Typhoon

Typhoon Melor (Nona) Dissipates After Raking Philippines (RECAP)

Former Typhoon Nona degenerated into a remnant low Thursday after cutting an east-to-west swath through the country, making landfall five different times along the way and bringing damage and destruction from storm surge, high winds and very heavy rainfall.

(MORE: Thousands of Homes Destroyed by Typhoon Nona)

The tropical cyclone, known internationally as Melor, made its first landfall in the Philippines Monday morning after undergoing a last-minute spurt of intensification over the open waters of the Pacific Ocean just east of the country's Visayas island chain. After weakening briefly and making three additional landfalls, it then underwent another spurt of rapid intensification Tuesday morning before its eye scraped ashore for a fifth time in northern Oriental Mindoro.

Nona (Melor) succumbed to a blast of northerly winds associated with a zone of Siberian high pressure that had dropped south through China. The winds helped rip apart the cyclone's ring of thunderstorms, cutting off its means of sustaining itself.

In its final advisory, the U.S. military's Joint Typhoon Warning Center said Nona (Melor) was dissipating about 165 miles (270 kilometers) west-southwest of Manila Thursday morning local time. (The Philippines are 12 hours ahead of U.S. Eastern Standard Time.)

(MORE: Hurricane Central)

Freshwater flooding continued Thursday in many areas of northern and central Luzon as a result of extremely heavy rainfall.

Rainfall totals of 12 to 20 inches (300 to 500 millimeters) were reported in some locations northeast of Manila. Cabanatuan City reported 493 millimeters (19.41 inches) of rain between 8 a.m. Tuesday and 2 a.m. Thursday local time.

The national government's disaster management agency said Typhoon Nona made its first landfall around 11 a.m. Monday on Batag Island near the northern tip of Northern Samar province.A second landfall occurred around 4 p.m. local time Monday near Bulusan in the Sorsogon province.

The eye of Typhoon Nona became much better defined as it approached the northern coast of the island of Samar in the eastern Philippines late Monday morning local time. Satellite-based intensity estimates from the University of Wisconsin-Madison suggested Nona's maximum wind speeds rapidly increased from approximately 100 mph (155 kph) at 3 a.m. Monday to about 135 mph (220 kph) by 10:20 a.m.

Bulletins from various government agencies have struggled to keep up with the evolution of the typhoon, which underwent an earlier spate of intensification early Sunday. That prompted the U.S. military's Joint Typhoon Warning Center (JTWC) to upgrade Nona (Melor) from a tropical storm to a Category 4 equivalent typhoon within an 18-hour span, but objective satellite estimates from UW-Madison suggested Melor probably topped out in the Category 2 range before its eye disappeared and its core appeared to become disorganized late Sunday.

The compact eye of the typhoon re-emerged in satellite imagery Monday morning less than three hours before touching the northeastern part of the island of Samar.

The Japan Meteorological Agency (JMA) reacted by raising its estimate of the typhoon's winds from 90 mph (145 kph) to 110 mph (180 kph) between 2100 GMT Sunday and 0000 GMT Monday. JMA said top winds remained at 110 mph (180 kph) at 0900 GMT Monday which is close to the time that Nona was making landfall. (Japan uses a more conservative wind-measuring method than the U.S., taking an average over 10 minutes instead of 1 minute.)

Meanwhile, JTWC dropped Nona (Melor) to a Category 3 equivalent at 1800 GMT Sunday and left it at that intensity as of 0000 GMT Monday, assigning the storm maximum sustained winds of 125 mph. JTWC raised the intensity slightly to 130 mph (Category 4) just prior to landfall at 0600 GMT.

Western Pacific tropical cyclones, known as typhoons when they reach hurricane-equivalent status, can form any time of year.

Owing partially to this year-round calendar of potential development, roughly one-third of all the Earth's tropical cyclones form in the western Pacific Basin. On average, 25 tropical cyclones form each year in the western Pacific Basin, with 15 or 16 of those strengthening to Category 1 equivalent typhoons.

Just over a year ago, the central Philippines where hit by another strong typhoon in December. Typhoon Hagupit - known as Ruby in the Philippines - made landfall on Dec. 6 near Dolores in eastern Samar as a Category 3 equivalent.