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Hurricane Season 2011: Tropical Storm Arlene (Atlantic Ocean/Caribbean Sea)
07.06.11
 
MODIS view of northeastern Mexico on July 5, 2011; the large number of dark blue areas inland represent flooding. › View larger image
The impact of Arlene’s heavy rain in northeastern Mexico was clear in early July as the MODIS instrument on NASA’s Aqua satellite passed overhead on July 5, 2011. The large number of dark blue areas inland represent flooding.
Credit: NASA/Earth Observatory/MODIS Rapid Response
MODIS view of northeastern Mexico on June 19, 2011 does not have those dark blue areas that are visible on July 5 › View larger image
This image of northeastern Mexico on June 19, 2011 does not have those dark blue areas that are visible in the July 5, 2011 image, indicating where the floods happened from Tropical Storm Arlene.
Credit: NASA/Earth Observatory/MODIS Rapid Response
NASA's Aqua Satellite Spots Flooding from Tropical Storm Arlene in Mexico

On June 30, 2011, Tropical Storm Arlene made landfall near Cabo Rojo in Veracruz, Mexico. As the storm came ashore, the U.S. National Weather Service forecast total rainfall accumulations up to 8 inches (20 centimeters), and warned of potentially life-threatening flash floods and mudslides.

The impact of Arlene’s heavy rain was clear in early July as the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite passed overhead. MODIS captured an image on July 5, 2011 after Arlene had passed through.

The image was created using a combination of visible and infrared light to increase contrast between water and land. In the image, water varies from electric blue to navy. Depending on land cover, areas above water range in color from green to brown. Clouds are pale to medium blue-green.

A network of lakes extends inland from the city of Tampico. In the image from July 5, the lake network appears to have multiplied, with standing water covering large areas northwest and southwest of the city. Standing water is also apparent south of Cabo Rojo.

On July 5, 2011, the Associated Press reported that the Mexican government had raised the official death toll for Arlene to 22. Deaths occurred in multiple states, with the most deaths reported in Hidalgo.

Arlene was the first named Atlantic storm of the season.

Text credit:Michon Scott, NASA's Earth Observatory/NASA's Goddard Space Flight Center, Greenbelt, Md.









July 5, 2011

TRMM ainfall totals exceed 100 to 150 mm of rainover most of the central east coast of Mexico. › View larger image
The solid black line in the image shows the path of Arlene with storms symbols marking the 00 and 12 Zulu Time (8 a.m. EDT) positions and intensity. Most of the heaviest rain occurs offshore and along the coast. Over land, rainfall totals exceed 100 to 150 mm of rain (~4 to 6 inches, shown in green) over most of the central east coast of Mexico. In the vicinity of where Arlene made landfall, there are higher amounts in excess of 250 mm (~10 inches, shown in orange).
Credit: NASA/SSAI, Hal Pierce
NASA's TRMM Satellite Measures Tropical Storm Arlene's Heavy Rains in Mexico

Arlene formed into a tropical storm on the evening of June 28, 2011 in the Bay of Campeche in the southwestern Gulf of Mexico from an area of low pressure that had formed the day before just west of the Yucatan Peninsula.

Arlene did not have time to fully develop and came ashore as a strong tropical storm two days later on the morning of June 30 near Cabo Rojo along Mexico's east coast with sustained winds reported at 65 mph.

Although wind damage from the storm was relatively minor, Arlene brings the threat of heavy rains and flash flooding to the region as it continues to move inland. The Tropical Rainfall Measuring Mission (or TRMM) satellite has proven to be a useful platform for measuring rainfall from tropical cyclones, including typhoons and hurricanes.

Launched in 1997, TRMM uses a combination of passive microwave and active radar sensors to measure rainfall from space. For increased coverage, TRMM can be used to calibrate rainfall estimates from additional satellites. The TRMM-based, near-real time Multi-satellite Precipitation Analysis (TMPA) at the NASA Goddard Space Flight Center provides estimates of rainfall over the global Tropics. TMPA rainfall totals were created for the period June 24 to July 1, 2011 for the southwestern Gulf of Mexico and the surrounding region.

