15 Sept 2016

NASA Sees Atlantic Tropical Depression 12 Come Together

The twelfth tropical depression of the Atlantic Ocean season formed a day after the eleventh. Tropical Depression 12 formed in the far eastern Atlantic near the Cape Verde Islands. The NASA-NOAA Suomi NPP satellite showed very cold cloud top temperatures indicative of strong thunderstorms in the northern quadrant of the storm.
On Sept. 14 at 10:59 a.m. EDT (1459 UTC) the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard the NASA-NOAA Suomi NPP satellite captured an infrared image of Tropical Depression 12. VIIRS infrared data shows temperature and revealed that cloud tops north and northwest of the center were as cold as minus 70 degrees Fahrenheit (minus 56.6 degrees Celsius). Cloud top temperatures that cold indicate storms stretching high into the troposphere and have been shown to generate heavy rain.

VIIRS collects visible and infrared imagery and global observations of land, atmosphere, cryosphere and oceans.
At 11 a.m. EDT (1500 UTC) on Sept. 14 the center of Tropical Depression Twelve (TD12) was located near 17.0 degrees north latitude and 25.0 degrees west longitude. That's about 95 miles (155 km) northwest of the Cape Verde Islands. The National Hurricane Center (NHC) said the depression is moving toward the west-northwest near 14 mph (22 kph) and a gradual turn toward the west is expected during the next couple of days. On the forecast track, the center of the depression should move away from the islands during the night-time hours of Sept. 14.

Maximum sustained winds are near 35 mph (55 kph) with higher gusts. Slight strengthening is expected during the next 24 hours, and the depression could become a tropical storm tonight, Sept. 14. After that time, some weakening could occur as the cyclone encounters unfavorable upper-level winds.
NHC forecaster Jack Beven said in the 11 a.m. EDT discussion, "Locally heavy rains and gusty winds are possible over the Cape Verde Islands. However, current indications are that the cyclone will not reach tropical-storm strength until it has moved west of the islands."

Image: On Sept. 14 at 10:59 a.m. EDT NASA-NOAA's Suomi NPP satellite showed cloud tops north and northwest of the center (red) were as cold as minus 70 degrees Fahrenheit (minus 56.6 degrees Celsius).