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Hurricane Season 2010: Hurricane Alex (Atlantic Ocean)
07.13.10
 
July 13, 2010

The life of Hurricane Alex as he struggled across hurricane alley for two weeks in June 2010View Video
The life of Hurricane Alex as he struggled across hurricane alley for two weeks in June 2010, as seen by the GOES-13 satellite.
Credit: NASA/GOES Project
Although Alex's center in the southwestern Gulf of Mexico, his cloud cover extends over a large area of the Gulf.> View larger image
The GOES-13 satellite captured this visible image of Tropical Storm Alex on June 29 at 1732 UTC (1:32 p.m. EDT). Although Alex's center in the southwestern Gulf of Mexico, his cloud cover extends over a large area of the Gulf.
Credit: NASA/GOES Project
NASA Releases GOES-13 Satellite Movie of the Life and Times of Hurricane Alex

NASA's GOES Project has just released a "movie" of satellite imagery showing the life and times of 2010's only June hurricane. From birth to death, the GOES-13 satellite kept an eye on the life and times of Hurricane Alex for two weeks in June, 2010.

Hurricane Alex struggled for life for two weeks in June 2010, and the Geostationary Operational Environmental Satellite (GOES) known as GOES-13 captured satellite images of the storm. Those satellite images were compiled into an animation by Dr. Dennis Chesters of NASA's GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Md. "The animation is an example of one of the tropical-storm-in-ten which bloom into a hurricane," Chesters said.

GOES-13 is operated by the National Oceanic and Atmospheric Administration, and images are created by NASA's GOES Project, located at NASA's Goddard Space Flight Center, Greenbelt, Md.

Satellites like GOES-13 provide a great research tool for forecasters by showing where and how a tropical depression forms and where it tracks during its brief lifetime. GOES-13 captured Alex from its birth on Friday, June 25 at 6 p.m. EDT when "System 93L" developed into the first tropical depression of the Atlantic Ocean hurricane season. At 5 a.m. EDT on Saturday, June 26 that Tropical Depression One strengthened into a tropical storm and was named Alex. Tropical Storm Alex intensified by 11 p.m. EDT on June 29 and became the first hurricane of the 2010 Atlantic Ocean Hurricane Season.

Alex made landfall at 10 p.m. EDT in northeastern Mexico, about 110 miles south of Brownsville, Texas. By 8 a.m. EDT on July 1, Alex has weakened to a tropical storm and GOES satellite imagery showed it moving near the high mountains of Mexico. GOES-13 satellite imagery followed Alex's remnants as they moved inland over northeastern Mexico and southern Texas in the days following.

The first Atlantic Ocean basin hurricane of the season proved fatal to at least 30 people. Alex's heavy rainfall flooded towns, created mudslides, caused waterways to overflow and broke records.

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



July 7, 2010

MISR views of Hurricane Alex on June 30, 2010› View larger image
Figure 1: The Multi-angle Imaging SpectroRadiometer instrument on NASA's Terra spacecraft captured these two views of Hurricane Alex on June 30, 2010. The vertical-viewing camera image at left is paired with a map of Alex's cloud top heights at right.
Credit: NASA/GSFC/LaRC/JPL, MISR Team
3-D MISR view of Hurricane Alex on June 30, 2010› View larger image
Figure 2: This stereo anaglyph was created from MISR's nadir and 26-degree forward-viewing cameras and is displayed at four times finer spatial resolution than Figure 1.
Credit: NASA/GSFC/LaRC/JPL, MISR Team
Hurricane Alex Disrupts Gulf Cleanup

These views of Hurricane Alex in the western Gulf of Mexico were acquired by the Multi-angle Imaging SpectroRadiometer (MISR) instrument aboard NASA's Terra satellite just after noon Central Daylight Time on June 30, 2010. Around this time NOAA's National Hurricane Center reported Alex to be a strengthening Category 1 hurricane with maximum sustained winds of 135 kilometers per hour (84 miles per hour). By 6 p.m. Central time, Alex had been upgraded to Category 2, with maximum sustained winds of 155 kilometers per hour (nearly 100 miles per hour). The storm made landfall in northeastern Mexico, just south of the Texas border, about three hours later. High winds and rough seas further north in the Gulf halted cleanup efforts associated with the Deepwater Horizon oil spill.

The two panels in Figure 1 shows a nadir (vertical-viewing) camera image of the hurricane on the left, and a map of cloud-top heights on the right. The heights are derived using automated stereo processing of the imagery from cameras pointed at different view angles. North is at the top. Each panel covers an area about 376 kilometers (234 miles) wide by 986 kilometers (613 miles) long. The height contrast between the clouds in the lower part of the atmosphere and the high clouds surrounding the hurricane's eye is dramatically seen in Figure 2, which is a stereo anaglyph of a portion of the scene, created from MISR's nadir and 26-degree forward-viewing cameras, and displayed at four times finer spatial resolution than Figure 1. In this image, north is at the left. Viewing with red/blue glasses (red filter over left eye) is required to obtain the 3-D effect. The dimensions of this image are 455 by 325 kilometers (283 by 202 miles).

MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Science Mission Directorate, Washington, D.C. The Terra spacecraft is managed by NASA's Goddard Space Flight Center, Greenbelt, Md. The MISR data were obtained from the NASA Langley Research Center Atmospheric Science Data Center in Hampton, Va. JPL is a division of the California Institute of Technology.

