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Hurricane Season 2010: Tropical Storm Tasha (South Pacific Ocean)
01.03.11
 
January 3, 2011

Cyclone Tasha Adds to Severe Flooding Over Eastern Australia

TRMM captured this image of Tasha at 15:32 UTC (5:32 am AEST) on the 24th of December 2010 just before it became a Category 1 cyclone. › View larger image
TRMM captured this image of Tasha at 15:32 UTC (5:32 am AEST) on the 24th of December 2010 just before it became a Category 1 cyclone. Tasha appears as an area of enhanced rainfall with moderate (green areas) to localized areas of heavy rain (red areas) embedded within a broader area of light to moderate rain (blue and green areas, respectively) draped along the coast of northeastern Australia.
Credit: SSAI/NASA Goddard, Hal Pierce
TRMM rainfall totals are shown here for the period December 1 to 29, 2010 for northeastern Australia and the surrounding region. › View larger image
TRMM rainfall totals are shown here for the period December 1 to 29, 2010 for northeastern Australia and the surrounding region. Rainfall totals for the period exceed 300 mm (~12 inches) all along the northeast and northern coasts. Farther inland amounts drop off but still exceed 100 to 200 mm (~4 to 8 inches) over much of Queensland.
Credit: SSAI/NASA Goddard, Hal Pierce
Although Tasha is responsible for dumping a lot of the rain over a short period, eastern Australia had already been experiencing above normal rainfall. › View larger image
Although Tasha is responsible for dumping a lot of the rain (note the storm track indicated by the symbols) over a short period (the Bureau had a report of up to 10 inches in 24 hours as a result of Tasha), eastern Australia had already been experiencing above normal rainfall as result of above normal ocean temperatures in the West Pacific due to La Nina. TMPA rainfall anomalies for the month of December 2010 for the tropical Pacific and surrounding region were constructed by first computing the average rainfall rate over the period and then subtracting the 10-year average rate for the same period.
Credit: SSAI/NASA Goddard, Hal Pierce
Cyclone Tasha recently made landfall just south of Cairns along the northeast coast of Queensland, Australia during the early morning hours on Christmas Day.

The storm, which had formed just off the coast, came ashore as a Category 1 cyclone (equivalent to a tropical storm on the U.S. Saffir-Simpson scale) with wind gusts of up to 105 kph (~65 mph) reported just offshore. The Tropical Rainfall Measuring Mission satellite (known as TRMM) was launched back in 1997 with the primary purpose of measuring rainfall in the Tropics.

With its unique combination of active radar and passive microwave sensors, TRMM has also served as a valuable platform for monitoring tropical cyclones. TRMM captured an image of Tasha at 15:32 UTC (5:32 am AEST) on the 24th of December 2010 just before it became a Category 1 cyclone. Tasha appears as an area of enhanced rainfall with moderate to localized areas of heavy rain embedded within a broader area of light to moderate rain draped along the coast of northeastern Australia.

Tasha has no eye and little evidence of banding, which indicates that it is not an intense system. In fact, Tasha's winds did little damage and the storm was quickly downgraded from a cyclone by the Australian Bureau of Meteorology's Tropical Cyclone Warning Centre; however, heavy rains from the storm and its remnants had a substantial impact on the region by exacerbating flood conditions already in place as a result of prior excessive rainfall across eastern Australia. The result was widespread flooding with many areas cut off.

For increased coverage, TRMM can be used to calibrate rainfall estimates from other satellites. The TRMM-based, near-real time Multi-satellite Precipitation Analysis (TMPA) at the NASA Goddard Space Flight Center in Greenbelt, Md. is used to monitor rainfall over the global Tropics. TMPA rainfall totals were calculated for the period Dec. 1 to 29, 2010 for northeastern Australia and the surrounding region. Rainfall totals for the period exceed 300 mm (~12 inches) all along the northeast and northern coasts. Farther inland amounts drop off but still exceed 100 to 200 mm (~4 to 8 inches) over much of Queensland.

Although Tasha is responsible for dumping a lot of the rain over a short period (the Bureau had a report of up to 10 inches in 24 hours as a result of Tasha), eastern Australia had already been experiencing above normal rainfall as result of above normal ocean temperatures in the West Pacific due to La Nina.

La Nina, the counterpart to El Nino, occurs when enhanced trade winds pile up warmer-than-normal waters in the West Pacific while cooler-than-normal sea surface temperatures occur in the East Pacific. This leads to enhanced evaporation over the warmer water in the West Pacific with the excess moisture carried along by stronger-than-normal trade winds. The result is enhanced rainfall over the Maritime continent and northern and northeastern Australia during Northern Hemisphere winter (Southern Hemisphere summer) and drier-than-normal conditions over the Central and East Pacific.

TMPA rainfall anomalies for the month of December 2010 for the tropical Pacific and surrounding region were constructed by first computing the average rainfall rate over the period and then subtracting the 10-year average rate for the same period.

The resulting pattern shows a classic La Nina signature with above-normal areas of rain (shown in green and blue) over the Maritime continent and northeastern Australia and below-normal areas of rain (shown in brown over the Central Pacific. The estimated property damage from all the flooding in eastern Australia, which by some accounts is the worst in 50 years, is expected to exceed $1 billion.

