Hurricane Norbert (1984)

Hurricane Norbert

Category 4 major hurricane (SSHWS/NWS)
Norbert on September 23.
Formed	September 14, 1984
Dissipated	September 26, 1984
Highest winds	1-minute sustained: 130 mph (215 km/h)
Fatalities	None
Damage	Minimal
Areas affected	Baja California Sur, Sonora, Arizona
Part of the 1984 Pacific hurricane season

Hurricane Norbert marked the first time a core of a hurricane was fully mapped in three-dimensions. First forming on September 14, 1984 west of the Mexican coast, Norbert gradually intensified, reaching hurricane intensity two days after formation. On September 22, Norbert peaked in strength as a Category 4 hurricane on the Saffir-Simpson Hurricane Scale. While intensifying, Norbert meandered. It moved east, then north, then west, then south, then back towards the east, and finally towards the northeast. After fluctuating in intensity for two more days, Norbert rapidly weakened. It turned towards the northwest and made landfall in southern Baja California Norte as a tropical storm. The combination of Norbert and several other storms left thousands homeless throughout Mexico. The remnants of Hurricane Norbert produced moderate rain over Arizona.

A tropical depression first developed on September 14 over the Pacific Ocean west of the Mexican coast. Six hours later, the depression intensified into Tropical Storm Norbert. Gradually strengthening, Norbert meandered in the weak steering currents for several days. The rate of intensification accelerated early on September 16, and shortly thereafter Norbert became a hurricane.

On September 17, Norbert turned from the east to the north, and upon attaining Category 2 status on the Saffir–Simpson Hurricane Scale at 1800 UTC the next day, Norbert began to turn back to the west. Several hours later, Norbert was upgraded to a major hurricane (Category 3 or higher). While maintaining its intensity for two and a half days, Norbert then turned to the south and after slight strengthening, back to the east. At 0000 UTC, September 21, Norbert reached its peak intensity of 130 mph (210 km/h). Meanwhile, a deep layer ridge over the Rocky Mountains was replaced by an upper-level trough, which extended south of Cabo San Lucas. This change in the steering patterns caused Hurricane Norbert to eventually turn to the northwest.