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Hurricane Season 2012: Tropical Storm Daniel (Eastern Pacific Ocean)
07.13.12
 
This GOES image, taken on July 13, 2012, shows the remnants of Hurricane Daniel south of Hawaii.› View larger image
This image was taken on July 13, 2012 at 1200 UTC from the GOES-15 satellite. It shows the remnants of Hurricane Daniel south of Hawaii. Click on the image to see Daniel followed further east by Tropical Storms Emilia and Fabio.
Credit: NASA GOES Project
Hurricane Daniel's Remnants Causing Wind in Hawaii

The Central Pacific Hurricane Center is tracking the remnants of Tropical Storm Daniel, and noted that on July 13, 2012 they were about 300 miles southeast of Hilo, Hawaii. The only effect the low will have on Hilo, Hawaii is an increase in the winds and it is not coming from the low, but because of it. NOAA's GOES-15 satellite captured Daniel's remnants south of Hawaii today while being "chased" by Tropical Storm's Emilia and Fabio.

NOAA's GOES-15 satellite took an image of Daniel's remnants on July 13, 2012 at 1200 UTC (8 a.m. EDT). It showed the remnants of Hurricane Daniel south of Hawaii followed further east by Tropical Storms Emilia and Fabio. The impressive image shows the three tropical cyclones lined up from west to east. The image was created by NASA's GOES Project, located at the NASA Goddard Space Flight Center in Greenbelt, Md.

A gradient is a rate of change with respect to distance of a variable quantity, as temperature or pressure, in the direction of maximum change. When a low pressure area comes close to a high pressure area, it creates a tighter or stronger gradient in pressure that increases winds. Wind is caused by air flowing from high pressure to low pressure. That's what's happening as Daniel's remnant low pressure area passes south of the state. T the main Hawaiian Islands reported today, July 13, that "generally moderate trade winds are blowing and air pressure trends supported an increase in wind speed."

The National Weather Service in Hawaii noted that "wind speeds will increase more quickly than the usual rule of thumb might suggest, especially closer to the low. By the same token wind speeds will decline more quickly again on Saturday."

The National Hurricane Center noted that conditions are not favorable for Daniels' re-development as it passes south of Hawaii. In fact, they're giving it a "near zero percent chance" of redeveloping over the weekend.

Text Credit: Rob Gutro
NASA's Goddard Space Flight CenterGreenbelt, Md.



July 12, 2012

This GOES-15 image from July 12, 2012 shows the remnants of former tropical storm Daniel heading toward Hawaii› View larger image
This GOES-15 image from July 12, 2012 shows the remnants of former tropical storm Daniel heading toward Hawaii, followed by Hurricane Emilia to the east, and further east is Tropical Storm Fabio.
Credit: NASA GOES Project
Satellite Sees Remnants of Former Tropical Storm Daniel

Daniel is no longer a tropical storm, and has weakened to a remnant low pressure system, but its circulation is still visible on satellite imagery today, July 12 as it moves south of Hawaii.

A visible image from NOAA's GOES-15 satellite on July 12, 2012 shows the circulation of Daniel's remnants heading toward Hawaii, followed by Hurricane Emilia to the east, and further east is Tropical Storm Fabio. Daniel's remnants appear as a ghost-like swirl of clouds in comparison to the organized and bright white clouds in powerful Hurricane Emilia.

The image was created by the NASA GOES Project, located at NASA Goddard Space Flight Center in Greenbelt, Md. NASA's GOES Project uses data from the NOAA satellite and creates images and animations. At that time it was still about 800 miles east-southeast of Hilo, Hawaii.

Daniel's remnants are forecast to pass to the south of Hawaii and will not affect the state.

Text Credit: Rob Gutro
NASA's Goddard Space Flight CenterGreenbelt, Md.



July 11, 2012

Slug: Satellite Sees Hurricane Emilia Chasing Tropical Storm Daniel


An animation of satellite observations from July 8 (6:00 p.m. EDT) to July 11 (1:30 p.m. EDT) shows Hurricane Daniel as it loses its hurricane eye and become a tropical storm as it heads toward Hawaii. East of Daniel, Emilia became a Category 4 hurricane on July 10 and weakened as it follows Daniel. Observations from NOAA's GOES-15 satellite. TRT :33 Super(s): Courtesy: NASA/NOAA GOES Project Center Contact: Rob Gutro (301) 286-4044 HQ Contact: Steve Cole (202) 358-0918 For more information: www.nasa.gov/hurricane