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

Text Credit: Steve Lang
SSAI/NASA Goddard Space Flight Center, Greenbelt, MD










December 29, 2010

NASA's Terra Satellite Sees Tropical Storm Tasha After Landfall

MODIS captured a visible image of Tropical Cyclone Tasha inland over northeastern Australia. › View larger image
On December 25 at 0400 UTC (2 p.m. local time), NASA's Terra Satellite captured a visible image of Tropical Cyclone Tasha inland over northeastern Australia. The brightest white clouds indicated the highest, strongest thunderstorms within the tropical storm.
Credit: NASA Goddard/MODIS Rapid Response Team
Tropical Storm Tasha formed quickly in the South Pacific Ocean last weekend and made landfall on the coast of Queensland, Australia on Christmas day (local time). NASA's Terra satellite passed over Tasha after its center made landfall and captured a visible image of the storm revealing some powerful thunderstorms.

On Dec. 24, Tropical Storm Tasha formed quickly and headed for landfall near Cairns, Australia. At 1800 UTC (1 p.m. EST or 4 a.m. on Dec. 25 local time –Brisbane/Australia), Tasha was near 17.1S 146.3E, about 35 nautical miles east-southeast of Cairns with maximum sustained winds near 39 mph. At that time a NASA Tropical Rainfall Measuring Mission (TRMM) satellite image showed banding of thunderstorms and the storm was getting more organized.

On Dec. 24 at 3:14 p.m. EST (6:14 a.m. local time on Dec. 25), the Australia Bureau of Meteorology issued a Severe Weather Warning, calling for "damaging winds, heavy rainfall and further flooding for people about the Queensland coast, ranges and adjacent inland areas between Cardwell and St Lawrence." In addition, a High Surf Warning was posted.

On December 25 at 0400 UTC, which was 2 p.m. local time (Australia/Brisbane time), NASA's Terra Satellite captured a visible image of Tropical Cyclone Tasha inland over northeastern Australia. The satellite image showed an area of very bright white clouds around the center of the storm indicating the highest, strongest thunderstorms within the tropical storm. The image was created by the MODIS Rapid Response Team located at NASA's Goddard Space Flight Center in Greenbelt, Md.

Tasha was generating rainfall at up to 2 inches (50 mm) per hour before it made landfall, according to NASA's TRMM satellite data. That heavy rainfall combined with another weather system that affected Queensland and created record flooding as Tasha made landfall and moved inland.

Text Credit: Rob Gutro
NASA Goddard Space Flight Center, Greenbelt, MD



December 28, 2010

NASA's TRMM Satellite Captures Flooding in Queensland from Tasha and Another Storm

This color-coded image shows rainfall amounts in Queensland from December 20 to December 26, 2010. › View larger image
This color-coded image shows rainfall amounts in Queensland from December 20 to 26, 2010. The heaviest rainfall amounts—more than 400 millimeters or nearly 16 inches—appear in dark blue. The lightest amounts—less than 50 millimeters or 2 inches—appear in light green. The heaviest rainfall occurs along the northeastern Queensland coast. Relatively heavy amounts also occur inland, and along the Gulf of Carpentaria.
Credit: NASA TRMM/Jesse Allen/Earth Observatory
Heavy rains, some associated with Tropical Storm Tasha, battered the Queensland coast in late December 2010. The Tropical Rainfall Measuring Mission or TRMM satellite captured rainfall data that allowed visualizers at NASA's Goddard Space Flight Center in Greenbelt, Md. to map the heavy rainfall.

Tasha came ashore on December 25, 2010, just south of Cairns, according to the Herald Sun. As Tasha abated, a second low-pressure storm formed off the Queensland coast, promising more precipitation. Forecasters expected heavy rain for several more days in almost every major Queensland town. Eighteen rivers were on flood watch throughout the state as of December 27.

This color-coded image shows rainfall amounts in Queensland from December 20 to December 26, 2010. The heaviest rainfall amounts—more than 400 millimeters or nearly 16 inches—appear in dark blue. The lightest amounts—less than 50 millimeters or 2 inches—appear in light green. The heaviest rainfall occurs along the northeastern Queensland coast. Relatively heavy amounts also occur inland, and along the Gulf of Carpentaria.

The Herald Sun reported that, as eastern Australia flooded, the western part of the country sweltered, with some areas experiencing temperatures of more than 38 degrees Celsius (100 degrees Fahrenheit).

This image is based on data from the Multisatellite Precipitation Analysis produced at NASA’s Goddard Space Flight Center, which estimates rainfall by combining measurements from many satellites and calibrating them using rainfall measurements from the Tropical Rainfall Measuring Mission (TRMM) satellite.

Text Credit: Michon Scott
NASA's Earth Observatory
NASA Goddard Space Flight Center, Greenbelt, MD



December 24, 2010

Tropical Storm Tasha

This color-coded image shows rainfall amounts in Queensland from December 24, 2010. › View larger image
This image shows Tasha’s rainfall, as observed by the Tropical Rainfall Measuring Mission (TRMM), on December 24, 2010.
Credit: NASA/Tropical Rainfall Measuring Mission
Tropical Storm Tasha was short lived, but during its brief appearance in late December 2010, the storm pounded northeastern Australia with heavy rain. Tasha reached tropical storm strength on December 24 and made landfall along the Queensland coast the next day.

This image shows Tasha’s rainfall, as observed by the Tropical Rainfall Measuring Mission (TRMM), on December 24, 2010. Color-coded precipitation levels (red is the highest and blue is the lowest) are superimposed on a photo-like image. Large expanses of rainfall occur along the Coral Sea and the Gulf of Carpentaria, with pockets of particularly heavy rain near the Coral Sea coast.

Text Credit: Michon Scott
NASA's Earth Observatory
NASA Goddard Space Flight Center, Greenbelt, MD