A system caused by the interaction of a tropical wave with a mid to upper level low will spread moderate to heavy rainfall from the Leeward Islands to Puerto Rico and part of Hispaniola this weekend. Conditions in the BVI are expected to intensify tonight and into the weekend, especially on Saturday and the BVI DDM has issued a small craft and swimmers warning. The heavy rainfall could trigger the issuance of flash flood watches or warning.
At 8.00am, the eye of the storm was about 180 miles (290 km) away from Tortola. If the system keeps moving at its current speed of 16 mph, the eye of Tropical Storm Erika will be over Tortola at approximately 7.00pm tonight. However, with tropical storm force winds extending outwards 105 miles from the centre, tropical storm winds will start being felt at about 1.00pm today.
Erika will move over warmer waters as it tracks northwestward, but vertical wind shear will only allow for modest strengthening over the next 24 hours. Once the system moves north of the Lesser Antilles, wind shear values will decrease and more robust development may become possible. At 5:00 a.m., the centre of Tropical Storm Erika was located near latitude 14.6 degrees north, longitude 49.4 degrees west or about 1023 miles east-southeast of the BVI. Erika is moving toward the west near 20 miles per hour (mph). A westward to west north-west trend with a slight decrease in forward speed is expected in 48 hours. On the forecast track, the center of Erika will approach the Leeward Islands Wednesday night and early Thursday.
At 11:00 a.m., the center of what was Tropical Storm Danny was located near latitude 16.0 degrees north, longitude 62.0 degrees west or about 220 miles east-southeast of the British Virgin Islands. The low pressure system is moving toward the west near 12 miles per hour (mph). Maximum sustained winds are near 30 mph with higher gusts. The trough is expected to dissipate in a few days.
Danny is down to a 40 mph tropical storm and could weaken to a depression over the next 6 hours. It should weaken to a remnant low or tropical wave in 24 hours. Only minor impacts from heavy rain in squalls are possible. Sustained winds are expected to peak in the 20-25 mph range, with gusts to 35 mph possible. No significant impacts are expected.
Danny has officially been downgraded to a tropical storm by the National Hurricane Centre. Satellite imagery indicates that strong southwesterly wind shear has caused the center of Danny to become exposed. Intense squalls are only occurring in the northeastern quadrant with winds up to 50 mph. Gradual weakening is expected until Danny dissipates in about 60 hours between Puerto Rico and Hispaniola. Only minor impacts are expected for the islands of the northeastern Caribbean Sea.
Danny has officially been downgraded to a tropical storm by the National Hurricane Center (NHC). Tropical Storm Danny has been rapidly deteriorating on satellite imagery over the past 6 hours and currently maximum sustained winds are 65 mph. It is likely that Danny will weaken more quickly than previous forecast indicated. Danny will likely only be a weak tropical storm (at most) when it reaches the Leeward Islands.
Based on the 5am forecast today, Danny’s approximate Closest Point of Approach (CPA) is located near 18.0N, 64.6W or about 29.8 miles (47.9 km) south of Beef Island, Tortola, BVI. The estimated time the center of the storm is Tuesday, August 25 at 3:48AM AST. Hurricane force winds extend outward 15 miles from the centre while tropical storm force winds extend outward up to 60 miles. Tropical storm conditions are expected late Monday night through Tuesday morning. Sustained winds are expected to peak in the 40-55 mph range. Winds could potentially gust as high as 70 mph, especially for areas that are north of the centre. These winds are expected to cause widespread power outages.