BULLETIN Tropical Storm Sam Advisory Number 4 NWS National Hurricane Center Miami FL AL182021 1100 AM AST Thu Sep 23 2021 ...DEPRESSION STRENGTHENS INTO TROPICAL STORM SAM, THE 18TH NAMED STORM OF THE SEASON... ...NOW FORECAST TO BECOME A HURRICANE TOMORROW... SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION ----------------------------------------------- LOCATION...10.9N 38.1W ABOUT 1745 MI...2805 KM ESE OF THE NORTHERN LEEWARD ISLANDS MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H PRESENT MOVEMENT...W OR 280 DEGREES AT 16 MPH...26 KM/H MINIMUM CENTRAL PRESSURE...1003 MB...29.62 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 1100 AM AST (1500 UTC), the center of Tropical Storm Sam was located near latitude 10.9 North, longitude 38.1 West. Sam is moving toward the west near 16 mph (26 km/h) and this general motion is expected to continue over the next several days, but with a gradual slowdown in forward motion. Recent sallite wind data indicates maximum sustained winds have increased to near 50 mph (85 km/h) with higher gusts. Additional strengthening is forecast over the next several days, and Sam is now forecast to become a hurricane tomorrow and be near major hurricane intensity by the end of the weekend. Tropical-storm-force winds extend outward up to 45 miles (75 km) from the center. The estimated minimum central pressure is 1003 mb (29.62 inches). HAZARDS AFFECTING LAND ---------------------- None.