Image credit: NASA/GSFC/LaRC/JPL, MISR Team

Text credit: Alan Buis, NASA's Jet Propulsion Laboratory



July 6, 2010

These are TRMM rainmap totals from June 26 to July 2.> View larger image
These are TRMM rainmap totals from June 26 to July 2. The black line marks Alex's path. Moderate (green) to heavy rain amounts (orange/red) fell offshore over the western Gulf of Mexico. The heaviest amounts were just south of Louisiana where ~8 to 12 inches rain fell (orange/ dark red). Highest rainfall over land were over the northern Yucatan Peninsula and range from ~4 to 8 inches (green and orange).
Credit: NASA/SSAI, Hal Pierce
NASA's TRMM Satellite Mapped Hurricane Alex's Excessive Rainfall

The Tropical Rainfall Measuring Mission satellite known as TRMM provides estimates of rainfall from space, and was very busy during Hurricane Alex's lifetime in June.

According to the National Hurricane Center, Hurricane Alex made landfall in northeast Mexico around 9 pm CDT Wednesday evening on the 30th of June 2010 near the Mexican municipality of Soto la Marina as a category 2 storm. Although Alex weakened and was downgraded to a tropical storm the next morning as it tracked westward across central Mexico, the effects of the storm were continuing to be felt in the form of heavy rain and flooding.

TRMM is managed by both NASA and the Japanese Space Agency, JAXA. The TRMM satellite was launched back in November of 1997 with the primary mission of measuring rainfall from space using both passive microwave and active radar sensors. The TRMM-based, near-real time Multi-satellite Precipitation Analysis (TMPA) at the NASA Goddard Space Flight Center, Greenbelt, Md. provides estimates of rainfall over the global tropics. TMPA rainfall totals were obtained and calculated from the time when Alex first became a tropical depression in the western Caribbean to the present, 26 June to 2 July 2010. The data shows Alex's path with appropriate storms symbols marking the 00 and 12Z positions and intensity. Most of the moderate to heavy rain amounts fell offshore over the western Gulf of Mexico.

The rain in the central and southwestern Gulf are directly associated with Alex, while the rain across the northern Gulf was enhanced by the storm's counter-clock-wise circulation drawing moist air into the northern Gulf. The heaviest amounts were just south of Louisiana where from 200 to over 300 mm of rain fell (~8 to 12 inches).

The highest rainfall totals over land for the period are located over the northern Yucatan Peninsula north of where Alex made its first landfall in Belize and range from 100 to over 200 mm (~4 to 8 inches). So far Alex has dumped from 50 to over 100 mm of rain (~2 to 4 inches) over northeastern Mexico, resulting in two fatalities. In addition to the flooding over land, winds and heavy seas from Alex have hampered efforts to clean up the oil spill in the Gulf of Mexico.

To see an animation of Hurricane Alex's precipitation as it moved through the Gulf of Mexico, go to: http://trmm.gsfc.nasa.gov/trmm_rain/Events/alex_26june-2july10_rain.mov

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



July 2, 2010

GOES-13 visible satellite imagery from July 2 shows Hurricane Alex remnants › View larger image
GOES-13 visible satellite imagery from July 2 at 1331 UTC (9:31 a.m. EDT) shows a lingering stationary front straddling Texas and the Gulf Coast. The front is apparent in the clouds that stretch from Texas (left) where Alex's remnants are located, east over the Gulf of Mexico in a wavy pattern that extends east of Florida (right) and into the Atlantic Ocean.
Credit: NASA GOES Project
Alex's Aftermath Brings Flash Flood Watches to Texas

Tropical Depression Alex dissipated over the mountains of central Mexico, but his rainy remnants have moved into south, central and western Texas. The GOES-13 satellite is keeping an eye on Alex's remnants as they have prompted flash flood watches in those areas today.

The latest imagery from the Geostationary Operational Environmental Satellite, GOES-13, revealed Alex's remnants over Texas, and showed a lingering stationary front straddling Texas and the Gulf Coast. The front is apparent in the clouds that stretch from Texas where Alex's remnants are located, east over the Gulf of Mexico in a wavy pattern that extends east of Florida and into the Atlantic Ocean. As the front gradually moves north and dissipates through the Independence Day weekend, it will trigger thunderstorms along the boundary, which could bring heavy rainfall.

GOES-13 is operated by the National Oceanic and Atmospheric Administration, and images are created by NASA's GOES Project, located at NASA's Goddard Space Flight Center, Greenbelt, Md.

After a hurricane or tropical storm makes landfall and moves inland, the potential for heavy rainfall continues. Alex is no exception. The National Weather Service notes today, July 2 that "Tropical moisture associated with the remnants of Alex will continue to lift northwestward from northern Mexico and south Texas through Saturday." Because many locations across west Texas and southeast New Mexico have already received moderate to heavy rainfall over the past few days, the additional rainfall is causing the potential for flooding and flash flooding through Saturday.

A Flash Flood Watch has been issued from the early morning of July 2 through Saturday, July 3 for all of southern and central Texas from east to west and for southeastern New Mexico. Major metropolitan areas within that watch that will experience heavy rainfall include Houston, Dallas, San Antonio, Victoria, Austin, Corpus Christi, Midland and Lubbock.

