and they appear to be chasing each other in imagery from the GOES-13 satellite. Hurricane Celia is a Category Five hurricane on the Saffir-Simpson Scale, and Hurricane Darby to Celia's east has just become a Category Three hurricane (a major hurricane).

The Geostationary Operational Environmental Satellite called GOES-13 captured a visible image of both the Category 5 Hurricane Celia and the Category 3 Hurricane Darby (located to Celia's southeast). In the satellite image from June 25 at 14:45 UTC (10:45 a.m. EDT) Celia had the larger eye of the two hurricanes.

The satellite image was created by NASA's GOES Project, located at NASA's Goddard Space Flight Center, Greenbelt, Md. GOES-11 is operated by the National Oceanic and Atmospheric Administration.

On Friday, June 23, at 11 a.m. EDT, Darby was classified as a major hurricane by the National Hurricane Center (NHC) as it had maximum sustained winds near 115 mph (185 km/hr). Darby was about 245 miles (395 km) south-southwest of Acapulco, Mexico, near 13.6 North and 101.2 West.

Darby was moving west-northwest near 7 mph (11 km/hr), although the NHC expects that to change over the weekend. NHC expects Darby to dip to the south then curve back toward the east by early next week while weakening. Darby's minimum central pressure is near 962 millibars.

Although Darby doesn't pose a threat to any land areas over the weekend, residents of western Mexico, including the Acapulco area, should closely monitor the track of this storm. Based on the National Hurricane Center's forecast track map, Darby could bring the western Mexican coast some rainfall and gusty winds by early next week.

Text credit: Rob Gutro/NASA's Goddard Space Flight Center



June 24, 2010

NASA's Aqua satellite captured an infrared image of Darby's clouds. &rsaquo View larger image
On June 24 at 08:23 UTC (4:23 a.m. EDT), NASA's Aqua satellite captured an infrared image of Darby's clouds, hours before it achieved hurricane status. The infrared imagery showed very high, cold thunderstorm cloud tops in the southeast and northern quadrants of the storm (purple) indicating strong convection.
Credit: NASA JPL, Ed Olsen
NASA's Terra satellite captured this visible image of Darby as a tropical storm &rsaquo View larger image
NASA's Terra satellite captured this visible image of Darby as a tropical storm on June 23 at 17:05 UTC (1:05 p.m. EDT) off western the Mexican coast.
Credit: NASA Goddard/MODIS Rapid Response Team
NASA Infrared Imagery Hinted Darby Would Become a Hurricane

Infrared imagery provides forecasters with a look at the temperature of cloud tops in tropical cyclones, sea surface and land surface temperatures and more. NASA infrared imagery from the morning of June 24 revealed that Darby had strong convection that is an indicator of a strengthening storm. Tropical Storm Darby became the second hurricane of the Eastern Pacific Ocean season this morning.

When NASA's Aqua satellite flew over Darby on June 24 at 08:23 UTC (4:23 a.m. EDT), the Atmospheric Infrared Sounder (AIRS) instrument onboard the satellite captured an infrared image of Darby's clouds, hours before it achieved hurricane status. The infrared imagery showed very high, cold thunderstorm cloud tops in the southeast and northern quadrants of the storm indicating strong convection. Convection is rapidly rising air the condenses and forms clouds (and in a tropical cyclone, it forms the thunderstorms that power the cyclone).

At 11 a.m. EDT (8 a.m. PDT) on June 24, the National Hurricane Center announced that Darby achieved hurricane status, making it the second hurricane of the Eastern Pacific Ocean season, just after Celia, which is spinning at sea much farther west. Hurricane Darby has maximum sustained winds near 75 mph, making it a category one hurricane on the Saffir-Simpson scale. (Category one hurricanes begin at 74 mph). Darby is located about 235 miles (375 km) south-southwest of Puerto Escondido, Mexico, near 12.8 North and 98.7 West. Darby is moving west near 9 mph (15 km/hr) and has a minimum central pressure near 990 millibars.

The National Hurricane Center forecasters expect vertical wind shear (winds that can tear a tropical cyclone apart) to remain light, so there's an opportunity for Darby to strengthen a little over the next couple of days before the winds increase.

Text credit: Rob Gutro/NASA's Goddard Space Flight Center






June 23, 2010

NASA AIRS satellite captures tropical storm Darby. &rsaquo View larger image
This infrared satellite image of Darby was captured from NASA's Aqua satellite on June 22 at 19:23 UTC (3:23 p.m. EDT). There is a large area of strong convection (purple) to the north of Darby's center where cloud tops were as cold as or colder than -63 degrees Fahrenheit.
Credit: NASA JPL, Ed Olsen
NASA's Infrared Satellite Imagery Sees Tropical Storm Darby Form Quickly The fifth tropical depression of the Eastern Pacific Ocean hurricane season developed and quickly strengthened into Tropical Storm Darby during the early morning hours of June 23. NASA's Aqua satellite captured a large area of strong convection that indicated that speedy strengthening.

Darby formed off the western Mexico coast south of the Gulf of Tehuantepec. At 5 p.m. EDT on June 22 Darby was located about 540 miles south-southeast of Salina Cruz, Mexico. That's near 11.5 North and 94.0 West.

Earlier on June 22, at 19:23 UTC (3:23 p.m. EDT), NASA's Aqua satellite flew over the low pressure area that became classified as Tropical Depression Darby and provided forecasters with a look at the convection happening in the storm. Infrared satellite imagery from the Atmospheric Infrared Sounder (AIRS) instrument indicated a large area of strong convection to the north of Darby's center where cloud tops were as cold as or colder than -63 degrees Fahrenheit. Infrared satellite data is helpful to forecasters in determining the convection (rapidly rising air that condenses and forms clouds and thunderstorms). Strong convection, like that seen in Darby is indicative of a strengthening tropical cyclone.

Darby's maximum sustained winds had increased to 40 mph with higher gusts by 5 a.m. EDT on June 23. Tropical storm-force winds extend outward up to 50 miles to the west of the center. Additional strengthening is also expected in the next 48 hours. Estimated minimum central pressure is 1005 millibars.

Darby is moving to the northwest near 9 mph, but is expected to turn toward the west-northwest and then west over the next day. Residents from Acapulco north to Manzanillo, Mexico should watch the track of Darby over the next several days.

Text credit: Rob Gutro/NASA's Goddard Space Flight Center