1929 Florida Hurricane

The 1929 Bahamas hurricane (also known as the Great Andros Island Hurricane) was a high-end Category 4 tropical cyclone whose intensity and slow forward speed led to catastrophic damage in the Bahamas in September 1929, particularly on Andros and New Providence islands. Its erratic path and a lack of nearby weather observations made the hurricane difficult to locate and forecast. The storm later made two landfalls in Florida, killing eleven but causing comparatively light damage. Moisture from the storm led to extensive flooding over the Southeastern United States, particularly along the Savannah River. Across its path from the Bahamas to the mouth of the Saint Lawrence River, the hurricane killed 155 people.

The storm's origins can be traced to tropical wave first noted near the Cabo Verde Islands on September 11, 1929. This tropical disturbance remained dormant as it tracked west until September 18, when an associated area of thunderstorms developed into a tropical depression northeast of Puerto Rico. Gradually strengthening, the depression reached tropical storm strength on September 22 and hurricane strength on September 23. Beginning on September 24, the storm took a slow and southwestward path through the Bahamas, passing over Nassau and Andros Island between September 25–26 with maximum sustained winds of 145 mph (230 km/h). This southwestward trajectory was unprecedented for the islands. The storm then curved west and struck the Florida Keys at Key Largo on September 28 with winds of 115 mph (185 km/h). Two days later, the cyclone moved ashore Apalachicola, Florida, as a minimal hurricane shortly before transitioning into an extratropical cyclone. This system tracked northeast along the interior of the East Coast of the United States before dissipating near the Saint Lawrence River on October 4.

Poorly-built structures and ships were destroyed throughout the Bahamas. Andros Island was within the envelope of the storm's hurricane-force winds and storm surge for two days. Parts of the island were inundated by a surge that advanced inland, wiping out all crops and most fruit trees and livestock. A wind gust of was measured in Nassau, which also experienced the calm of the hurricane's eye for two hours. An estimated 73% of the city's homes and businesses sustained damage, leaving more than 5,000 people without homes. The hurricane was a heavy blow to the declining sponge industry on the islands. Following the storm, wild birds and crops were brought from the Caribbean to replenish their losses in the Bahamas. New building codes were enacted after the 1929 storm to prevent similarly extensive destruction.

A storm surge battered the Florida Keys, washing out highways and sinking small fishing boats. At least five tornadoes struck Florida, representing some of the first verified reports of tornadoes caused by a tropical cyclone. One impacted Fort Lauderdale's business center and caused $100,000 in damage. The Apalachicola waterfront sustained heavy damage from the storm's final landfall, including the loss of nearly all wharves. Widespread flooding occurred throughout Georgia and The Carolinas due to the continuous influx of moisture from the slowly-moving hurricane. A maximum rainfall total of was registered in Glennville, Georgia. The Savannah River reached a record stage of at Augusta, Georgia, breaching a levee and inundating much of the surrounding floodplain. The damage toll in the United States totaled to at least $9.31 million.

Background

The Lucayan Archipelago is especially vulnerable to tropical cyclones due to its position within the storm tracks of Atlantic hurricanes. Approximately 80% of its landmass has an elevation within of mean sea level. Before 1929, the islands were hit by hurricanes in 1866, 1899, and 1926 that each killed over a hundred people. The Bahamas, at the time a Crown colony, was adversely affected by the Great Depression. The economic downturn was further compounded by a sharp reduction in demand in the colony's sisal and sponge after World War I, a weak Pound sterling relative to the American dollar, and a severe drought in the central and southern islands. Hurricane warning systems in the Bahamas were mostly non-existent in 1929; islanders relied on personal weather instruments or the behavior of clouds, tides, and fauna to assess risk. District officers were responsible for informing others of a storm's approach based on the barometer housed in their homes. Flags signaling a hurricane's approach were present at Bahamian forts but were raised arbitrarily and inconsistently.

Meteorological history

The hurricane can be traced back to a complex of disturbed weather near Cabo Verde on September 11, producing showers across the open waters of the Atlantic and directed westward by the Azores High. The disturbance remained a weak tropical wave for much of its early history, but over time gradually organized. By September 15, weather maps began to notate the system as a trough of low pressure north of the Lesser Antilles. A portion of this trough split off and moved northwest towards the South Atlantic states while the remaining disturbance continued to organize, becoming a tropical depression approximately 355 mi (570 km) northeast of San Juan, Puerto Rico, by September 18. Over the next three days, the system remained a tropical depression as it tracked slowly west. It reached tropical storm strength by September 22 while northwest of San Juan and curved northwest. Continuing to strengthen, the storm reached hurricane intensity the following day. On September 24, the hurricane began to slowly move southwest towards the Bahamas, traversing the Northeast Providence Channel. Until that point, few observations probed the core of the hurricane on its approach of the islands due to its small size. In 2010, the Atlantic hurricane reanalysis project determined the storm had been rapidly intensifying during this period. On September 25, the steamship ''Potomac'' measured a central air pressure of 924 mbar (hPa; 27.30 inHg), suggesting wind speeds of 155 mph (250 km/h): a high-end on the Saffir–Simpson scale.