This analysis of sea surface temperatures is from July 8-10, 2012.› View larger image
This analysis of sea surface temperatures is from July 8-10, 2012. Daniel's predicted path (shown in white) takes it over water with temperatures of about 24-25 C (~75.2 to 77.0 F). The boundary of 26 C (~79 F ) temperatures are shown in yellow on this analysis.
Credit: NASA/SSAI, Hal Pierce
TRMM passed over Daniel on July 11, 2012 showing a few strong thunderstorms near Daniel's center of circulation› View larger image
TRMM passed over Daniel on July 11, 2012 at 0857 UTC. Surface rainfall near the storm's center was light to moderate (0.78 to 1.57 inches/20 to 40 mm/hr), appearing in yellow, blue and green. A few strong thunderstorms near Daniel's center of circulation were reaching to heights of over 11km (~6.8 miles). Radar reflectivity values of almost 42 dBZ were being returned to TRMM PR indicating that moderate to heavy rainfall (red) was occurring in that area.
Credit: NASA/SSAI, Hal Pierce
Tropical Storm Daniel was seen by the TRMM satellite on July 11, 2012 at 0858 UTC (4:58 a.m. EDT).› View larger image
Tropical Storm Daniel was seen by the TRMM satellite on July 11, 2012 at 0858 UTC (4:58 a.m. EDT). Daniel had only light to moderate rainfall – seen in the yellow, green and blue areas, where rain was falling between 20 and 40 millimeters (.78 to 1.57 inches) per hour.
Credit: SSAI/NASA, Hal Pierce
NASA Sees Tropical Storm Daniel Move Over Cooler Water

Tropical Storm Daniel was once a hurricane and now a rapidly weakening tropical storm as a result of moving over cooler waters. NASA's Tropical Rainfall Measuring Mission (TRMM) satellite provided a look at just how cool the waters are that have sapped Daniel's strength.

The TRMM satellite flew above weakening tropical storm Daniel on July 10, 2012 at 0003 UTC. TRMM's Microwave Imager (TMI) and Precipitation Radar (PR) data from that pass showed that only light to moderate rainfall (.0.78 to 1.57 inches/20 to 40 mm/hour) was occurring with the weakening storm.

At NASA's Goddard Space Flight Center in Greenbelt, Md. Hal Pierce of the TRMM team created an analysis that showed averaged Sea Surface Temperatures (SST). The SST data was derived from TRMM Microwave Imager (TMI) data for the period from July 8-10, 2012. Daniel's predicted path takes it over water with temperatures of about 24-25 C (~75.2 to 77.0 F). Water needs to be around 26 C (~79 F ) to fuel a tropical cyclone so Daniel is predicted to gradually weaken to a tropical depression over the next couple days.

At 5 a.m. EDT on July 11, 2012 Tropical Storm Daniel had maximum sustained winds near 40 mph (65 kmh) and was moving to the west near 16 mph (26 kmh). Daniel was about 1,055 miles (1,700 km) east-southeast of Hilo, Hawaii near 15.4 North and 139.7 West. Satellite data indicates that only a small area of deep convection (rising air that form the thunderstorms that make up the tropical cyclone) remains south and southeast of Daniel's center.

When TRMM passed over Daniel on July 11 at 0858 UTC, it observed a few strong thunderstorms near Daniel's center of circulation reaching to heights of over 11km (~6.8 miles). Radar reflectivity values of almost 42 dBZ were being returned to TRMM PR indicating that moderate to heavy rainfall was occurring in that area.

Daniel is crossing over into the central Pacific Ocean today. On Friday the weakening tropical depression is expected to be south-southeast of the Hawaiian Islands.

Text Credit: Hal Pierce / Rob Gutro
SSAI / NASA's Goddard Space Flight CenterGreenbelt, Md.


























July 10, 2012

NOAA's GOES-15 satellite captured three tropical cyclones spinning in the eastern Pacific Ocean today, July 10, 2012.› View larger image
NOAA's GOES-15 satellite captured the three tropical cyclones spinning in the eastern Pacific Ocean today, July 10, 2012 at 1200 UTC (8 a.m. EDT). Tropical Storm Daniel is farthest west, followed by major hurricane Emilia, and developing low pressure System 98E.
Credit: NASA/NOAA GOES Project
Satellite Sees Two Tropical Cyclones Chase Tropical Storm Daniel

A panoramic satellite image shows an active eastern Pacific Ocean with three tropical systems that appear to be chasing each other. Tropical Storm Daniel approaching the central Pacific Ocean, with major Hurricane Emilia further east, and a developing low pressure area east of Emilia.