The solid black line in the image shows the path of Arlene with storms symbols marking the 00 and 12 Zulu Time (8 a.m. EDT) positions and intensity. Most of the heaviest rain occurs offshore and along the coast. Over land, TMPA rainfall totals exceed 100 to 150 mm of rain (~4 to 6 inches, shown in green) over most of the central east coast of Mexico. In the vicinity of where Arlene made landfall, there are higher amounts in excess of 250 mm (~10 inches, shown in orange).

In addition to the rain from Arlene, a passing tropical wave contributed to the rainfall totals over the Yucatan prior to Arlene's formation. Although the rainfall totals drop off quickly inland. As Arlene continues to trek westward it will continue to bring the threat of heavy rain and potential flooding to central Mexico. Arlene is expected to eventually dissipate over the mountains of central Mexico. So far two fatalities are being blamed on the storm. Much of Mexico has been in a severe drought recently, so Arlene's rains have been a welcome site.

TRMM is a joint mission between NASA and the Japanese space agency JAXA.

Text credit:Steve Lang, SSAI/NASA's Goddard Space Flight Center, Greenbelt, Md.



July 1, 2011

satellite image of Arlene › View larger image
This TRMM rainfall map indicates that between 100-300 millimeters (mm) of rain (4-8 inches) of rain have recently fallen in northeastern Mexico, mostly from Tropical Storm Arlene. The yellow-green area on the rainfall map is around 100 mm, red is between 300-400 mm.
Credit: NASA/SSAI, Hal Pierce
satellite image of Arlene › View larger image
This image from the TRMM satellite shows rainfall accumulation from 8 p.m. (EDT) on June 27 to 5 p.m. June 30 EDT from Tropical Storm Arlene. Arlene was in the process of making landfall on June 30 south of Tampico near Cabo Rojo, Mexico. The heaviest rainfall was along the coast (yellow) that measured 150 mm (almost 6 inches). As of July 1, only a light amount of rain from Arlene had fallen in far southern Texas, as the storm rained out over the mountains of Mexico.
Credit: NASA/Jim Acker
TRMM Satellite Measures Tropical Storm Arlene's Soaking Rains in Mexico

On Friday, July 1, the remnants of the once tropical storm Arlene are dissipating over the north central mountains of Mexico. Arlene formed on June 29 and made landfall in northeastern Mexico on June 30, dropping a great amount of rainfall that was captured in a NASA satellite-generated rainfall map.

NASA's Tropical Rainfall Measuring Mission (TRMM) satellite provides rainfall data from its perch in orbit above the Earth. TRMM has been called a "rain gauge in space" and can provide accurate measurements of rainfall in tropical and sub-tropical areas around the world.

TRMM rainfall data from June 25 to July 1 was used to create a rainfall total map (of tropics around the world) that indentified rainfall from Tropical Storm Arlene. The rainmap showed that as much as 12 inches (300 mm) of rain fell in northeastern Mexico from Arlene. TRMM showed rainfall totals of 4 to 8 inches (10 to 20 mm) over the eastern states of Veracruz, Tamaulipas, and eastern part of San Luis Potosi.

The TRMM rainmap was created in the Laboratory for Atmospheres at NASA's Goddard Space Flight Center, Greenbelt, Md. by the TRMM precipitation research team.

At 11 p.m. EDT on June 30, the National Hurricane Center noted that Arlene's center had dissipated over the Sierra Madre Mountains of Mexico. At that time it was located near 20.9 North and 99.1 West. That's about 110 miles (175 km) west of Tuxpan, Mexico. Its sustained winds were near 30 mph and it was still moving to the west-southwest near 8 mph (13 kmh).

By Friday morning (EDT) on July 1, Arlene's remnants were still moving over central Mexico, generating several additional inches of rainfall. Residents in north central and northeastern Mexico should still be on guard for heavy rainfall, flash flooding and mudslides.

