Favorable environmental conditions, such as low wind shear and warm sea surface temperatures, allowed the system to intensify into a severe tropical storm by July 12.

After brushing the island at peak intensity with sustained winds estimated at 130 km/h (80 mph), the storm weakened in the Gulf of Tonkin due to less favorable conditions.

Late on July 9, the Joint Typhoon Warning Center (JTWC), reported that a tropical disturbance had persisted within the vicinity of Yap island.

[1] During the next day, deep convection around the disturbance increased whilst a low to mid level circulation center appeared on satellite imagery.

[7] At 0000 UTC, the next day the JMA reported that Basyang had intensified into a weak tropical storm and assigned it the name Conson and the international designation of 1002.

Later that day at 1800 UTC the JTWC reported that after convection around the system had expanded and microwave imagery showed an eye-like feature, Conson had intensified into a typhoon.

The JMA also reported at 1800 UTC that Conson had reached its initial 10-minute peak sustained windspeeds of 110 km/h (70 mph) despite predicting that it would intensify into a typhoon before making landfall in the Philippines.

Late on July 11, as they christened the tropical depression as Basyang, PAGASA placed the provinces of Cagayan, Isabela and Aurora under Storm Signal Number One, warning them to prepare for flash floods, landslides and strong winds.

Later that day, PAGASA placed the provinces of Catanduanes, Camarines Norte, Polillo Island, Aurora, Quirino and Isabela under Storm Signal Number Two while placing the provinces of Camarines Sur, Albay, Quezon, Rizal, Bulacan, Nueva Ecija, Nueva Vizcaya, Ifugao, Benguet, Mt.

Province, Kalinga, Pampanga, Tarlac, Pangasinan, La Union, Abra, Ilocos Sur under Storm Signal Number One.

They also placed Camarines Sur, Laguna, Rizal, Bulacan, Nueva Ecija, Nueva Vizcaya, Quirino, Ifugao and Isabela under Storm Signal Number Two and Metro Manila, Albay, Marinduque, Batangas, Cavite, Bataan, Pampanga, Zambales, Tarlac, Pangasinan, La Union, Benguet, Mt.

After Conson had made landfall in Southern Luzon, PAGASA placed Metro Manila under Storm Signal Number Two.

During the afternoon of July 15 the China Meteorological Agency issued a Yellow typhoon warning for parts of Hainan Province and the western Guangdong coast.

The Department of Water Resources stated that there was a likelihood that the storm would produce significant flooding across the region as rainfall between 100 and 200 mm (3.9 and 7.9 in) was anticipated.

At regional airports, air traffic officials canceled 29 international and local flights due to dangerous flying conditions brought about by the storm.

[14][15] 15 Philippine Airlines flights from different airports were canceled due to heavy rain, gusty winds and near zero visibility.

Roughly 500 passengers in Bicol and Quezon Province were stranded at their respective ports as the coast guard declared that ships may not depart due to high waves and heavy rains.

As the storm moved inland, strong winds caused widespread power outages in Quảng Ninh Province.

Later that same day, President Benigno Aquino III reprimanded PAGASA for failing to predict that Conson would pass over Manila.

[34] Three vessels of the Vietnamese navy were sent to the region near the Paracel Islands to search for the trace of 27 fishermen which had been missing since July 17.