Atlantic tropical cyclone activity. Graphic by NHC/NOAA

MIAMI, USA – As Katia became a major hurricane on Monday, the biggest threat from the storm continued to be dangerous rip currents likely to affect Bermuda. However, another tropical system is developing southwest of the Cape Verde Islands and is moving in the general direction of the Caribbean.

At 5:00 pm EDT on Monday, the National Hurricane Center in Miami reported that the centre of Hurricane Katia was located about 495 miles south of Bermuda, with maximum sustained winds of115 mph — category three on the Saffir-Simpson hurricane wind scale.

Katia is moving toward the northwest near 12 mph and this general motion, with a slight decrease in forward speed, is expected through Wednesday.

Large swells generated by Katia are expected to affect Bermuda, the Greater Antilles and east-facing beaches of The Bahamas during the next few days. These swells are likely to cause life-threatening surf and rip current conditions. Swells affecting the northern Leeward Islands should continue to subside.

Meanwhile, a vigorous tropical wave, accompanied by a broad surface low pressure system, is located about 550 miles southwest of the Cape Verde Islands.

This large disturbance became much better organized on Monday and environmental conditions are expected to remain conducive for a tropical depression to form during the next day or so. This system has a high chance — 60 percent — of becoming a tropical cyclone during the next 48 hours as it moves westward to west-northwestward at about 15 mph.