Moisture from the Gulf of Mexico was still streaming into northeastern Mexico, following Arlene. It was generating a large area of showers and thunderstorms that could be seen on live radar from the National Weather Service in Brownsville, Texas as of 11 a.m. EDT. For the Brownsville radar, visit:http://radar.weather.gov/radar.php?rid=BRO&product=NCR&overlay=11101111&loop=yes. To see the rains also in north central Mexico from Arlene's remnants, visit the National Weather Service radar loop from San Antonio, Texas: http://radar.weather.gov/radar.php?product=NCR&rid=dfx&loop=yes.

For more information about how TRMM looks at rainfall, visit NASA's TRMM website at: http://trmm.gsfc.nasa.gov/. TRMM is a joint mission between NASA and the Japanese space agency JAXA. For more information about the history of Tropical Storm Arlene, visit NASA's Hurricane page at: www.nasa.gov/hurricane.

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



June 30, 2011

Storm center is shown with a red tropical storm symbol; red areas are heavy rainfall (2 inches/50 mm per hour). › View larger image
When TRMM again flew over tropical storm Arlene on June 30, 2011 at 0408 UTC (12:08 a.m. EDT) it was just beginning to make landfall in northeastern Mexico near Cabo Rojo. Storm center is shown with a red tropical storm symbol. The yellow and green areas indicate moderate rainfall between .78 to 1.57 inches (20 to 40 mm) per hour. Red areas are heavy rainfall (2 inches/50 mm per hour).
Credit: NASA/SSAI, Hal Pierce
NASA's TRMM Satellite Eyes Heavy Rainfall in Tropical Storm Arlene

NASA's Tropical Rainfall Measuring Mission measured some heavy rainfall in Tropical Storm Arlene as it was coming ashore into Mexico early today. That heavy rainfall moved with the storm, soaking northeastern Mexico.

When TRMM again flew over tropical storm Arlene on June 30, 2011 at 0408 UTC (12:08 a.m. EDT) it was just beginning to make landfall in northeastern Mexico near Cabo Rojo.

Arlene had become a strong tropical storm with sustained winds of about 55 knots (~63 mph). TRMM's Microwave Imager (TMI) and Precipitation Radar (PR) data were used to create a rainfall analysis. That analysis showed that Arlene contained areas of very heavy rainfall, with areas showing rainfall at about 2 inches (50 mm) per hour.

At the time of the image, a few rain showers from Arlene were starting to reach Mexico and extreme southern Texas but the most intense storms were still located east of Mexico's coast.

TRMM images are complicated to create, using different data from TRMM instruments. In order to get a complete look at Arlene, Hal Pierce of NASA's TRMM team at the NASA Goddard Space Flight Center in Greenbelt, Md. also included an infrared image from the GOES-EAST satellite (received at about the same time) to fill in areas not viewed by the TRMM satellite.

By 2 p.m. EDT on June 30, Arlene weakened as she continued tracking inland. Her maximum sustained winds were near 50 mph (80 kmh), and she was moving west near 7 mph (11 kmh). Arlene was centered about 55 miles south-southwest of Tampico, Mexico near 21.5 North and 98.1 West. Minimum central pressure was 997 millibars.

The National Hurricane Center forecast indicates that Arlene is expected to move west to west-southwest over the next day and a half. Arlene is expected to dissipate over the mountains of central Mexico by Friday or Friday night.

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



GOES-13 captured Tropical Storm Arlene on June 30, 2011 as it was inland and just west of Cabo Rojo, Mexico. › View larger image
The GOES-13 satellite captured this image of Tropical Storm Arlene at 1431 UTC (10:31 a.m. EDT) on June 30, 2011 as it was inland and just west of Cabo Rojo, Mexico.
Credit: NASA/NOAA GOES Project
GOES-13 movie of Tropical Storm Arlene in 15 minute intervals from June 28 at 1415 to June 30. › View GOES-13 movie
This movie of GOES-13 satellite imagery of Tropical Storm Arlene in 15 minute intervals from June 28 at 1415 (10:15 a.m. EDT) to the same time on June 30, shows the storm making landfall in northeastern Mexico near Cabo Rojo.
Credit: NASA/NOAA GOES Project, Dennis Chesters
Tropical Storm Arlene Moves Inland Over Mexico: A GOES-13 Satellite Movie View

Tropical Storm Arlene made landfall early today and is making its way through northeastern Mexico today as the GOES-13 satellite continues to track its movement. A movie from today's GOES satellite data shows Arlene making that landfall and moving inland.

