Hurricane Bonnie was a tropical cyclone that made landfall in North Carolina, inflicting severe crop damage. The second named storm, first hurricane, and first major hurricane of the 1998 Atlantic hurricane season, Bonnie developed from a tropical wave that emerged off the coast of Africa on August 14. The wave gradually developed, and the system was designated a tropical depression on August 19. The depression began tracking towards the west-northwest, and became a tropical storm the next day. On August 22, Bonnie was upgraded to a hurricane, with a well-defined eye. The storm peaked as a Category 3 hurricane on the Saffir-Simpson Hurricane Scale, and around the same time, the storm slowed and turned more towards the north-northwest. A large and powerful cyclone, Bonnie moved ashore in North Carolina early on August 27, slowing as it turned northeast. After briefly losing hurricane status, the storm moved offshore and regained Category 1-force winds, although it weakened again on entering cooler waters.
Fearing a major hurricane strike, coastal locations from Florida to Virginia performed extensive preparations in advance of the storm. In addition to tropical cyclone watches and warnings, about 950,000 people were evacuated from the Carolinas, and the military evacuated and relocated hundreds of aircraft and vessels from the storm's projected path. Soldiers and guardsmen were deployed throughout those regions.
Hurricane Bonnie made landfall as a borderline Category 2–Category 3 storm, with intense wind gusts of up to and rainfall peaking at about . Reports of downed trees and powerlines, as well as structural damage such as blown-out windows and torn-off roofs, were reported. In coastal North Carolina, the storm washed ashore tens of thousands of tires that had been part of an artificial reef. Crop damage was extensive, but the storm was overall less severe than initially feared. Total damage was estimated at $1 billion (1998 USD).
Meteorological history
On August 14, 1998, a tropical wave emerged off the west coast of Africa just north of Dakar and moved westward across the Atlantic Ocean. Initially located within cool waters, a strong high pressure area steered the disturbance on a west-southwest track over warmer waters, and convection started to develop. Several small centers of rotation existed within a broad circulation, and at 1200 UTC on August 19, the centers consolidated and the disturbance became sufficiently organized to be declared a tropical depression. Despite being poorly organized, winds slightly to the north of the system's center approached tropical storm strength shortly thereafter. Ship reports revealed a closed circulation, though the center was elongated in a northwest–southeast oriented manner. Upper-level winds were favorable, which suggested that intensification was likely. The cyclone began moving on a northwestward track, and just hours later the center of circulation appeared to reform close to the convection, an indication of a strengthening storm, as good outflow existed over the western side of the storm. Deep convection slowly developed closer to the center, and at 1200 UTC on August 20, the depression was upgraded into Tropical Storm Bonnie as it continued its west-northwest track around the periphery of a high pressure system over the Leeward Islands.
Late on August 20, the first reconnaissance plane entered the storm and found a minimum central barometric pressure of 1001 mb. The storm brushed the Leeward Islands, although the main thunderstorm activity remained to the north of the storm over the open ocean. Bonnie began to organize its broad circulation early on August 21, and within the next day the storm began to intensify. The storm began to look strong on satellite images with banding features over the north and west quadrants. The Hurricane Hunters aircraft found a minimum pressure of 987 mb and a nearly complete eyewall early on August 22, and as a result, the tropical storm was upgraded to hurricane status. Bonnie slowed in forward speed, coinciding with previous forecasts. Later that day, storm was upgraded to a Category 2 on the Saffir-Simpson Hurricane Scale, which occurred with a substantial 15 mb drop in 8 hours. At the same time, steering currents weakened with the dissipation of the high pressure system; this, combined with the effect of a nearby trough, caused the storm to turn in a more north-northwestward direction around the western periphery of an anticyclone to the east. Bonnie became a Category 3 storm, a major hurricane, at 1200 UTC the next day, reaching its peak winds of at the same time.
A mid- to upper-level trough slowed the storm almost to a halt early on August 23, before a drift to the north-northwest began. The next National Hurricane Center (NHC) advisory then reported that the eye was becoming more distinct and well-defined. This strengthening trend abated because the storm had churned up the waters over which it was passing, bringing cooler water to the surface as a result of the slow track. Another inhibiting factor may have been related to the same trough that caused the northward turn, though due to a large anticyclone situated over the hurricane, the weakening effects were not substantial. Despite wind shear, the large and powerful circulation resisted weakening for a time. Early on August 25, the shear and the entrainment of drier air into the hurricane took its toll on Bonnie, giving it a ragged appearance on satellite imagery, and the eye briefly became cloud-filled.
