what lead it to become a typhoon?
Development of a high pressure ridge as Omar moved away from another typhoon.
Typhoon Omar
 However, as Omar and Polly moved farther apart, a high-pressure ridge developed between the storms. This caused Omar to drift northward and then west-northwestward into a region with decreased shear, which allowed it to resume strengthening. Early on August 27, the JTWC upgraded the system to a typhoon,
when did typhoon omar take place? In 1992. where did it start? From the monsoon trough in the western Pacific Ocean.
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Typhoon Omar [SEP] Meteorological history
The JTWC estimated higher 1‑minute winds of around 240 km/h (150 mph), making Omar a super typhoon. Two days later, the typhoon came close enough to the Philippines to warrant monitoring from PAGASA, who named the storm "Lusing". By 1500 UTC on September 3, the JMA downgraded Omar to a tropical storm, although the JTWC maintained its typhoon intensity through the next day. Heading generally westward, the storm made landfall on the east coast of Taiwan near Hualien City on September 4. After traversing the island in seven hours, Omar exited the coast of Yunlin County and emerged into the Taiwan Strait.