The low that forecasters were watching for development yesterday, March 9, strengthened into Tropical Storm Hubert, and is already making landfall in eastern Madagascar.
The Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua satellite captured Tropical Storm Hubert's cold thunderstorm cloud tops on March 10 at 5:11 a.m. ET as the western edge of the storm was already raining on eastern Madagascar. The infrared imagery showed two areas where convection was strong in Hubert: the northeastern and southern quadrants of the storm. It is in those two areas that the highest, coldest thunderstorm tops were revealed by AIRS infrared imagery. Those thunderstorm cloud tops were as cold as -63 Fahrenheit!
Hubert has maximum sustained winds near 39 mph (35 knots) and is moving west-southwest near 6 mph (5 knots). At 10 a.m. ET (1500 UTC) on March 10, Hubert was located about 160 nautical miles southeast of the capital city of Antananarivo, Madagascar near 20.9 South and 48.8 East.
As Hubert continues moving inland over the next two days, forecasts for the capital city and other areas in south central Madagascar will continue to experience periods of moderate to heavy rainfall, and gusty winds.
Animated multispectral satellite imagery showed a loss of central convection as Hubert's center moves closer to a landfall. Once Hubert's center is over land, forecasters expect Hubert will quickly fall below tropical storm strength.
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