On October 6, Tropical Storm Marco formed in the Bay of Campeche. It developed from a well organized, but very small, low. With the low amount of vertical wind shear and relatively warm sea surface temperatures, Marco was able to quickly intensify, but remained just below hurricane status as it made landfall in Veracruz. Its maximum winds were at the time of landfall and were measured at 100 km/h (65 mph). Marco's lowest pressure was measured to be 998 mb. More information on Marco is available from the NOAA National Hurricane Center.

Tropical Storm Nana formed over the eastern Atlantic on the afternoon of October 12. As a tropical storm, Nana traveled to the west-northwest. While on this track it encountered strong westerly shear which displaced its convection away from the center. The storm remained disorganized during its short lifespan and on October 14, the National Hurricane Center issued its final advisory. The maximum wind speed was measured at 65 km/h (40 mph) and its lowest pressure was measured at 1000 mb. More information on Nana is available from the NOAA National Hurricane Center.

On October 13, Tropical Depression Fifteen formed from an area of low pressure in the Caribbean Sea and was guided northwestward by light steering currents. The depression strengthened enough by the next day to be named Tropical Storm Omar. During this time, Omar was moving towards the southeast, but just as quickly it turned to the north-northeast, and intensified into a hurricane. By October 15, Omar had intensified into a Category 3 storm with sustained winds of 205 km/h (125 mph) and a pressure of 959 mb. Omar was the fourth major hurricane of the 2008 Atlantic Hurricane Season. On the 16th, Omar entered cooler waters and experienced high wind shear, thus weakening it to a tropical storm and on the 18th, Omar had degenerated into a remnant low. Omar's unusual path caused some minor damage to the Leeward Islands as it became the first westward traveling hurricane to strike that area since Hurricane Lenny of 1999. More information on Omar is available from the NOAA National Hurricane Center.

On October 8, the seventeenth tropical depression of the 2008 Eastern Pacific season formed from a low pressure near Nicaragua. As the storm moved to the northwest, it strengthened into Tropical Storm Odile. Over the course of the next several days the storm strengthened and tropical storm watches were issued in Mexico. Odile never made landfall, but it did come within 50 miles of the coast. Its peak winds were measured at 100 km/h (65 mph) and its lowest pressure was measured to be 996 mb. More information on Tropical Storm Odile is available from the NOAA National Hurricane Center.

On October 3, a broad area of low pressure developed into Tropical Depression Fifteen-E. The next day, as the vertical wind shear weakened and the storm moved over relatively warm water, it developed into Tropical Storm Norbert. Norbert's cloud pattern continually increased in organization during the following days and by the 6th, the storm had developed into a hurricane. As the storm traveled to the west-northwest it encountered favorable upper-level winds and warm ocean temperatures which helped Norbert increase in intensity while becoming a major hurricane. In fact, Norbert became the 2nd major eastern Pacific hurricane on October 8, with winds of 185 km/h (115 mph). Later that afternoon, Norbert's winds were measured at 213 km/h (132 mph), enough to reach category 4 status. By October 11, Hurricane Norbert had weakened into a Category 2 storm as it made landfall first in Baja, California, then again in the Mexican state of Sonora. Winds at the time of its second landfall were measured to be 155 km/h (96 mph). Its maximum winds were measured to be 220 km/h (140 mph) and its lowest measured pressure was at 945 mb. Norbert was the first October hurricane to strike the western Baja California peninsula since Hurricane Pauline of 1968. More information on Hurricane Norbert is available from the NOAA National Hurricane Center.

On October 1, Marie developed from a low pressure area off the south-west coast of Baja, California. Later that same day, it developed into a tropical storm, but it took an additional two days for Marie to be declared a hurricane. This was the first eastern Pacific storm to develop into a hurricane since Hernan, two months earlier. Hurricane Marie had a small, but well defined eye that was 12 nautical miles wide at one point in time, but by the evening of the 3rd, the eye started to become poorly defined. The storm continued to weaken as it moved over the cooler waters of the Eastern Pacific. By the evening of October 4, Marie had been downgraded to a tropical storm and on October 6, the National Hurricane Center issued its last advisory. Hurricane Marie had a top wind speed of 130 km/h (80 mph) and its lowest measured pressure was 984 mb. More information on Hurricane Marie is available from the NOAA National Hurricane Center.