Otto very close to becoming season's 7th hurricane

Just to keep everyone on their toes during the final homestretch of hurricane season, Tropical Storm Otto is lurking in the southwest Caribbean Sea.  Yesterday morning, it was just a tropical depression, and then was upgraded to a tropical storm later in the day as expected.  As of Tuesday morning, it is nearly a hurricane with peak sustained winds of 70 mph.

Otto is still on track to make landfall near the Nicaragua/Costa Rica border on Thanksgiving, then cross over into the eastern Pacific where it is expected to dissipate.  Hurricane watches have been issued for the area, while tropical storm watches and warnings cover much of Panama's northern coast.  If the center hits Costa Rica, it would be that country's first hurricane landfall on record.

The water temperature east of Nicaragua and Costa Rica is quite warm, around 28°C, which is plenty to sustain a hurricane.  The vertical wind shear has also decreased noticeably in the past couple of days.

The area where Otto is forecast to make landfall is sparsely populated, but as with all landfalling tropical cyclones, the risk of heavy rain and resulting flooding extends far from the center, and the mountainous areas of Nicaragua and Costa Rica could see 10-15 inches of rain in the coming days.

This is the 7th time that the name Otto has been on a name list since 1980, and it only got used in the past 3 of those 7 times (2004, 2010, 2016).  The next name on the list is Paula, though it's very unlikely that another named storm will form this year.

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