Typhoon Omar of 1992, known in the Philippines as Typhoon Lusing, was the strongest and costliest typhoon to strike Guam since Typhoon Pamela in 1976. The cyclone formed on August 23 from the monsoon trough across the western Pacific Ocean. Moving westward, Omar slowly intensified into a tropical storm, although another tropical cyclone nearby initially impeded further strengthening. After the two storms became more distant, Omar quickly strengthened into a powerful typhoon. On August 28, it made landfall on Guam with winds of 195 km/h (120 mph). The typhoon reached its peak intensity the next day, with estimated 1‑minute winds of 240 km/h (150 mph), making it a "super typhoon" according to the Joint Typhoon Warning Center (JTWC). Omar weakened significantly before striking eastern Taiwan on September 4, proceeding into eastern China the next day and dissipating on September 9. On Guam, Omar caused one death and $457 million (1992 USD) in damage. Strong gusts up to 248 km/h (154 mph) left nearly the entire island without power for several days. The outages disrupted the water system and prevented the island-based JTWC from issuing advisories for 11 days. Omar damaged or destroyed 2,158 houses, leaving 3,000 people homeless. In response to the destruction, the island's building codes were updated to withstand winds of 250 km/h (155 mph), and insurance companies discontinued new policies for structures not made of concrete. While passing well north of the Philippines, the typhoon killed 11 people and wrought ₱903 million ($35.4 million) worth of damage to 538 houses. Omar then brushed the southern islands of Japan with strong gusts and light rainfall, causing ¥476 million JPY (US$3.8 million) in crop losses. In Taiwan, scattered flooding caused three deaths and $65 million in damage, mostly to agriculture. Meteorological history Typhoon Omar originated from a tropical disturbance that was first noted on August 20 over the open Pacific Ocean, which exhibited persistent convection, or thunderstorms. During this early phase, two tropical cyclones dissipated and another became extratropical across the western Pacific basin; this caused the monsoon trough, which spawned most of the storms in the basin, to realign in a more climatologically appropriate manner. According to the Japan Meteorological Agency (JMA), Omar developed into a tropical depression at 1800 UTC on August 23. The Joint Typhoon Warning Center (JTWC) assessed a slower pace of strengthening, issuing a tropical cyclone formation alert at 2100 UTC before initiating advisories