NASA-NOAA's Suomi NPP satellite passed over Tropical Storm Dujuan on Sept. 23 and saw a large and elongated circulation.
Tropical Depression 21W has strengthened into a tropical storm and has been renamed Tropical Storm Dujuan.
On Sept. 23 at 0442 UTC (12:42 a.m. EDT) infrared data from the Visible Infrared Imaging Radiometer Suite or VIIRS instrument that flies aboard Suomi NPP showed cloud top temperatures west of the elongated center of Tropical Storm Dujuan were as cold as -63F/-53C, indicating strong storms reaching high into the troposphere. The Joint Typhoon Warning Center (JTWC) noted that elongated bands of shallow or weaker thunderstorms were forming around the low level center of circulation.
VIIRS is a scanning radiometer that collects visible and infrared imagery and "radiometric" measurements. Basically it means that VIIRS data is used to measure cloud and aerosol properties, ocean color, and ocean and land surface temperatures. The Suomi NPP satellite is co-managed by both NASA and NOAA.
By 1500 UTC (11 a.m. EDT), Tropical Storm Dujuan's maximum sustained winds were near 45 knots (51.7 mph/83.3 kph). Dujuan's center was near 18.3 North latitude and 134.7 East longitude, about 623 nautical miles (717 miles/1,154 km) southeast of Kadena Air Base, Iwo To, Japan. It was moving to the west at 10 knots (11.5 mph/18.5 kph).
For watches and warnings from the Japan Meteorological Agency, visit: http://www.jma.go.jp/jma/indexe.html.
JTWC expects Dujuan will move west, and then turn north-northwest. Dujuan is expected to continue to intensify and will peak at 110 knots (126.6 mph/203.7 kph) on passing south of Okinawa, Iwo To, Japan on Sept. 27 and 28.
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