At 00:30 UTC on September 25, the intense hurricane passed over Nassau with sustained winds of 145 mph (230 km/h); the capital city was within the calm of the eye for two hours. The next day, the storm crossed Andros Island south of Fresh Creek, moving at , and afterwards curved slowly towards the west-northwest over the Florida Straits towards Florida. A high-pressure area associated with cool temperatures over the United States had been responsible for the sudden southwest trajectory over the Bahamas. The United States Weather Bureau remarked that the storm's track was "one of the most erratic and abnormal during the last 50 years", with both the slow movement and inadequate observations contributing in the agency's difficulty in locating the center of the storm. The hurricane's winds lessened while its size grew on its Florida approach, and on the morning of September 28, it crossed the Florida Keys near Tavernier, at the southern tip of Key Largo, with winds of 115 mph (185 km/h). A pressure of 948 mbar (hPa; 27.99 inHg) was estimated within a 10-minute lull near the eye's edge at Key Largo. Further weakening occurred as the hurricane accelerated northwestward into the eastern Gulf of Mexico, continuing this heading for two days. On September 30, the storm made an unexpectedly sharp turn towards the northeast, making landfall near Panama City, Florida, near midnight as a low-end hurricane with winds of 80 mph (130 km/h). Positioned near a steep temperature gradient, the storm quickly transitioned into an extratropical cyclone on October 1 shortly after landfall with cold air wrapping around the circulation. The extratropical cyclone quickly moved northeast across the Eastern Seaboard, eventually dissipating near the Saint Lawrence River by October 5.

Effects in the Bahamas

The 1929 hurricane brought catastrophic damage to parts of the Bahamas, killing 142 people. There, the storm has several monikers, including the "Storm of 1929" and the "Three-day Storm", among others. The storm's effects were exacerbated by the hurricane's slow motion, producing hurricane conditions for three days. Whereas the worst impacts of storms in the Bahamas were typically along coasts, the slow movement of the 1929 storm resulted in uniform destruction on both insular coasts and interiors. It was the first known instance of a storm approaching the islands from the northeast and the fifth hurricane overall to strike the island in three years. The unusual path placed Andros and New Providence islands within the strongest quadrant of the storm; the hurricane passed over these islands with an intensity equivalent to a Category 4 hurricane on the modern Saffir–Simpson scale. The swath of winds exceeding 100 mph (160 km/h) cut through much of the Bahamas, encompassing the entirety of Andros and New Providence islands and parts of Great Abaco Island and the Berry Islands.

The weaker construction standards of the era succumbed to the force of the hurricane. Poorly-built structures were destroyed en masse by the storm. Many ships throughout the Bahamas were driven ashore and destroyed. The sponging industry, at the time the colony's most prominent economic activity, was badly affected; nearly all sponge warehouses and roughly 70% of sponge vessels were destroyed, with many other ships sustaining serious damage. Communication was lost between many of the islands in the Bahamas. Only a few radio stations remained in the Out Islands, with limited capacity for international communications. Crops sustained widespread losses and roads required significant repairs.

Andros and New Providence experienced the heaviest blow in the Bahamas. Other islands in the Bahamas sustained lesser impacts as the force of winds was diminished farther out from the center of the storm. Great Abaco Island endured hurricane-force winds of up to 100 mph (160 km/h) for 36 hours, causing "minor to major damage". Nineteen homes and twelve boats were wrecked on the island. The steamship ''Wisconsin Bridge'' went aground along the southeastern tip of Abaco Island near the Hole-in-the-Wall lighthouse; all but one of the 34 crew chose not to evacuate, and those that did perished. The lighthouse was also damaged by the storm. The British freighter ''Domira'' went aground off Great Abaco on September 25. A colonial lighthouse tender was designated to render assistance but could not depart promptly due to the rough seas. Minor damage was also reported on Eleuthera and Cat Island. Communications on Eleuthera were disrupted after winds reached 50 mph (80 km/h).
p. 1p. 9
/ref> Strong but mostly non-damaging gale-force winds and squalls were reported in Grand Bahama, Great Exuma Island, Long Island, and Ragged Island; one schoolhouse collapsed in Ragged Island.

Andros Island

Andros Island experienced its worst storm in at least a century, with the entire island thoroughly devastated. At least 25 fatalities occurred on the island. As the storm's center progressed from the Tongue of the Ocean towards the west of the Bahamas, Andros Island endured hurricane-force winds and rough seas for nearly 48 hours. The onslaught was prolonged by the storm's slow motion— when it moved across Andros Island on September 26—and its expansion as it approached the island; the diameter of the region of hurricane-force winds expanded from upon the storm's initial entrance into the Northeast Providence Channel to atop Andros Island. A storm surge higher than swamped the island from Mangrove Cay southward, the winds driving the sea inland along the western and southern coasts of Andros Island and raking the land clear of vegetation. According to the annual report for the island submitted to the Bahamas House of Assembly, all crops and most fruit trees, livestock, and poultry on Andros Island perished. In some locations, the inundation was deep. Areas of the island farther north experienced less flooding. Several ships were lost in the storm at Andros Island. The British tanker ''Potomac'', sailing from Havana, Cuba