On July 1, Corpus Christi had received 2.75 inches of rain and Victoria, Texas broke a record for the day with 2.79 inches of rainfall. Both areas remain under flood watches today as 2 to 4 inches more rainfall is possible, with isolated amounts to 5 inches.

The National Hurricane Center issued their final bulletin on Tropical Depression Alex on July 1 at 11 p.m. EDT. At that time, Alex's winds were down to 30 mph, and it was moving west at 12 mph. Alex was near 23.3 North and 102.4 West, about 35 miles north-northeast of Zacatecas, Mexico.

Hurricane Alex made landfall around 10 p.m. EDT at the village of Soto La Marina, about 100 miles south of Brownsville, Texas. Alex caused power outages and floods that have reportedly killed two people in northern Mexico. The states of Tamaulipas and Nuevo Leon reported high winds, heavy rains, flooding and power outages. Alex brought rains and gusty winds to southern Texas as it came ashore in Mexico and even spawned several tornadoes in Brownsville.

Over the next couple of days Texas will experience the rainfall from Alex's remnants, as the low pressure center tracks north into western Oklahoma and Kansas, where computer models expect it to dissipate early next week.

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



July 1, 2010

NASA TRMM Satellite Data Shows Areas of Alex's Heavy Rainfall

This flood map was created on July 1 at 1200 UTC (8 a.m. EDT) from TRMM data, and shows estimated rainfall from Hurricane Alex. The red areas indicate as much as 10 inches of rainfall, while the yellow areas indicate up to 5 inches. The heaviest rainfall is apparent in northeastern Mexico. › View larger image
This flood map was created on July 1 at 1200 UTC (8 a.m. EDT) from TRMM data, and shows estimated rainfall from Hurricane Alex. The red areas indicate as much as 10 inches of rainfall, while the yellow areas indicate up to 5 inches. The heaviest rainfall is apparent in northeastern Mexico.
Credit: Credit: NASA/SSAI, Hal Pierce
Areas of northeastern Mexico were slammed with heavy rainfall, and NASA's Tropical Rainfall Measuring Mission Satellite estimated more than 10 inches of rainfall fell in various locations and that data was used to create a rainfall map.

Heavy rain amounts from satellites and flood inundation calculations from a hydrological computer model are updated every three hours globally with the results shown on the "Global Flood and Landslide Monitoring" area of NASA's Tropical Rainfall Measuring Mission (TRMM) web page.

A flood map created on July 1 at 1200 UTC (8 a.m. EDT) from TRMM data, and shows estimated rainfall from Hurricane Alex. The map is color coded where red areas indicate as much as 10 inches of rainfall, while the yellow areas indicate up to 5 inches. The heaviest rainfall appeared in northeastern Mexico on the latest flood map.

The TRMM Microwave Imager (TMI) showed that ALEX had a well defined eye containing powerful thunderstorms that were dropping extreme amounts of rain as it was making landfall. The analysis indicates that an area in southeastern Texas, that was away from the center of the hurricane, had the most intense rainfall with rain rates over 36 mm/hr (~1.41 inches/hour).

For an animation that shows flood potential (yellow and red areas over land) from Hurricane Alex created by Hal Pierce of NASA's TRMM Satellite Team at NASA's Goddard Space Flight Center, Greenbelt, Md., go to: http://trmm.gsfc.nasa.gov/trmm_rain/Events/alex_23june-1july_flood_potential.mov. Hurricane's Celia and Darby were spinning in the eastern Pacific at the same time Alex developed and are also seen here.

At 11 a.m. EDT, Tropical Storm Alex had maximum sustained winds near 50 mph, but was weakening. The National Hurricane Center expects that Alex will likely dissipate over the high terrain of Mexico overnight.

Alex was producing very heavy rain over Mexico and south Texas at 11 a.m. EDT today, and continues to weaken. At that time, the center was located near latitude 23.1 north and longitude 100.3 west. That places Alex's center about 150 miles east of Zacatecas, Mexico. Alex is moving toward the west near 13 mph and this motion is expected to continue today. Estimated minimum central pressure is 985 millibars.

The National Hurricane Center noted that Alex is expected to produce additional rainfall accumulations of 2 to 4 inches over portions of southern Texas with possible isolated maximum storm-total amounts around 10 inches. There is a possibility of isolated tornadoes over portions of extreme southern Texas today. Meanwhile, additional rainfalls of 6 to 12 inches are expected over northeastern Mexico, with isolated totals of 20 inches.

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





This video of satellite imagery from the GOES-13 satellite shows Hurricane Alex's track from the Western Gulf of Mexico through landfall in northeastern Mexico in the early morning hours of July 1 and after landfall. The video runs from June 29 at 1140 UTC (7:40 a.m. EDT) to July 1 at 1215 UTC (8:15 a.m. EDT).
Credit: NASA GOES Project


GOES-13 Satellite Catches Alex as a Tropical Storm Now, After a Landfall in Northeastern Mexico

Alex made landfall at 10 p.m. EDT in northeastern Mexico, about 110 miles south of Brownsville, Texas. By 8 a.m. EDT on July 1, Alex has weakened to a tropical storm and GOES satellite imagery showed it moving near the high mountains of Mexico.

