The Finnish nuclear power plant sees the development of tropical cyclone 06A from Orbi
Images from NASA-NOAA’s Suomi NPP satellite showed that the tropical depression in the Arabian Sea has strengthened and organized despite the wind shear. Tropical Depression 06A is now Tropical Cyclone 06A.
The Finnish Nuclear Power Plant’s Visible Infrared Imaging Radiometer Suite (VIIRS) provided a visible image of 06A, which revealed strong storms northwest of the center of rotation, but the storm was able to intensify despite the harsh environmental conditions. The center of motion can be seen in the VIIRS image as a small circulation area, located southeast of the clouds and rain showers.
In general, wind shear is a measure of how the speed and direction of the wind change with altitude. Tropical cyclones are like spinning cylinders of wind. Each level must be stacked vertically on top of each other in order for the storm to maintain its strength or intensify. Wind shear occurs when winds at different levels of the atmosphere push against a rotating wind cylinder, weakening the rotation by pushing it apart at different levels. In the case of Tropical Cyclone 06A, southeasterly winds push most of the storm clouds to the northwest.
The Joint Typhoon Warning Center, or JTWC, in Pearl Harbor, Hawaii noted: “Fully exposed low-level circulation center in animated multispectral satellite images. Strong (20-30 knots / 23-34.5 mph / 32-55.5 km/h) vertical wind shear offsets good poleward outflow and warm (28 to 29 degrees Celsius/82.4 to 84.2 degrees Fahrenheit) sea surface temperatures, making it difficult to intensify.” Tropical cyclones require sea surface temperatures of at least 26.6 degrees Celsius (80 degrees Fahrenheit) to maintain their strength or intensify, so warmer sea surface temperatures allow 06A to maintain its strength.
At 10 a.m. EST (1500 UTC) on December 3, the JTWC noted that 06A had maximum sustained winds near 35 knots (40 mph/65 kmph). 06A was located near latitude 7.1 degrees north and longitude 57.4 degrees east. It was about 784 nautical miles east-northeast of Mogadishu, Somalia.
However, it moves to the northeast, and the track slowly turns west-southwest as the subtropical ridge (an elongated area of high pressure) forms back to the north.
Tropical Cyclone 06A is forecast to make landfall in east-central Somalia on December 6 as a tropical storm.
Tropical cyclones and hurricanes are the most powerful weather phenomena on Earth. NASA’s space and scientific research expertise contributes to essential services provided by other federal agencies to the American people, such as hurricane forecasting.