Tropical Storm 27W Forming

Tropical Cyclones can form in the western Pacific Ocean at any time during the year but they occur most frequently during the months of June through November so tropical storm 27W is a little unusual. The TRMM satellite saw what was then tropical depression 27W on 13 December 2011 at 1533 UTC. It was upgraded to a Tropical storm by the Joint Typhoon Warning Center (JTWC) the next day at 0900 UTC. TRMM's Microwave Imager (TMI) shows that moderate rainfall was located in clusters of strong convective storms within the developing tropical cyclone.

TRMM image of tropical cyclone 27W

Tropical storm 27W has been predicted to intensify to minimal typhoon strength with winds of 65 kts (~75 mph) before moving over the southern Philippines in the next couple days. In a typical year 6-9 tropical cyclones cross over the Philippines. This year has been unusually deadly with typhoons Nesat and Nalgae causing heavy flooding and loss of life in the Philippines in late September and early October.