At 8 a.m. EDT on July 1, Alex was about 55 miles (85 km) west of Ciudad Victoria, Mexico. That's near 23.8 North and 99.8 West. Its maximum sustained winds were now around 70 mph (110 km/hr) with higher gusts. Alex is moving west at 12 mph (19 km/hr) and has a minimum central pressure of 977 millibars. The Geostationary Operational Environmental Satellite that covers the U.S. east coast, called GOES-13 captured an image of Alex moving into the Mexican mountains at 1131 UTC (7:31 a.m. EDT).

GOES satellite imagery is created by NASA's GOES Project, located at NASA's Goddard Space Flight Center, Greenbelt, Md. GOES-13 is operated by the National Oceanic and Atmospheric Administration.

The government of Mexico has replaced the hurricane warning with a Tropical storm warning for the coast of Mexico from Rio San Fernando to La Cruz.

NASA's AIRS instrument aboard the Aqua satellite captured Alex on June 30 at 2017 UTC (4:17 p.m. EDT) about 6 hours before Alex's eye made landfall. At that time, the strongest thunderstorms were mostly still offshore and the infrared imagery showed that cloud tops were so high they were colder than -63 Fahrenheit.

NASA's AIRS instrument aboard the Aqua satellite captured Alex about 6 hours before Alex's eye made landfall › View larger image
NASA's AIRS instrument aboard the Aqua satellite captured Alex on June 30 at 2017 UTC (4:17 p.m. EDT) about 6 hours before Alex's eye made landfall. The strongest thunderstorms were mostly still offshore at this time (purple) where cloud tops were so high they were colder than -63 Fahrenheit.
Credit: NASA JPL, Ed Olsen
When Alex did make landfall, it was packing maximum sustained winds near 97 mph (85 knots) and dumped 8 to 12 inches of rain on northeastern states in Mexico. The National Hurricane Center in Miami, Fla. noted that Alex will continue to be a big rainmaker. Alex is expected to produce total rainfall accumulations of 6 to 12 inches over portions of northeastern Mexico. Isolated maximum amounts of 20 inches are possible over the higher elevations of northeastern Mexico. Alex is expected to produce total rainfall accumulations of 4 to 8 inches over portions of southern Texas, with possible isolated maximum amounts around 10 inches.

In Texas, Galveston and Jamaica Beach, Texas received enough rainfall to cover the roadways last night, but the roads have already cleared this morning. Brownsville, Texas reports no wind damage, no power outages, and clear roadways. Sporadic power outages, a wind gust to 66 mph, and a storm surge of 3.44 feet were reported in South Padre Island, Texas. In Boca Chica, Texas, there was a report of a tornado touchdown at 6:45 p.m. CDT.

The system is now moving inland and weakening. Heavy rainfall is the main threat as Alex continues to weaken. Alex is expected to weaken to a tropical depression later today and dissipate in the next 24 to 36 hours.

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



June 30, 2010


Alex was near the western coast of Mexico's Yucatan Peninsula when again seen by NASA's TRMM satellite on June 27 at 6:14 p.m. EDT. TRMM looks underneath of the storm's clouds to reveal the underlying rain structure. This animation shows the light rain (0.25 inches) in blue, medium rain (0.5 inches) in green, heavier rain (25 mm or 1 inch per hour) in yellow and extremely heavy rain in red (50 mm or 2 inches per hour). Credit: NASA GSFC SVS, Lori Perkins


NASA's TRMM Satellite Sees Heavy Rainfall in Hurricane Alex

Hurricane Alex is generating some very heavy rainfall, and the Tropical Rainfall Measuring Mission satellite known as TRMM has been calculating it from its orbit in space.

As predicted by the National Hurricane Center (NHC) in Miami, Florida, Alex intensified after entering the warm waters of the southwest Gulf of Mexico.

At NASA's Goddard Space Flight Center in Greenbelt, Md., scientists created an analysis of Alex's rainfall using data captured by the TRMM satellite on June 29, 2010 at 1350 UTC (9:50 a.m. EDT). At that time the sustained winds around Alex were estimated to be 60 knots (~69 mph). Alex continued to strengthen and was classified as a hurricane early on 30 June 2010. This made Alex the first hurricane in the 2010 Atlantic hurricane season.

The rainfall analysis used TRMM Precipitation Radar (PR) data and TRMM Microwave Imager (TMI) data. The TMI data showed that a heavy band of precipitation (some areas showed rain falling at more than 2 inches per hour) was spiraling into the center of Alex's intensifying circulation. The precipitation analysis was overlaid on visible and infrared data from TRMM's Visible Infrared Scanner (VIRS). In this image a Geostationary Operational Environmental Satellite (GOES East) visible image was used to fill in locations not viewed by the TRMM satellite.

The TRMM satellite captured heavy rain spiraling toward Hurricane Alex's center › View larger image
The TRMM satellite's data on June 29, 2010 at 9:50 a.m. EDT showed some heavy rain (red) falling at up to 2 inches per hour, spiraling toward Hurricane Alex's center. The yellow and green areas indicate moderate rainfall between .78 to 1.57 inches per hour.
Credit: NASA, Hal Pierce
Alex is expected to continue to be a large rainmaker when it makes landfall. Rainfall accumulations are expected of between 6 and 12 inches, with isolated amounts of 20 inches.

Tropical Storm-force winds are expected to reach coastal areas in the warning areas this afternoon, while hurricane-force winds will reach the coast tonight. In addition, the National Hurricane Center noted "a dangerous storm surge will raise water levels by as much as 3 to 5 feet above ground level along the immediate coast to the north of where the center makes landfall."