Tropical Storm Arlene never made to hurricane strength, but did become a strong tropical storm with maximum sustained winds near 65 mph. To be classified hurricane strength maximum winds need to be 74 mph or greater. As a strong tropical storm, Arlene is creating a lot of problems with very heavy rainfall causing flash flooding and mudslides in mountainous areas. Arlene is dropping between 4 and 8 inches of rain as it tracks through northern Mexico with isolated amounts up to 15 inches falling in mountainous areas.

Arlene made landfall near Cabo Rojo in northeastern Mexico this morning, June 30 at 7 a.m. EDT. It continues to move west through northern Mexico. By 11 a.m. EDT, Arlene's center was just west of Cabo Rojo as it tracks slowly to the west at 7 mph (11 kmh). It was centered near 21.6 North and 97.7 West. That's about 45 miles north-northwest of Tuxpan and the same distance from Tampico, although south-southeast of that city. Minimum central pressure is 994 millibars.

GOES-13 is one of several satellites keeping track of Tropical Storm Arlene. Because GOES-13 monitors the eastern U.S. and the Atlantic, and Arlene is moving west, the GOES-11 satellite is going to pick up watching Arlene's movements. GOES-11 monitors the western U.S. and the eastern Pacific Ocean.

Both GOES-13 and GOES-11 are operated by NOAA. NASA's GOES Project creates images and animations from both satellites, and used the continuous data from GOES-13 to make a two-day movie showing Arlene's landfall today. NASA's GOES Project works out of the NASA Goddard Space Flight Center in Greenbelt, Md.

The animation shows Arlene from June 28 at 1415 (10:15 a.m. EDT) to June 30 at 1415. In those two days, the circulation of Arlene became more apparent as the center moved away from the Yucatan Peninsula and into the southwestern Gulf of Mexico. Satellite imagery also showed that eastern side of the storm contained more cloud cover when it was over open ocean.

The National Hurricane Center noted that the center of Arlene should continue moving inland over mainland Mexico today and will likely dissipate over the central Mexico mountains sometime on Friday, July 1.

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



June 29, 2011

Some of the heaviest rainfall was in feeder bands over land along the southwestern Gulf of Mexico. › View larger image
The TRMM satellite captured rainfall within tropical storm Arlene on June29, 2011 at 0000 UTC (7 p.m. CDT) as it was getting better organized and contained scattered heavy thunderstorms dropping rain at a rate of over 50 mm/hr (~2 inches). Some of the heaviest rainfall was not near the center of Arlene's circulation but was in feeder bands over l and along the southwestern Gulf of Mexico. The yellow and green areas indicate moderate rainfall between .78 to 1.57 inches (20 to 40 mm) per hour.
Credit: NASA/SSAI, Hal Pierce
A 3-D analysis of Arlene revealed very powerful thunderstorms in a feeder band over the southeastern Yucatan Peninsula. › View larger image
A 3-D analysis of Arlene's vertical structure using TRMM precipitation radar revealed that very powerful thunderstorms in a feeder band over the southeastern Yucatan Peninsula reached to heights of 17 km (~10.6 miles) on June 29, 2011. The yellow and green areas indicate moderate rainfall between .78 to 1.57 inches (20 to 40 mm) per hour. Red areas indicate heavy rainfall of 2 inches/50 mm per hour.
Credit: NASA/SSAI, Hal Pierce
Most of Arlene's heaviest thunderstorms (purple) were over the waters of the Gulf of Mexico. › View larger image
NASA's Aqua satellite passed over Tropical Storm Arlene on June 29, 2011 at 08:05 UTC (4:05 a.m. EDT). Most of Arlene's heaviest thunderstorms (purple) were over the waters of the Gulf of Mexico.
Credit: NASA/JPL, Ed Olsen
NASA Satellites See Strong Thunderstorms, Heavy Rain as Arlene Nears Landfall

Two different NASA satellites provided valuable information about the hundreds of thunderstorms that make up Tropical Storm Arlene as it nears landfall in northeastern Mexico. NASA's Aqua satellite measured cloud top temperatures giving clues about the strength of storms, while the TRMM satellite measured rainfall rates and cloud heights. All of this data is useful to forecasters in predicting Arlene's next moves.

