The system had a broad circulation amid an environment favorable for tropical cyclogenesis, including low to moderate wind shear.
[4] At 06:00 UTC on May 2, the Japan Meteorological Agency (JMA) designated the system as a tropical depression about 850 km (530 mi) west-southwest of Chuuk.
[7] Aided by decreasing wind shear and warm sea surface temperatures, the convection organized into a central dense overcast.
[5] (Korean: 노을; literally: afterglow, red sky)[9] The strengthening ridge turned the storm to the west toward the Philippines.
[13] Early on May 7, Noul crossed 135º E into the area of responsibility of PAGASA – the Philippines' weather bureau – who assigned the local name Dodong.
[14] Due to radial outflow, low vertical wind shear, and water temperatures above 30°C, Noul started rapid deepening on May 9 while approaching the Philippine island of Luzon, forming a sharply well-defined 35 km (22 mi) eye embedded in a deepening symmetric core; therefore, the JTWC upgraded it to a super typhoon late on the same day.
[16] As the typhoon neared the northeast tip of Luzon, satellite imagery showed rapid deterioration of the storm's core structure and warming of the cloud tops.
After its closest approach to Luzon, the storm's structure continued to deteriorate, becoming elongated and less organized due to increasing wind shear and land interaction.
[18] By late on May 10, the eye largely disappeared from satellite imagery as Noul turned northward over water, steered around the subtropical ridge.
[19] A large residual eye persisted in the center of the waning convection,[20] although stronger wind shear increasingly disrupted the storm's structure.
[21] By early on May 12, the storm had become increasingly elongated as dry air became entrained in the center, with the structure resembling a "comma"-shape, according to the JTWC.
At 06:00 UTC on May 16, the remnants of Noul dissipated near the International Date Line,[5] after being absorbed by another large extratropical storm.
[28] The storm delayed a supply ship to outlying islands of the state that were previously affected by Typhoon Maysak a month prior.
In response to the storm, PAGASA raised warning signal 4, the highest level, for northeastern Cagayan as well as the offshore Batanes and Babuyan Islands.
[30] People were also evacuated from the vicinity of Mount Bulusan after rains from Noul threatened to cause lahars and mudslides from ash of a recent eruption.
A total of 93 mm (3.7 in) of rain fell at the Shihmen Dam,[37] amounting to an increase of approximately 7 million tonnes of water in the reservoir,[38] and bringing it to 30.5% capacity.
[46] The remnants of Noul, in conjunction with later Typhoon Dolphin, shifted the broader weather pattern to bring record warmth to Alaska, making the temperatures warmer than that of Washington, D.C.[47]