By 11 a.m. EDT, Alex was still a category one hurricane with maximum sustained winds near 80 mph. Alex was located about 145 miles (235 km) east of La Pesca, Mexico and 190 miles (310 km) southeast of Brownsville, Texas. That makes Alex's center near 23.8 North and 95.5 West. Alex is moving northwest at 7 mph (11 km/hr), and has a minimum central pressure near 961 millibars.

Satellite data show that Alex is a large hurricane and the hurricane force winds extend outward up to 60 miles (95 km) from the center. Tropical storm force winds extend outward up to 200 miles (325 km) primarily to the northeast of the center.

The National Hurricane Center noted today that "Given such a low minimum pressure...the current satellite presentation and a favorable environment for intensification...the winds should increase today and Alex could reach category two before landfall."

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



Visible image of Alex › Larger image
This visible image of Alex was captured by the Aqua satellite on June 29 at 3:35 p.m. EDT as it churned over the Gulf of Mexico.
Credit: NASA MODIS Rapid Response Team
Alex Now a Hurricane, May Continue to Strengthen

Tropical Storm Alex intensified by 11 p.m. EDT on June 29 and became the first hurricane of the 2010 Atlantic Ocean Hurricane Season. NASA satellites continue to provide visible, infrared and microwave satellite data to forecasters to help the National Hurricane Center forecast Alex's intensity and track, and NASA's Aqua satellite flew over Alex hours before it became a hurricane yesterday.

The Moderate Resolution Imaging Spectroradiometer (MODIS) instrument that flies aboard NASA's Aqua satellite is one of those NASA instruments that provide forecasters data. MODIS captured a visible image of Alex on June 29 at 3:35 p.m. EDT as it churned over the Gulf of Mexico, and provided a high resolution image of this large storm's extent in the Gulf of Mexico.

Now that Alex has become a hurricane, the storm has the title of being the first June hurricane in the Atlantic Ocean since 1995.

A hurricane warning is in effect for the coast of Texas south of Baffin Bay to the mouth of the Rio Grande and the coast of Mexico from the mouth of the Rio Grande to La Cruz. A tropical storm warning is in effect for the coast of Texas from Baffin Bay to Port Oconnor, and the coast of Mexico south of La Cruz To Cabo Rojo.

At 8 a.m. EDT, Hurricane Alex's center was closing in on the Mexican and south Texas coasts. Alex's center was located about 155 miles (250 km) east of La Pesca, Mexico and 220 miles (355 km) southeast of Brownsville, Texas. That puts Alex's center near latitude 23.4 north and longitude 95.3 west. Alex is moving toward the west-northwest near 7 mph. The National Hurricane Center calls for a "A slow west to west-northwestward motion over the next 24 to 48 hours."

The Hurricane Center forecast says that on the forecast track the center of Alex will approach the coast of northeastern Mexico or southern Texas by late this afternoon or early evening, and Alex will make landfall in the hurricane warning area late tonight or early Thursday morning.

Maximum sustained winds remain near 80 mph so Alex is a category one hurricane on the Saffir-Simpson Hurricane wind scale. Additional strengthening is forecast and Alex could become a category two hurricane prior to landfall.

The National Oceanic and Atmospheric Administration's buoy 42055 located southeast of Alex recently reported sustained winds of 54 mph with a gust of 63 mph.

Smaller hurricanes have higher pressures, and larger hurricanes tend to have lower pressures. Alex is a very large hurricane and has a minimum central pressure near 959 millibars. Hurricane force winds extend outward up to 25 miles from the center and tropical storm force winds extend outward up to 200 miles. Flood watches stretch from New Orleans to southern Texas because of the size of Hurricane Alex.

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



June 29, 2010

Infrared image of Tropical Storm Alex› Larger image
This infrared image of Tropical Storm Alex from the AIRS instrument on NASA's Aqua satellite, depicts the temperatures of the storm's cloud tops. The coldest clouds and heaviest precipitation are shown in purples and blues.
Credit: NASA/JPL-Caltech
Alex Stirs Up the Gulf

Tropical Storm Alex, the first storm of the 2010 Atlantic hurricane season, continues to pick up steam as it crosses the western Gulf of Mexico.

According to NOAA's National Hurricane Center, Alex is expected to approach the coast of northeast Mexico and southern Texas on Wed., June 30, and make landfall Wednesday night. The storm is expected to reach a peak intensity of 80 to 85 knots (92 to 98 miles per hour) before landfall, which would make it either a strong Category One or weak Category Two hurricane. Alex's tropical storm-force winds currently extend outward up to 175 miles (280 kilometers) from its center. The storm is expected to produce total rainfall accumulations of 15 to 30 centimeters (6 to 12 inches) over parts of northeastern Mexico and southern Texas, with isolated amounts up to 51 centimeters (20 inches). A storm surge of about 1 to 1.5 meters (3 to 5 feet) above ground level is forecast along the immediate coast near and to the north of where Alex makes landfall.

The JPL-built and- managed Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua satellite captured this infrared image of Tropical Storm Alex at 3:29 p.m. EDT (19:29 UTC) on June 29, 2010. The AIRS data create an accurate 3-D map of atmospheric temperature, water vapor and clouds, all of which are helpful to forecasters. The image shows the temperature of Alex's cloud tops or the surface of Earth in cloud-free regions. The coldest cloud-top temperatures appear in purple, indicating towering cold clouds and heavy precipitation. The infrared signal of AIRS does not penetrate through clouds. Where there are no clouds, AIRS reads the infrared signal from the surface of the ocean waters, revealing warmer temperatures in orange and red.

