The typhoon made several landfalls in Sorsogon, Burias Island, Romblon, and Oriental Mindoro, before weakening into a tropical storm.

During December 10, the Japan Meteorological Agency started to monitor a tropical depression, that had developed about 665 km (415 mi) to the south of Guam.

[1][2] The system was located within a favorable environment for further development, with low vertical wind shear and sea surface temperatures of between 29–30 °C (84–86 °F).

[3] Based on a developing low-level circulation center (LLCC) obscured by the mid-level deep convection in an area of strong westward upper-level diffluence and moderate easterly vertical wind shear, the Joint Typhoon Warning Center (JTWC) issued a Tropical Cyclone Formation Alert (TCFA) to the system early on December 11.

[8][9] Due to low vertical wind shear, warm sea surface temperatures above 28°C and robust poleward outflow enhanced by a very powerful Aleutian low, Melor intensified into a typhoon early on December 13, as tightly curved spiral banding was observed wrapping into a tiny but clear eye.

[12][13] Melor made landfall over Batag Island of Laoang, Northern Samar of the Philippines at 11:00 PST (03:00 UTC) on December 14.

The JMA reported a peak intensity of ten-minute maximum sustained winds at 175 km/h (110 mph) and a central pressure of 935 hPa (27.61 inHg).

The typhoon formed a well-defined eye and then maintained it for several hours while crossing the northern coast of Samar.

Right before making its fifth landfall on Pinamalayan, Oriental Mindoro at 10:30 PST (02:30 UTC), the JTWC indicated that Melor had reached peak intensity with one-minute maximum sustained winds at 230 km/h (145 mph), just shy of the super typhoon status.

Inflow along the southwestern quadrant was forced over the mountainous central terrain of Mindoro, and strong poleward outflow was also weakening owing to the decreasing linkage to mid-latitude flow.

The JMA downgraded Melor to a tropical storm at noon, although the system's convection had been sheared away from the low-level circulation center.

[23][24] Several of meteorological agencies downgraded Melor to a tropical depression early on December 17, including the JMA and JTWC, who issued final warnings on the system;[25] however, satellite imageries depicted an open trough instead of a discernable LLCC.

[47][48] Several areas in Central Luzon, mostly in Nueva Ecija, Bulacan, Pampanga, Tarlac, Isabela, and Aurora, were flooded by rain caused by Typhoon Nona.

However, owing to its similarity to President Benigno Aquino III's nickname, "Noynoy", PAGASA renamed the typhoon "Nona", despite that name's usage during 2011.