1. A Tropical Storm Warning is in effect for a portion of the North Carolina coast. Tropical-storm-force winds and heavy rains are expected there today.

2. Dangerous coastal surf conditions and rip currents are expected to spread northward along the southeast U.S. coast to the mid-Atlantic states during the next couple of days. See products from your local National Weather Service Forecast Office for more details.

WHAT'S NEW:

None.

SUMMARY OF ALERTS:

A Tropical Storm Warning is in effect for...
- Surf City to Duck NC
- Pamlico and Albemarle Sounds

A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area. For storm information specific to your area, including possible inland watches and warnings, please monitor products issued by your local National Weather Service forecast office.

WIND: [TOP] Tropical storm conditions are expected within the Tropical Storm Warning area through early afternoon. RAINFALL: [TOP] Arthur is expected to produce total rain accumulations of 1 to 3 inches over coastal North Carolina through this afternoon, with isolated maximum amounts of 5 inches. SURF: [TOP] Swells generated by Arthur are affecting portions of the southeast U.S. coast and are expected to spread northward along the U.S. mid-Atlantic coast during the next day or so. These swells could cause life-threatening surf and rip current conditions. Please consult products from your local weather office.

At 1100 AM EDT (1500 UTC), the center of Tropical Storm Arthur was located near latitude 35.1 North, longitude 75.2 West. Arthur is moving toward the north-northeast near 16 mph (26 km/h). A turn toward the northeast is expected later today, followed by a turn toward the east on Tuesday. A slower southeast or south-southeast motion is forecast to begin Tuesday night and continue through Wednesday. On the forecast track, the center of Arthur will begin moving away from the North Carolina Outer Banks this afternoon. Arthur is then forecast to turn away from the east coast of the United States tonight and Tuesday. Reports from an Air Force Reserve reconnaissance aircraft indicate that the maximum sustained winds are near 50 mph (85 km/h) with higher gusts. Some additional strengthening is forecast during the next 24 hours. Little change in strength is expected Tuesday night and Wednesday. Tropical-storm-force winds extend outward up to 125 miles (205 km) from the center, primarily over water to the east of the center. NOAA buoy 41025 located about 20 miles (30 km) southeast of Cape Hatteras, North Carolina, reported sustained winds of 43 mph (68 km/h) with a gust to 49 mph (80 km/h). The latest minimum central pressure estimated from reconnaissance aircraft data is 996 mb (29.42 inches).

Arthur has become a little better organized this morning with an overall increase in convection and banding noted since overnight. The first couple of reconnaissance aircraft passes through the center have shown that the pressure has fallen to around 996 mb. The plane has also reported several believable SFMR winds of 38-43 kt, and the anemometer on buoy 41025 at an elevation of only 4 m has reported a peak 1-minute wind of 37 kt. Based on these data the initial intensity is set at 45 kt.

The forward speed of Arthur has continued to increase and the estimated motion is north-northeast at 14 kt. The cyclone should turn northeastward later today and begin moving away from the North Carolina Outer Banks as a mid-latitude trough approaches from the west. By Tuesday, Arthur is forecast to turn eastward within the mid-latitude westerlies. After that time, a deepening trough over the central and western Atlantic is expected to cause the cyclone to turn southeastward as the steering flow turns northwestward. The GFS and ECMWF are now in relatively good agreement on this scenario and the new NHC track forecast lies between those typically reliable models and the multi-model consensus aids.

Although the vertical shear is increasing over the storm and it is soon moving over cooler waters, some strengthening due to baroclinic process is predicted over the next 24 hours. The storm should merge with a frontal boundary late tonight or early Tuesday which will complete Arthur's transition to an extratropical cyclone. By Wednesday, the post-tropical cyclone should begin to weaken as the frontal gradients decrease. The post-tropical cyclone should dissipate in about 96 h.