For more information on AIRS, visit: http://airs.jpl.nasa.gov/. For more information on NASA's research of hurricanes/tropical cyclones, visit: http://www.nasa.gov/mission_pages/hurricanes/main/index.html.

Text Credit: Alan Buis 818-354-0474
Jet Propulsion Laboratory, Pasadena, Calif.
Alan.buis@jpl.nasa.gov



The GOES-13 satellite captured this visible image of Tropical Storm Alex on June 29 › View larger image
The GOES-13 satellite captured this visible image of Tropical Storm Alex on June 29 at 1732 UTC (1:32 p.m. EDT). Although Alex's center in the southwestern Gulf of Mexico, his cloud cover extends over a large area of the Gulf.
Credit: NASA GOES Project
NASA Data Sees Alex's Core Aligned, Growing Toward Hurricane Strength

Two instruments aboard NASA's Aqua satellite have provided some critical information to hurricane forecasters about tropical storm Alex as it threatens the northern Mexico and southern Texas coasts. Data from those two instruments were used in the National Hurricane Center's forecast at 8 a.m. EDT today, June 29 as they provided information on Alex's structure, direction, cloud top temperatures and convection.

As Alex nears hurricane strength at 8 a.m. EDT on June 29, a Hurricane Warning is in effect for the coast of Texas south of Baffin Bay to the mouth of the Rio Grande and the coast of Mexico from the mouth of the Rio Grande to La Cruz. A tropical storm warning in effect for the coast of Texas From Baffin Bay to Port O'Connor. The weather is already deteriorating today in the northern Mexico/southern Texas coast. Alex's clouds are already visible from the southern Texas coast this morning.

A hurricane warning means that hurricane conditions are expected somewhere within the warning area. A warning is typically issued 36 hours before the anticipated first occurrence of Tropical-storm-force winds. A tropical storm warning means that tropical storm conditions are expected somewhere within the warning area within 36 hours.

At 2 p.m. EDT the center of Tropical Storm Alex was located near latitude 22.9 north and longitude 93.6 west. That's about 270 miles (435 km) east-southeast of La Pesca, Mexico, and 320 miles (515 km) southeast of Brownsville, Texas. Alex is now moving toward the northwest near 13 mph (21 km/hr). Maximum sustained winds are near 70 mph (110 km/hr) with higher gusts. The National Hurricane Center notes that "Additional strengthening is forecast during the next 48 hours and Alex is likely to become a hurricane later today."

A turn toward the northwest is expected later today, followed by a gradual turn toward the west-northwest on Wednesday. The minimum central pressure just reported by the hurricane hunter is 981 millibars, a drop of 2 millibars from three hours before. That drop in pressure indicates a strengthening storm.

Tropical storm force winds extend outward up to 140 miles (220 km), that's 35 miles greater than at 11 a.m. EDT today, so the storm is growing. An automated weather station managed by the Mexican Navy at Cayo Arenas reported a wind gust of 68 mph (109 km/hr) in mid-morning hours of June 29.

The Atmospheric Infrared Sounder (AIRS) instrument reads the temperature of thunderstorm cloud tops in tropical cyclones and the sea surface temperatures around them. The colder temperatures of cloud tops, the higher they are in the atmosphere, and the stronger they are. Very high, cold cloud tops can be colder than -63 Fahrenheit, and likely dump heavy rainfall.

AIRS data noticed increasing deep convection (rapidly rising air that form clouds and thunderstorms that power the tropical cyclone)in the eastern semicircle of Alex's small developing eye indicating a strengthening storm.

The AIRS instrument works with another instrument on NASA's Aqua satellite to provide more insight on the workings of tropical cyclones. AIRS data combined with data from the Advanced Microwave Sounding Unit (AMSU) helps pinpoint the motion of tropical cyclones. AIRS/AMSU data confirmed that Alex's initial motion in the last 8 hours is 340 or north-northwest.

Microwave data from AMSU at 0243 UTC (June 28 at 10:43 p.m. EDT) and imagery captured at 0114 UTC (9:14 p.m. EDT, June 28) from the Special Sensor Microwave/Imager (SSM/I) instrument that flies on the U.S. Air Force Defense Meteorological Satellite Program (DMSP) indicated a small mid-level eye feature very near the low-level recon center position. The AMSU data indicated that Alex's center of circulation has aligned vertically, which favors steady intensification because there is low wind shear and warm ocean surface temperatures.

So, what is AMSU and what does it do? The Advanced Microwave Sounding Unit is a multi-channel microwave radiometer installed on NASA's Aqua satellite and meteorological satellites such as the on several NOAA low-Earth satellites. The instrument examines several bands of microwave radiation from the atmosphere to perform atmospheric sounding (reading) of temperature and moisture levels. AMSU data is used extensively in weather prediction. Temperature data are processed as quickly as possible and sent to numerical weather prediction (NWP) centers around the world. This data helps keep the assessment of the current state of the atmosphere correct, which in turn helps make forecasts more accurate.

