Hurricane Erin rapidly intensified to Category 4 on the Saffir-Simpson Scale on Saturday morning. At 8:00 a.m. EDT on Saturday the center of Hurricane Erin was located at latitude 19.6°N and longitude 62.0°W which put the center about 120 miles (195 km) northeast of Anguilla. Erin was moving toward the west-northwest at 20 m.p.h. (32 km/h). The maximum sustained wind speed was 145 m.p.h. (235 km/h) and there were wind gusts to 175 m.p.h. (280 km/h). The minimum surface pressure was 935 mb.
Tropical Storm Watches are in effect for St. Martin, St. Barthelemy, and Sint Maarten.
Hurricane Erin rapidly intensified to a Category 4 hurricane on the Saffir-Simpson Scale early on Saturday morning. A circular eye with a diameter of 12 miles (19 km) was at the center of Erin’s circulation. A ring of thunderstorms surrounded the eye and the strongest winds winds occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the center of Hurricane Erin. Storms near the center of Erin generated strong upper level divergence that pumped large quantities of mass away from the hurricane. The removal of large amounts of mass caused the surface pressure to decrease rapidly.
The circulation around Hurricane Erin is small. Winds to hurricane force extend out 30 miles (50 km) from the center of Erin’s circulation. Winds to tropical storm force extend out 130 miles (210 km) in the northern side of Hurricane Erin. Winds to tropical storm force extend out 60 miles in the southern half of Erin’s circulation.
The Hurricane Intensity Index (HII) is 29.9. The Hurricane Size Index (HSI) is 8.4 and the Hurricane Wind Intensity Size Index (HWISI) is 38.3. Hurricane Erin is similar in size and intensity to Hurricane Charley in 2004.
Hurricane Erin will move through an environment that will be very favorable for intensification during the next 24 hours. Erin will move over water where the Sea Surface Temperatures are near 29°C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Hurricane Erin will intensity during the next 24 hours. Erin could strengthen to Category 5 on the Saffir-Simpson Scale.
Hurricane Erin will move around the southern side of a high pressure system over the Atlantic Ocean. The high pressure system will steer Erin toward the west-northwest during the next 24 hours. On its anticipated track, the center of Hurricane Storm Erin will pass north of the Puerto Rico on Sunday.
Bands in the southern side of Hurricane Erin are likely to bring gusty winds and locally heavy rain to the Northern Leeward Islands. Heavy rain could cause flash floods in some locations. Bands feeding into the southern side of Hurricane Erin could also drop heavy rain on Puerto Rico.
A Flood Watch is in effect for Puerto Rico.
