Tropical Storm Ernesto formed east of the Leeward Islands on Monday afternoon.  At 5:00 p.m. EDT on Monday the center of Tropical Storm Ernesto was located at latitude 16.0°N and longitude 57.5°W which put the center about 295 miles (475 km) east-southeast of Antigua.  Ernesto was moving toward the west-northwest at 28 m.p.h. (44 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h).  The minimum surface pressure was 1009 mb.

Tropical Storm Warnings were in effect for Guadeloupe, St. Martin, St. Barthelemy, St, Kitts, Nevis, Montserrat, Antigua, Barbuda, Anguilla, Saba, St. Eustatius, Sint Maarten, the British Virgin Islands, the U.S. Virgin Islands, Puerto Rico, Culebra, Vieques.

A U.S. Air Force Reserve Hurricane Hunter aircraft found a distinct low level center of circulation in a tropical wave previously designated as Potential Tropical Cyclone Five, and the U.S. National Hurricane Center designated the system as Tropical Storm Ernesto.

More thunderstorms formed near the center of Tropical Storm Ernesto.  Bands of showers and thunderstorms began to revolve around the center of Ernesto’s circulation.  Storms near the center of Ernesto started to generate upper level divergence that pumped mass away from the tropical storm.

The reconnaissance plane also found that tropical storm force winds extended out 60 miles (95 km) in the northeastern quadrant of Tropical Storm Ernesto.  The winds in the other parts of Ernesto’s circulation were blowing at less than tropical storm force.

Tropical Storm Ernesto will move through an environment somewhat favorable for intensification during the next 24 hours.  Ernesto will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the southern part of an upper level ridge over the subtropical Atlantic Ocean.  The ridge will produce strong easterly winds that will blow toward the top of the tropical wave.  Those winds will cause moderate vertical wind shear.  The wind shear will inhibit intensification, but the shear is not enough to stop intensification. Tropical Storm Ernesto is likely to intensify gradually during the next 24 hours.

Tropical Storm Ernesto will move around the southern side of a subtropical high pressure system over the Atlantic Ocean.  The high pressure system will steer the tropical wave quickly toward the west-northwest during the next 24 hours.  On its anticipated track, ‘Tropical Storm Ernesto could reach the Leeward Islands early on Tuesday.  Ernesto could be near Puerto Rico on Tuesday night.

Tropical Storm Ernesto will bring gusty winds and locally heavy rain to the Leeward Islands, the British Virgin Islands, the U.S. Virgin Islands and Puerto Rico.  Heavy rain is likely to cause flash floods in some locations.  The winds could be strong enough to cause localized outages of electricity.  Ernesto could also cause a storm surge of up to 4 feet (1 meter).