What are the hazards that Alex will bring to Northeastern Mexico and southeastern Texas? Heavy rainfall, gusty winds and storm surge. Accumulations of 6 to 12 inches of rainfall over portions of northeastern Mexico and southern Texas are possible, with isolated amounts to as much as 20 inches. This extreme rainfall can cause flash-flooding and life-threatening mud slides. Additional rainfall accumulations of 2 to 4 inches are possible over portions of southern Mexico through today.

Alex is expected to strengthen into hurricane, and tropical storms conditions are expected to reach coastal areas on Wednesday. In addition, the National Hurricane Center warns "a dangerous storm surge will raise water levels by as much as 3 to 5 feet above ground level along the immediate coast near and to the north of where the center makes landfall. The surge could penetrate inland as far as several miles from the shore with depth generally decreasing as the water moves inland. Near the coast...the surge will be accompanied by large and destructive waves."

What is expected to turn Alex to the west-northwest? A building sub-tropical ridge (that's an area of high pressure) to the north and east of Alex over the next 3 days which is expected to gradually steer the cyclone on a west-northwestward or westward track with time. The National Hurricane Center noted that Alex is now moving northwestward and shift west-northwest on Wednesday. Alex is expected to make landfall in northern Mexico or southern Texas late Wednesday night.

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



June 28, 2010

NASA's AIRS infrared imagery on June 26 (left) and 27 (right) show  tropical storm Alex's areas of high, cold, thunderstorm cloud tops. › View larger image
NASA's AIRS infrared imagery on June 26 (left) and 27 (right) showed areas of high, cold, thunderstorm cloud tops (colder than -63F) and the warm western Caribbean waters. On June 26, Alex dropped very heavy rainfall on Honduras, Belize and Guatemala. On June 27 AIRS showed the largest concentration of thunderstorms over the Yucatan Peninsula.
Credit: NASA JPL, Ed Olsen
The MODIS instrument on NASA's Aqua satellite captures tropical storm Alex over the Yucatan Peninsula › View larger image
The visible image of Alex on the left was taken from the MODIS instrument on June 26 at 19:05 UTC from NASA's Aqua satellite. The image on the right is from the MODIS instrument on the Terra satellite, captured June 27 at 16:40 UTC when Alex was over the Yucatan Peninsula.
Credit: NASA Goddard / MODIS Rapid Response Team
Tropical Storm Alex Now in Gulf of Mexico, Brought Heavy Rainfall to Belize, Yucatan

NASA's infrared satellite imagery captured high, cold, strong thunderstorms within Tropical Storm Alex over the past weekend and they are still creating heavy rainfall. Alex's center is now moving out into the southwestern Gulf of Mexico and departing the Yucatan Peninsula. Alex is moving into warm waters and is expected to strengthen into a hurricane in the next day.

Today, June 28, a tropical storm warning is in effect for the coast of Belize and the east coast of the Yucatan Peninsula of Mexico from Chetumal to Cancun.

NASA's Atmospheric Infrared Sounder (AIRS) instrument aboard the Aqua satellite captured infrared imagery on June 26 and 27 that showed the areas of high, cold, thunderstorm cloud tops and the warm western Caribbean waters.

On June 26 at 1800 UTC (2 p.m. EDT) AIRS infrared imagery showed a large concentration of powerful thunderstorms around Alex's center while it dropped very heavy rainfall on Honduras, Belize and Guatemala.

On June 27 at 2 a.m. EDT, AIRS imagery showed the largest concentration of thunderstorms over the Yucatan Peninsula. The AIRS instrument also senses the heat from the warm sea surface of the Caribbean and the Gulf of Mexico and showed that those temperatures were as warm as or warmer than the 80 degree Fahrenheit threshold needed to power tropical cyclones.

ALEX'S HISTORY

On Friday, June 25 at 6 p.m. EDT, System 93L developed into the first tropical depression of the Atlantic Ocean hurricane season. By 8 p.m. EDT on the 25, Tropical Depression One was nearing tropical storm strength, so a tropical storm warning was issued for Belize. Three hours later, Tropical Depression One was still moving west-northwestward toward Belize and the Yucatan. At 11:25 p.m. EDT, Tropical Storm Watches went up for Honduras.

It wasn't until 5 a.m. EDT on Saturday, June 26 that Tropical Depression One strengthened into a tropical storm and was named Alex. By 2 p.m. EDT that day, Alex was a large tropical storm and still moving toward Belize and the Yucatan. Three hours later that day and Air Force plane noted that Alex had strengthened and weather in Belize and the Yucatan was deteriorating rapidly. By 7 p.m. EDT, Alex was near the Belize coast and it was dumping heavy rainfall in northern Guatemala and the Yucatan Peninsula. By 10 p.m. EDT on June 26, Alex was making landfall over Belize, some 20 miles (20 km) northwest of Belize City with maximum sustained winds near 60 mph.

By 5 a.m. EDT on Monday, June 28, the National Hurricane Center noted that Alex is now getting better organized and is pulling away from the Yucatan Peninsula. Alex is about 75 miles (115 km) west of Campeche, Mexico; 440 miles (710 km) east-southeast of Tampico, Mexico, near 19.7 North and 91.6 West. Maximum sustained winds at that time were near 50 mph and minimum central pressure was 990 millibars.

