NASA Infrared Data Compares Super Typhoon Jelawat with Tropical Storm Ewiniar
Tropical Storm Ewiniar (Pacific Ocean)
NASA's Aqua satellite has been obtaining infrared, visible and other data everytime it passes over Typhoon Jelawat and Tropical Storm Ewiniar in the western North Pacific, and a combination of two images from Aqua's AIRS satellite puts the storms in perspective.
A combined image created from infrared data obtained by the Atmospheric Infrared Sounder (AIRS) instrument that flies on NASA's Aqua satellite provides a comparison of the two monster storms in the western North Pacific Ocean basin . An infrared image of Typhoon Jelawat captured on Sept. 25 was combined with an image of Tropical Storm Ewiniar, that was taken on Sept. 24. The combined image gives perspective of the distance of the tropical cyclones from each other. The image showed the close proximity of the storms. Earlier in the week, Jelawat's outflow was affecting Ewiniar and preventing it from strengthening more quickly.
The data also showed a visible eye in the center of super typhoon Jelawat in the middle of powerful thunderstorms with very cold cloud top temperatures that exceed -63 Fahrenheit (-52 Celsius). Jelawat also has a rounded shape indicating that circulation is strong and symmetrical. Tropical Storm Ewiniar, however, appears somewhat asymmetrical, in the form of an elongated comma shape. The comma's "tail" is a large band of strong thunderstorms wrapping into Ewiniar's center from the southeast.
The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured a natural-color image on September 24, 2012, showing Jelawat just east of the Philippines. Sporting a distinct eye and spiral arms characteristic of strong storms, Jelawat spanned hundreds of kilometers (miles). As of September 24, 2012, the Joint Typhoon Warning Center (JTWC) classified Jelawat as a super typhoon. For the MODIS image, visit: http://lance-modis.eosdis.nasa.gov/cgi-bin/imagery/single.cgi?image=Jelawat.A2012268.0430.2km.jpg
Jelawat remains a super typhoon today, Sept. 25, with maximum sustained winds near 140 knots (161 mph/259 kmh). It is located 385 nautical miles east-northeast of Manila, Philippines, and is moving north-northwestward at 6 knots (7 mph/11 kmh). Satellite imagery is showing tightly wrapped bands of thunderstorms spiraling into the eye of the storm. The eye is about 17 nautical miles wide. High pressure in the upper atmosphere and low wind shear are helping the super typhoon maintain its intensity. The JTWC projected storm track showed the storm moving toward the north-northwest over the next several days, passing near the island of Taiwan before turning toward the northeast.
NASA's Goddard Space Flight Center
, Greenbelt, Md.
Sept. 24, 2012
Frigid Cloudtop Temperatures Indicate Strength in Super Typhoon Jelawat and Tropical Storm Ewiniar
Tropical Storm Jelawat had been moving toward the Philippines since the week of Sept. 17 and on Sept. 24 it became a super typhoon east of the country. Meanwhile, the nineteenth tropical depression formed just east of Jelawat in the western North Pacific Ocean and quickly strengthened into a tropical storm. Both storms were captured on one infrared image from NASA's Aqua satellite.
The Atmospheric Infrared Sounder (AIRS) instrument aboard NASA's Aqua satellite revealed a large area of powerful thunderstorms around the center of Typhoon Jelawat and a band of thunderstorms west of the center on Sept. 23. Those thunderstorms continued to strengthen on Sept. 24 and cloud top temperatures exceeded -63 Fahrenheit (-52 Celsius). Cloud top temperatures are an indication of uplift in a storm. Uplift is the push of air upward that allows formation of towering clouds and thunderstorms that make up a tropical cyclone.
Jelawat's center continues to stay east of the Philippines, but is causing rough surf (with wave heights up to 37 feet/11.2 meters) along the eastern coasts of the country and its large extent is bringing rains and gusty winds as well.
Jelawat is a powerful Super Typhoon with a clear 23 nautical mile-wide eye and maximum sustained winds near 130 knots (149.6 mph/240.8 kmh).Jelawat is a Category 4 typhoon on the Saffir-Simpson scale. It is located near 15.0 North latitude and 127.9 East longitude, approximately 410 nautical miles (472 miles/759 km) east of Manila, Philippines. Jelawat's minimum central pressure is near 926 millibars. Jelawat is forecast to track to the northwest through the Philippine Sea and move toward Taiwan.
Tropical Storm Ewiniar had maximum sustained winds near 35 knots (40 mph/64.8 kmh) on Sept 24 at 1500 UTC (11:00 a.m. EDT). It was centered near 20.9 North and 138.9 East, a 300 nautical miles (345 miles/555.6 km) south-southwest of Iwo To. AIRS data showed that the low-level center is slowly consolidating (organizing) and becoming less elongated. The strongest convection and thunderstorms were seen in a band of thunderstorms east of the center of circulation. Ewiniar is getting organized slowly because of westerly wind shear caused by nearby Typhoon Jelawat.
The Joint Typhoon Warning Center expects Ewiniar to track to the north-northeast and affect Iwo Two tomorrow, Sept. 25 as it continues in a northeasterly direction.
NASA's Goddard Space Flight Center
, Greenbelt, Md.