In an image captured by NOAA's GOES-15 satellite, all three tropical cyclones were seen spinning in the eastern Pacific Ocean on July 10, 2012 at 1200 UTC (8 a.m. EDT).Daniel has weakened from a hurricane to a tropical storm and appears smaller than Hurricane Emilia. Daniel is about 180 miles in diameter, while Emilia is over 250 miles in diameter. System 98E, the low pressure system east of Emilia, is dwarfed by the large hurricane. NOAA manages the GOES-15 satellite, and NASA's GOES Project at the NASA Goddard Space Flight Center in Greenbelt, Md. uses the data to create images and animations of weather around the U.S.

Tropical Storm Daniel's winds were now down to 65 mph (100 kmh). At 8 a.m. PDT/11 a.m. EDT, the center of Tropical Storm Daniel was located near latitude 15.3 north...longitude 135.1 west. That's about 1,350 miles (2, 175 km) east of Hilo, Hawaii. It is moving west near 16 mph (26 kmh) and is expected to keep moving in that direction over the next couple of days. Daniel is expected to weaken to tropical depression status by July 11.

On July 10 at 5 a.m. EDT, Emilia's maximum sustained winds were near 140 mph (220 kmh). By 11 a.m. EDT, Emilia's maximum sustained winds dropped to 130 mph (215 kmh) and was still holding onto Category 4 hurricane status. Emilia was located about 685 miles (1100 km) south-southwest of the southern tip of Baja California. Emilia is moving at 10 mph (17 kmh) to the west-northwest.

System 98E is slowly coming together, and has a 40 percent chance of becoming a tropical depression in the next day or two.

Text Credit: Rob Gutro
NASA's Goddard Space Flight CenterGreenbelt, Md.



July 9, 2012

3-D view of Daniel shows that very little rainfall was present in the western side and that most of Daniel's structure was at lower levels.› View larger image
TRMM's Precipitation Radar (PR) data show a 3-D view of Daniel (looking from the west). This view shows that very little rainfall was present in the western side. This image also shows that most of Daniels structure was at lower levels. A few of the most powerful storms in the eastern side of Daniel's eye wall reached to heights of about 11km (~6.8 miles).
Credit: SSAI/NASA, Hal Pierce
Hurricane Daniel on July 9, 2012 at 0913 UTC when Daniel had started to weaken.› View larger image
Hurricane Daniel was seen by the TRMM satellite on July 9, 2012 at 0913 UTC ( 2:13 AM PDT). Daniel had started to weaken. Rainfall data from TRMM's Microwave Imager and Precipitation Radar instruments show that only light to moderate rainfall was contained in Daniel's rain bands.
Credit: SSAI/NASA, Hal Pierce
NASA's Terra satellite captured this visible image of Hurricane Daniel in the eastern Pacific on July 8, 2012 at 1920 UTC 3:20 p.m.› View larger image
NASA's Terra satellite captured this visible image of Hurricane Daniel in the eastern Pacific on July 8, 2012 at 1920 UTC 3:20 p.m. EDT.
Credit: NASA MODIS Rapid Response Team
MODIS captured this visible image of Emilia when it was a tropical storm off the western coast of Mexico on July 8.› View larger image
NASA's Terra satellite captured this visible image of Emilia when it was a tropical storm off the western coast of Mexico on July 8, 2012 at 1745 UTC 1:45 p.m. EDT.
Credit: NASA MODIS Rapid Response Team
This TRMM image of rainfall rates in Tropical Storm Emilia was captured on July 8, before she became a hurricane.› View larger image
This TRMM image of rainfall rates in Tropical Storm Emilia was captured on July 8, before she became a hurricane. The heavy rain (in red) was falling at a rate of more than 2 inches/50 mm per hour.
Credit: SSAI/NASA, Hal Pierce
NASA Analyzes Twin Hurricanes in the Eastern Pacific

There are two hurricanes in the Eastern Pacific today, Daniel and Emilia. NASA's TRMM satellite passed over both storms in pinpointed the intensity of the rainfall within each storm, indicative of their power. Emilia is dropping rain at a greater rate than Daniel according to satellite data.

Tropical storm Daniel strengthened and became the third hurricane over the weekend, and today, Monday, July 9, Tropical Storm Emilia strengthened into the fourth hurricane of the season. Tropical storm Emilia formed on July 7 as tropical depression 5E and became a tropical storm on July 8. On July 9, Emilia is trailing Daniel by 645 miles in the eastern Pacific, as both storms continue to move away from land.