The Tropical Rainfall Measuring Mission (TRMM) satellite had a good look at Arlene when it passed above on June 29, 2011 at 0502 UTC (0:02 AM CDT). At that time Arlene's winds were estimated to be about 34 knots (~39 mph) indicating that it was barely a tropical storm.

TRMM's Microwave Imager (TMI) and Precipitation Radar (PR) data showed that Arlene was getting better organized and contained scattered heavy thunderstorms dropping rain at a rate of over 50 mm/hr (~2 inches). Some of the heaviest rainfall was not near the center of Arlene's circulation but was in feeder bands over land along the southwestern Gulf of Mexico. A 3-D analysis of Arlene's vertical structure using TRMM PR revealed that very powerful thunderstorms in a feeder band over the southeastern Yucatan Peninsula reached to heights of 17 km (~10.6 miles).

NASA's Aqua satellite passed over Tropical Storm Arlene on June 29, 2011 at 08:05 UTC (4:05 a.m. EDT). At that time, the Atmospheric Infrared Sounder (AIRS) instrument showed that most of Arlene's heaviest thunderstorms and coldest cloud top temperatures (-63F/-52C) were over the waters of the Gulf of Mexico. That data matched with the TRMM data that showed the heaviest rainfall was over open water.

At 1 p.m. EDT on June 29, Arlene's maximum sustained winds had increased to 50 mph (85 kmh). It was located just 95 miles (155 km) east of Tuxpan, Mexico and 150 miles east-southeast of Tampico. That put Arlene's center near 21.1 North and 95.9 West. It was moving west near 8 mph (13 kmh) and had a minimum central pressure of 1000 millibars. A hurricane watch is in effect for the coast of eastern Mexico from Barra De Nautla Northward to La Cruz and a tropical storm watch extends farther along the coast. For updates, visit: www.nhc.noaa.gov.

Residents in the area of the watches should prepare for gusty winds, heavy rainfall and rough surf.

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
























This image of Arlene taken from the GOES-13 on June 29 shows the storm just off the northeastern coast of Mexico. › View larger image
This visible image of Arlene was taken from the GOES-13 satellite on June 29 at 11:31 UTC (7:30 a.m. EDT) and shows the storm just off the northeastern coast of Mexico.
Credit: NASA/NOAA GOES Project, Dennis Chesters
GOES-13 shows Arlene developing from a low pressure area called System 95L off Mexico's northeastern coastline. › View GOES-13 movie
GOES-13 satellite imagery in 15 minute intervals from June 27 at 7:15 a.m. EDT until June 28 at 7:15 a.m. EDT shows Arlene developing from a low pressure area called System 95L off Mexico's northeastern coastline.
Credit: NASA/NOAA GOES Project, Dennis Chesters
NASA/NOAA GOES-13 Satellite Movie Shows How Tropical Storm Arlene Formed!

Have you ever seen a low pressure area develop into a full-fledged tropical storm? The GOES-13 satellite has and now you can see it in a new animation released today from NASA and NOAA.

System 95L strengthened and became the Atlantic Ocean hurricane season's first tropical storm, named Arlene. It happened at 8 p.m. EDT on June 27 in the southwestern Gulf of Mexico, and the GOES-13 satellite caught the storm coming together.

The Geostationary Operational Environmental Satellite called GOES-13 provides continuous visible and infrared imagery of the eastern U.S. and Atlantic Ocean basin from its position in space. GOES satellites are operated by NOAA, and the NASA GOES Project located at NASA's Goddard Space Flight Center in Greenbelt, Md. creates images and compiled them into the video of the storm as it developed from June 27 to June 28.