Rainfall is the largest threat from Alex, as the storm is expected to produce total rain accumulations of 4 to 8 inches over the Yucatan Peninsula, southern Mexico and portions of Guatemala through Tuesday. Isolated maximum amounts of 15 inches are possible over mountainous areas. These rains could cause life-threatening flash floods and mudslides.

At 8 a.m. EDT, Hurricane Hunter aircraft reported sustained winds inside the storm near 66 mph, and a minimum central pressure near 989 millibars. Alex is also in an environmental area that will help Alex strengthen over the next several days as it heads north into the western Gulf of Mexico. Tropical Storm watches maybe required later today for coastal areas of northeastern Mexico and south Texas.

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



TRMM capture rainfall from tropical storm Alex. › View larger image
This time series of rainfall occurring in Alex shows light to moderate rainfall (blue and green) on June 26 at 10:59 am, and by 7:10 pm, Alex dumped moderate to heavy rainfall (red) on Mexico's Yucatan Peninsula, Belize and northeastern Guatemala. Rainfall on June 27 appears light to moderate (blue) as Alex moves north into the Gulf.
Credit: NASA/SSAI, Hal Pierce
TRMM Satellite Catches Tropical Storm Alex's Rains Enter the Gulf of Mexico

The Tropical Rainfall Measuring Mission, or TRMM satellite has the ability to measure rainfall from space, and has kept tabs on rain intensity in Tropical Storm Alex over the past weekend.

TRMM measured the heaviest rainfall from Alex late on June 26 when moderate to heavy rainfall fell on Mexico's Yucatan Peninsula, Belize and northeastern Guatemala.

The TRMM satellite, managed by both NASA and the Japanese Space Agency JAXA showed that late in the day on June 27, rains from Alex were already falling in the southwestern Gulf of Mexico. When the TRMM satellite flew over Alex on June 27 at 2213 UTC (6:13 p.m. EDT), Alex was a tropical depression near the western coast of Mexico's Yucatan Peninsula. At that time, Alex had weakened and wasn't dropping the very heavy rainfall that had occurred a day earlier causing deadly flooding.

On June 26, TRMM captured Alex's rainfall when the center of the storm was very close to the northern coast of Belize on June 26 at 2310 UTC (7:10 p.m. EDT). The rainfall analysis from TRMM's Precipitation Radar (PR) instrument and TRMM's Microwave Imager (TMI) data showed that Alex was pounding Mexico's Yucatan Peninsula, Belize and northeastern Guatemala with moderate to heavy rainfall with a few areas having totals of over 50mm/hr (~2 inches).

TRMM had passed over Alex earlier on that same day, at 1459 UTC (10:59 a.m. EDT) when Alex was upgraded to a Tropical Storm. At that time ALex was located near 17.3 north latitude 86.1 west longitude. Data from TRMM Precipitation Radar (PR) and the TRMM Microwave Imager (TMI) instruments were used in the rainfall analysis of the storm. TRMM showed that Alex was producing light to moderate rainfall over the eastern Yucatan with moderate to heavy rainfall falling along the coasts of Belize and northwestern Honduras.

Tropical Storm Alex is now entering the Gulf of Mexico and is a very large storm. The National Hurricane Center in Miami, Fla. is forecasting Alex to increase to hurricane strength in the next three days while moving toward the west-northwest over the warm waters of the southwest Gulf of Mexico.

For more TRMM imagery of Tropical Storm Alex, visit the TRMM mission web site: trmm.gsfc.nasa.gov

Text Credit: Hal Pierce, SSAI/NASA's Goddard Space Flight Center



June 25, 2010

GOES-13 captured a visible image of System 93L › View larger image
GOES-13 captured a visible image on June 25 at 10:45 a.m. EDT of System 93L (large area of clouds far left) in the western Caribbean Sea which may become Alex and a second area of cloudiness and showers (far right) east of the Leeward Islands that forecasters are watching for tropical development.
Credit: NASA GOES Project
Expecting Alex in the Caribbean

Forecasters on June 25 had given System 93L in the western Caribbean an 80 percent chance of developing into Tropical Depression Alex, and weekends seem to always birth tropical depressions. The GOES-13 satellite captured a visible image of both System 93L and a second low east of the Leeward Islands that has a much lesser chance of development this weekend.

The Geostationary Operational Environmental Satellite called GOES-13 captured a visible image of System 93L and the second area of cloudiness and showers east of the Leewards in a satellite image on June 25 at 14:45 UTC (10:45 a.m. EDT). The satellite image was created by NASA's GOES Project, located at NASA's Goddard Space Flight Center, Greenbelt, Md. GOES-13 is operated by the National Oceanic and Atmospheric Administration.

System 93L has become better organized today and upper-level winds are becoming more conducive for development, so tropical depression Alex will likely form later today or Saturday.

System 93L has gusty winds and heavy rainfall, which will move slowly west-northwest and reach the Yucatan Peninsula this weekend. For weekend forecast updates on 93L (or Alex), visit the National Hurricane Center web site at: www.nhc.noaa.gov.

The second area that forecasters are watching this weekend is in the eastern Caribbean, east of the Leeward Islands. It's a disorganized area of clouds and showers that is associated with a tropical wave that's interacting with an upper-level trough. A trough is an elongated area of low pressure (and this one is in the upper level of the troposphere).

The National Hurricane Center only gives this system a 20 percent chance of development into a tropical depression over the next 48 hours. The low is moving northwest between 10 and 15 mph.

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