The Tropical Rainfall Measuring Mission (TRMM) satellite recently saw both tropical cyclones. TRMM flew above hurricane Daniel on July 8, 2012 at 0019 UTC (July 7, 2012 5:19 p.m. PDT) and over Emilia when it was a tropical storm on July 8, 2012 at 0837 UTC (1:37 a.m. PDT). Rainfall data collected with TRMM's Microwave Imager (TMI) and Precipitation Radar (PR) instruments was overlaid on enhanced infrared and visible images from TRMM's Visible and InfraRed Scanner (VIRS) at NASA's Goddard Space Flight Center in Greenbelt, Md. to show the intensity of the rain falling within each storm.

TRMM noticed only light-to-moderate rainfall happening within Daniel, as the hurricane continues to weaken. Light-to-moderate rainfall means rain is falling between 20 and 40 millimeters (.78 to 1.57 inches) per hour.

When TRMM passed over Tropical Storm Emilia on July 8, before she became a hurricane, data showed various areas of heavy rainfall in bands of thunderstorms along the northwestern, north, and eastern quadrants, feeding into the center. The heavy rain was falling at a rate of more than 2 inches/50 mm per hour. Surrounding the areas of heavy rain were large areas of light-to-moderate rainfall between 20 and 40 millimeters (.78 to 1.57 inches) per hour.

NASA's Terra satellite also passed over both storms, providing a clear, visible image of the cloud cover and extent on July 8. At that time, compact Daniel had a visible eye, while Emilia did not, and was still getting organized.

The Moderate Resolution Imaging Spectroradiometer (MODIS) instrument onboard NASA's Terra satellite captured a visible image of Hurricane Daniel in the eastern Pacific on July 8, 2012 at 1920 UTC 3:20 p.m. EDT that showed the tight circulation of the storm, and a small cloud-filled eye.

On July 9, Hurricane Daniel had maximum sustained winds near 85 mph (140 kmh). The center of Daniel was about 1355 miles (2185 km) west-southwest of the southern tip of Baja California, near latitude 15.3 north and longitude 129.1 west. The National Hurricane Center reports that "Daniel is moving toward the west near 15 mph (24 kmh) and this general motion with a slight increase in forward speed is expected during the next couple of days. Slow weakening is forecast during the next 48 hours."

Hurricane-force winds only extend out 25 miles (35 km) from the center, and tropical storm-force winds extend out up to 115 miles (185 km), making Daniel about 230 miles in diameter.

NASA's Terra satellite captured a visible image of Emilia when it was a tropical storm off the western coast of Mexico on July 8, 2012 at 1745 UTC 1:45 p.m. EDT. The storm appeared comma-shaped, but there was no visible eye in the center of circulation.

Emilia underwent rapid intensification today, July 9, from a tropical storm in the morning hours (Pacific Daylight Time/local time) into a category two hurricane. Emilia's maximum sustained winds were near 100 mph (160 kmh) and the National Hurricane Center noted that she could become a major hurricane (Category Three) later today. Emilia was located about 710 miles (1145 km) south of the southern tip of Baja California. Emilia is moving at 12 mph (19 kmh) to the west-northwest.

Just like Daniel, Emilia's hurricane force winds extend outward up to 25 miles (35 km) from the center of circulation, but Emilia's tropical-storm-force winds are much smaller in area, extending to 80 miles (130 km). Size doesn't matter here, though, because Emilia is expected to become a major hurricane in the next day, while Daniel weakens.

Text Credit: Rob Gutro / Hal Pierce
NASA's Goddard Space Flight Center / SSAI, Greenbelt, Md.





















TRMM Reveals the Rainfall Under Tropical Storm Daniel's Clouds


Click here to see an animation showing a blend between infrared and visible imagery of Tropical Storm Daniel on July 6, 2012. Both images were taken from NASA's Tropical Rainfall Measuring Mission's (TRMM) Visible and InfraRed Scanner (VIRS) and the same image with TRMM rainfall overlaid. Credit: SSAI/NASA, Hal Pierce




July 6, 2012

rainfall measurements of Daniel › View larger image
The TRMM satellite passed over Tropical Storm Daniel on July 6, 2012 at 0034 UTC and data revealed heavy rain falling around the southern periphery of the center of circulation. The heavy rain (in red) was falling at a rate of more than 2 inches/50 mm per hour. The yellow, green and blue areas indicate light-to-moderate rainfall between 20 and 40 millimeters (.78 to 1.57 inches) per hour.
Credit: SSAI/NASA, Hal Pierce
NASA's TRMM Satellite Sees Heavy Rainfall in Tropical Storm Daniel's Center

NASA's TRMM satellite revealed that Tropical Storm Daniel's most concentrated rainfall is occurring around the storm's center.

