Tropical Storm Arthur (2002)

Map plotting the storm's track and intensity, according to the Saffir–Simpson scale

Map key

Saffir–Simpson scale

  Tropical depression (≤38 mph, ≤62 km/h)
  Tropical storm (39–73 mph, 63–118 km/h)
  Category 1 (74–95 mph, 119–153 km/h)
  Category 2 (96–110 mph, 154–177 km/h)
  Category 3 (111–129 mph, 178–208 km/h)
  Category 4 (130–156 mph, 209–251 km/h)
  Category 5 (≥157 mph, ≥252 km/h)
  Unknown

Storm type

Tropical cyclone

Subtropical cyclone

Extratropical cyclone, remnant low, tropical disturbance, or monsoon depression

The origins of Tropical Storm Arthur are believed to have been from a decaying cold front in the northeastern Gulf of Mexico in July 2002. By July 9, a weak low-level circulation was first detected,[1] in association with a broad low pressure area. Across the region, surface pressures were high, while upper level wind shear was marginally favorable for slow tropical development.[2] The system tracked slowly north-northwestward, gradually becoming better defined, although thunderstorm activity remained limited and disorganized.[3]

By July 11, dry air and unfavorable wind shear prevented the convection from developing near the center.[4] The low became elongated, though on July 12 the overall convection became more concentrated as it turned to a northeast drift.[5] An approaching mid-level trough caused the system to accelerate northeastward across Florida Panhandle,[1] though upon doing so the thunderstorm activity quickly diminished. On July 13, forecasters expected the system to be absorbed by the approaching trough.[6] However, the low pressure area emerged into the western Atlantic Ocean near North Carolina early on July 14, and upon doing so its convection increased and became better organized.[7] The circulation and convection became further defined, and the National Hurricane Center estimates the system developed into Tropical Depression One late on July 14 about 45 miles (72 km) west-southwest of Hatteras, North Carolina.[1]

Upon becoming a tropical cyclone, the depression was moving quickly to the east-northeast, due to a deepening mid-level low south of the Canadian Maritimes. It maintained good upper-level outflow, and its track over the gulf stream allowed for steady strengthening.[8] Early on July 15, convection increased over the center and developed an organized rainband southwest of the center;[9] as a result, the National Hurricane Center upgraded the depression to Tropical Storm Arthur. After continuing to steadily intensify, Arthur attained peak winds of 60 mph (97 km/h) early on July 16 about 490 miles (790 km) south-southeast of Halifax, Nova Scotia.[1] Upon reaching peak intensity, the convection had become well-organized over the center despite westerly wind shear.[10] Subsequently, the center became separated from the area of deepest convection,[11] and Arthur maintained its peak intensity as it began transitioning into an extratropical cyclone. The storm turned northward around the larger mid-level low, and by July 17 Arthur completed extratropical transition. Shortly thereafter, the extratropical remnants crossed eastern Newfoundland. On July 19, the remnants of Arthur turned to a southeast drift between Newfoundland and Greenland, and by late in the day its winds decreased to below gale force.[1]

Rainfall Summary for Tropical Storm Arthur

The precursor tropical disturbance dropped light to moderate precipitation in Florida, Georgia, and South Carolina,[1] peaking at 4.49 inches (114 mm) in Weston, Florida. The system produced scattered precipitation across North Carolina, generally between 1–3 inches (25–76 millimetres).[12] On July 16, Arthur passed north of Bermuda, where it brought gusty winds and 0.57 inches (14 mm) of rainfall.[13] As an extratropical storm, Arthur produced gusty winds and dropped about 1 inch (25 mm) of rainfall in Newfoundland.[1] Strong waves capsized a boat in the Conne River, killing one person.[14]

Five ships recorded tropical storm force winds in association with Arthur, of which two were when the storm was extratropical. Early on July 16, a vessel with the call sign Weston reported sustained winds of 51 mph (82 km/h) from the south-southwest, which was the strongest ship reported wind speed. As the storm approached Canada as an extratropical storm, a buoy reported an 8-minute average wind speed of 45 mph (72 km/h), along with a wind gust of 60 mph (97 km/h).[1]

• List of North Carolina hurricanes (2000-present)
• List of Florida hurricanes (2000-present)
• Other tropical cyclones named Arthur