The storm accelerated somewhat by August 26, and early that day, it was moving at about . An approaching mid-level trough steered Bonnie north-northeast, and at 2100 UTC on August 26, the eye passed east of Cape Fear, North Carolina. The hurricane once again slowed, and early the next day, it made landfall near Wilmington, North Carolina, as a strong Category 2 hurricane. Doppler weather radar displays estimated that maximum sustained winds had quickly weakened to below hurricane intensity, and the storm was briefly downgraded to a tropical storm. However, as the storm turned towards the east in response to the approaching trough, the center neared open waters and the winds began to re-intensify. As a result, the cyclone re-attained hurricane status at 0000 UTC on August 28. Offshore, the center began drifting roughly eastward. Entering colder waters, hurricane status was lost at 1800 UTC that day, followed by an acceleration to the northeast. The storm began to lose deep thunderstorm activity, and was forecast to lose tropical characteristics and become an extratropical cyclone within days. By early on August 29, little connection remained over the western semicircle, and only a band of such activity persisted to the southeast of the center. Bonnie became extratropical around 1800 UTC on August 30, to the southeast of Newfoundland.
Preparations On August 20, a tropical storm watch was posted for the islands of Antigua, Barbuda, Anguilla, St. Maarten, Saba and St. Eustatius, though it was discontinued the next day. Shortly thereafter, a tropical storm warning was issued for the U.S. and British Virgin Islands. Tropical storm warnings and hurricane watches were put into effect for the Turks and Caicos Islands and the southeastern Bahamas. By August 24, those tropical cyclone advisories were discontinued, and at the same time they were issued for parts of the Southeast United States. A hurricane warning was eventually posted for Murrells Inlet, South Carolina to the North Carolina – Virginia border. On August 27, tropical cyclone watches and warnings extended as far north as Plymouth, Massachusetts; all were discontinued early on August 29.
Florida and South Carolina
Initially the storm posed a threat to Florida, where military officials kept abreast of the situation. Heavy surf advisories were posted from central portions of the state northward to Georgia, and the National Hurricane Center advised that swimming and boating should be avoided. The Mayport Naval Station ordered 25 ships out to sea in advance of the approaching storm. The Salvation Army was on standby in Jacksonville, prepared to act when needed. Hardware stores in the state reported up to a 75% increase in the sales of emergency supplies.
Some computer forecast models initially predicted that the storm would move towards South Carolina or Georgia. Before the storm's arrival in South Carolina, researchers at Clemson University used Bonnie to test a new method of estimating the damage a storm is likely to cause. In the state, the South Carolina National Guard put about 1,512 men on active duty, 1,474 being of the Army National Guard. On August 25, the South Carolina Emergency Preparedness Division activated Level 1 operations, the highest of five levels. That same day, the State Governor declared a State of Emergency, calling for mandatory evacuations of residents east of U.S. Route 17 in Horry and Georgetown counties. Schools were closed throughout the state. Over 200,000 people were evacuated from those counties, of which 120,000 were tourists. About 6,000 sought shelter at schools in Horry County. In a survey, 12% of respondents in the state took traffic as a significant consideration in deciding if they should evacuate. On the Grand Strand, Bonnie was the first storm where buses were provided to help people evacuate.
North Carolina and Virginia
About 815 guardsmen were called to North Carolina, where they assisted local authorities with the extensive preparations, including evacuating 750,000 state citizens. Mandatory and voluntary evacuations were ordered for part of the state. The Outer Banks experienced extensive evacuations; at least 300,000 left, bringing traffic on highways from there to the mainland to a standstill. Active duty armed forces were set to support hurricane recovery missions, and four Defense Coordinating officers were notified. Defense Department emergency centers were opened starting August 21. Additionally, the U.S. Atlantic Command activated their 24-hour response cell. Soldiers, sailors, airmen, and Marines evacuated equipment, including hundreds of vessels and aircraft. The North Carolina Department of Environment and Natural Resources closed several state parks, all three state aquariums, and the Division of Marine Fisheries office, with plans to reopen primarily once storm-related damage at any of the locations was properly addressed.
A study was performed on the storm in eight counties in North Carolina to determine the cost of evacuation for hurricanes, and included 1,029 households. Another study was performed regarding the actions taken during Hurricane Bonnie evacuations in the state. Tourists were interviewed, and it was found that 90% of vacationers who were threatened by the hurricane evacuated, of which 56% went home, 3% stayed in public shelters, 22% stayed with friends or relatives, 3% stayed in hotels and motels, and 16% stayed elsewhere. In total, 58% stayed within North Carolina, 12% went to Virginia, 6% relocated to South Carolina, and 24% stayed in other regions. Most of the evacuees left on August 25; 80% left with their own vehicles, and 18% used rental transportation. Officials in the state opened an estimated 100 shelters to accommodate the evacuating tourists and residents.