When the Tropical Rainfall Measuring Mission (TRMM) satellite passed over Tropical Storm Daniel on July 6, 2012 at 0034 UTC, data revealed heavy rain falling around the southern periphery of the center of circulation. The heavy rain was falling at a rate of more than 2 inches/50 mm per hour. TRMM is jointly managed by both NASA and the Japanese Space Agency, JAXA.

Daniel remains no threat to land, however, as the storm is expected to continue on a westward track into the open waters of the eastern Pacific over the weekend.

At 5 a.m. EDT (2 a.m. PDT) on Friday, July 6, 2012, Daniel was far from land. Its center was located about 640 miles (1030 kilometers) south-southwest of the southern tip of Baja California, near 14.6 North and 114.2 West. Daniel's maximum sustained winds increased to 65 mph (100 kmh) and the tropical storm is moving west at 14 mph (22 kmh). The National Hurricane Center expects Daniel to continue moving in this direction over the weekend.

Text Credit: Rob Gutro
NASA's Goddard Space Flight Center, Greenbelt, Md.



July 5, 2012

On July 4, TRMM saw strong convective storms dropping heavy rainfall near the tropical depression's center of circulation.› View larger image
When TRMM passed over TD 4E on July 4, 2012, it saw strong convective storms were dropping heavy rainfall (red) near the center of the tropical depression's center of circulation. That rain was falling at a rate of more than 2 inches/50 mm per hour. TRMM's Precipitation Radar (PR) instrument found that a few of these towering storms reached heights of about 15 km (~9.3 miles).
Credit: SSAI/NASA, Hal Pierce
NASA Sees Tropical Fireworks in E. Pacific in Newborn Tropical Storm Daniel

Tropical "fireworks" happened in the eastern Pacific Ocean on July 4 as Tropical Depression 04E formed off western Mexico's coast and strengthened into Tropical Storm Daniel. NASA's Tropical Rainfall Measuring Mission (TRMM) satellite captured an image of TD 4E's rainfall and towering clouds as it passed overhead, and saw "hot towers" that suggested it would become a tropical storm.

The TRMM satellite got a very good look at recently formed Tropical Depression 4E (TD 4E) at 1040 UTC (6:40 a.m. EDT) on July 4, 2012. The hot towering cumulonimbus clouds called "hot towers" shooting up like a roman candle around the center of circulation provide the fireworks for the depression.

A "hot tower" is a rain cloud that reaches at least to the top of the troposphere, the lowest layer of the atmosphere. It extends approximately nine miles (14.5 km) high in the tropics. These towers are called "hot" because they rise to such altitude due to the large amount of latent heat. Water vapor releases this latent heat as it condenses into liquid.

Research by Owen Kelley and John Stout of George Mason University and NASA's Goddard Space Flight Center, Greenbelt, Md., shows that a tropical cyclone with a hot tower in its eyewall was twice as likely to intensify within the next six hours than a cyclone that lacked a tower and Tropical Depression 4E became Daniel by 11 a.m. EDT on July 5.

When TRMM passed over TD 4E, rainfall data from TRMM's Microwave Imager (TMI) and Precipitation Radar (PR) instruments revealed that strong convective storms were dropping heavy rainfall near the center of the tropical depression's center of circulation. TRMM's Precipitation Radar (PR) instrument found that a few of these towering storms reached heights of about 15 km (~9.3 miles). TRMM PR also found that rainfall within TD 4E was returning reflectivity values of over 51.5 dBZ. Those data provided additional proof that heavy rainfall was occurring within TD 4E.

At 5 p.m. EDT on July 4, the depression has maximum winds near 35 mph/55 kmh, and is about 445 miles (715 km) south-southwest of Manzanillo, Mexico. That's near 13.5 North and 107.8 West. It was moving to the west-northwest at 13 mph/20 kmh and headed away from land and out to sea.

At 11 a.m. EDT (8 a.m. PDT) on July 5, 2012, Tropical Depression 4E became Tropical Storm Danie with maximum sustained winds now near 45 mph (75 kmh). It was located near latitude 14.2 north and longitude 110.5 west. That's about 600 miles (970 km) south of the southern tip of Baja California. Daniel is moving toward the west-northwest near 12 mph (19 kmh). That general motion is forecast to continue, followed by a turn to the west, according to the National Hurricane Center.

Text Credit: Rob Gutro / Hal Pierce
NASA Goddard Space Flight Center / SSAI, Greenbelt, Md.