July 1, 2010
Satellite Shows Areas Of Alex’s Heavy Rainfall
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 was created on July 1 at 1200 UTC (8 a.m. EDT) from TRMM data which 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.
Image Caption: 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: NASA/SSAI, Hal Pierce
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