The animation includes sped-up infrared and visible frames of data from the GOES-13 satellite and is squeezed down to 25 seconds. The movie shows satellite imagery that was captured in 15 minute intervals from June 27 at 11:15 UTC (7:15 a.m. EDT/6:15 a.m. CDT) until June 28 at 1115 UTC (7:15 a.m. EDT/6:15 a.m. CDT) taking the viewer from the time Arlene was the low pressure area called System 95L to the time she formed off of Mexico's northeastern coastline.

On June 27 when the animation begins at 1115 UTC, it's difficult to pinpoint a center of circulation for System 95L as it was over the Yucatan Peninsula. As the animation goes on, by 1931 UTC (3:31 p.m. EDT) you can start to see the circulation, and the middle of the storm becomes apparent as it moved into the southwestern Gulf of Mexico where it strengthened.

Arlene formed at 8 p.m. EDT on June 28 in the southwestern Gulf of Mexico after it crossed the Yucatan Peninsula as a low pressure system, previously known as System 95L. At that time, its maximum sustained winds were near 40 mph (65 kmh) and it was about 240 miles (380 km) east of Tuxpan, Mexico near 21.2 North and 93.7 West.

Twelve hours later at 8 a.m. EDT on June 28, its sustained winds remained at 40 mph, and it had moved closer to the Mexican coast. Arlene was located about 17 miles (280 km) east of Tampico, Mexico near 21.8 North and 9.2 West. It was moving to the west-northwest near 8 mph (13 kmh) and had a minimum central pressure of 1002 millibars.

Watches and warnings are in effect for northeastern Mexico today as Arlene creeps closer to a landfall in that country. A tropical storm warning is in effect from Barra De Nautla north to Bahia Algodones. Tropical Storm conditions are expected within 24 hours (from 8 a.m. EDT) in that area.

NOAA's National Hurricane Center (NHC) noted that Arlene is expected to produce copious amounts of rainfall between 4 to 8 inches and as much as 15 inches in mountainous areas, which could cause flash flooding and mudslides. Winds are expected to be at tropical storm strength along the coastline, and as Arlene moves inland those winds are expected to weaken. Coastal areas also need to heed a storm surge that could raise water levels by 1 to 2 feet above normal, according to the NHC.

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



June 28, 2011

GOES-13 captured an image of System 95L; Cuba is seen to the right, and the U.S. Gulf coast is north (top). › View larger image
GOES-13 captured an image of the clouds associated with the low called System 95L on June 28 at 1345 UTC (9:35 a.m. EDT) over the Yucatan Peninsula. Cuba is seen to the right, and the U.S. Gulf coast is north (top).
Credit: NASA/NOAA GOES Project
A Possible Developing Tropical Depression Seen by the GOES-13 Satellite

A low pressure system over the Bay of Campeche in the southwestern Caribbean appears to be getting organized on satellite imagery.

A visible image taken at 9:35 a.m. EDT from the Geostationary Operational Environmental Satellite, GOES-13 today, June 28, shows a large area of cloudiness over the Yucatan Peninsula. Those clouds contain moderate to scattered strong convection (thunderstorms), some of which have heavy rainfall.

GOES satellites are operated by NOAA, and this image was created by the NASA/NOAA GOES Project, located at NASA's Goddard Space Flight Center, Greenbelt, Md.

At 8 a.m. EDT on June 28, System 95L was located near 20 degrees North and 93 degrees West. It was just east of a tropical wave that runs along 94 West and 95 West. System 95L has a minimum central pressure of 1007 millibars. It is moving to the west-northwest at 5 to 10 mph.

Forecasters at the National Hurricane Center note that "Upper-level winds are forecast to gradually become more conducive for development during the next couple of days." So they've given this low a medium chance (50 percent) of becoming a tropical cyclone during the next 48 hours.

If System 95L strengthens over the warm waters of the Gulf of Mexico once the upper level winds ease and allow it to consolidate, and it becomes a tropical storm, it would get the name Arlene.

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