The 1938 Atlantic hurricane season produced fifteen tropical cyclones, of which nine strengthened into tropical storms. Four storms intensified into hurricanes. Two of those four became major hurricanes, the equivalent of a Category 3 or greater storm on the modern day Saffir–Simpson scale. The hurricane season officially began on June 16 and ended on November 15. In 2012, as part of the Atlantic hurricane reanalysis project, meteorologists identified a previously undocumented January hurricane and September tropical storm while fine-tuning the meteorological histories of several others. However, given scant observations from ships and weather stations, significant uncertainty of tropical cyclone tracks, intensity, and duration remains, particularly for those storms that stayed at sea.

Seasonal activity began with the formation of a tropical or subtropical cyclone over the northeastern Atlantic on January 3, the earliest occurrence in a calendar year (earliest start to a season) on record. In mid-August, a hurricane struck near Cameron, Louisiana, producing strong winds and water level rises that caused $245,550 in damage throughout that state and Texas. It was followed in quick succession by an even more potent hurricane that tracked through the Caribbean, Gulf of Mexico, and into northern Mexico. There, 9 people were killed and over 400 families were left homeless. An additional 4 deaths occurred in Texas. The season's strongest and most destructive system, the "Great New England Hurricane", swept into New England, where 494–700 people were killed, over 1,700 individuals were injured, and about 23,900 structures were damaged or destroyed. The cost was estimated at $620 million. It was the strongest hurricane to hit New England in over 300 years, since 1635. Later in the season, a minimal mid-October tropical storm affected Texas and Louisiana, and a stronger early-November tropical storm caused minor damage along the eastern coastline of Florida.

The season's activity was reflected with an accumulated cyclone energy (ACE) rating of 78 units, below the 1931–1943 average of 91.2. ACE is a metric used to express the energy used by a tropical cyclone during its lifetime. Therefore, a storm with a longer duration will have high values of ACE. It is only calculated at six-hour increments in which specific tropical and subtropical systems are either at or above sustained wind speeds of , which is the threshold for tropical storm intensity. Thus, tropical depressions are not included here.

Timeline

Systems Hurricane One

In 2012, as part of their ongoing Atlantic hurricane reanalysis project, the National Hurricane Center identified a previously undocumented hurricane. On January 1, an extratropical cyclone formed over the northeastern Atlantic along the tail-end of a cold front. The cyclone initially moved east but soon turned south then west by January 3. Warm air coalesced in the vicinity of the storm, and the frontal boundary dissipated, leading to the formation of a tropical storm by 18:00 UTC on January 3 about southwest of the Azores. It is possible, however, that the system existed as a subtropical cyclone before transitioning into a fully tropical entity. The storm temporarily embarked on a more westerly course before banking south-southwest, through which time it intensified into a Category 1 hurricane, peaking with winds of . Gradual weakening ensued as the cyclone entered the deep tropical Atlantic east of the Leeward Islands, with its final point recognized at 18:00 UTC on January 6.

The cyclone is one of only two hurricanes to form in the Atlantic basin during the month of January, alongside Hurricane Alex in 2016. Hurricane Alice attained hurricane strength in January 1955 but developed the previous month. Additionally, it is one of only seven tropical or subtropical cyclones to persist during the month, including the aforementioned systems, a tropical storm in 1951, a subtropical storm in 1978, Tropical Storm Zeta in 2006, and a subtropical storm in 2023.

Tropical Storm Two

A strong tropical storm with peak winds of was first identified just west of Antigua and Barbuda at 06:00 UTC on August 8, though it may have developed days earlier in the absence of a reliable data network. The rapidly-moving system curved west, passing north of Puerto Rico before striking the northeastern coastline of the Dominican Republic as a cyclone at 09:00 UTC on August 9. The storm continued across Hispaniola and dissipated after 18:00 UTC that day, though the remnant tropical wave continued on to impact Cuba on August 10.

Hurricane Three

Around 00:00 UTC on August 10, a rapidly-moving tropical storm was identified southeast of Barbados. It tracked into the Caribbean Sea and intensified into the season's second hurricane, with the center of the storm narrowly missing Jamaica to the north late on August 11. Observations from Grand Cayman indicate that it strengthened into a Category 2 hurricane, reaching peak winds of that day, before the system slowly weakened. It moved through the Yucatán Channel and into the Gulf of Mexico, making a later landfall just west of Cameron, Louisiana, at 01:00 UTC on August 15 with winds of . The cyclone curved north-northeast and was last observed as a weak tropical depression along the Arkansas–Louisiana border at 12:00 UTC on August 15.

Along the northern fringes of Jamaica, appreciable loss to cultivation occurred. Winds at nearby Grand Cayman topped at , destroying nine houses and injuring several people. In the United States, sustained winds southeast of Lake Charles, Louisiana, reached and gusts peaked around . There, windows were blown from the city hall and upper floor of several downtown structures. Small vessels were overturned, and the downing of trees and signs obstructed highways. A grandstand and fence at the American Legion ballpark were smashed, as well as two planes at the Lake Charles Regional Airport. Hurricane-force winds were estimated in nearby Grand Chenier. Squalls caused damage to structures in Benton and overturned a boat on Cross Lake, causing a man to drown. Another man was found drowned on the western edge of the Calcasieu River. Five people were rescued from their motor boat on Lake Pontchartrain. A small tornado moved through Kinder, causing $2,000 in damage after it destroyed a house and toppled two barns, fencing, and some trees. Throughout the state, the winds caused damage to buildings, wires, oil derricks, piers, and other structures totaling to $133,000. Water levels of above the mean low tide inundated the coasts of Cameron and Vermillion parishes, and lowlands were flooded to a depth of . Shrimp boats were beached near Creole, and the Intracoastal Ferry—carrying four cars amounting to 20 people—broke its cable, crashing onto a river bank. Torrential rainfall, peaking at in Koll, caused extensive damage to crops; the rice, cotton, and corn crops in particular were heavily affected, with total damage estimated at $110,000. Several cities saw 24-hour rainfall records. Considerable damage to highways was also noted, with detours or interruption to traffic for east of the center, particularly in Jefferson Davis Parish. In Texas, damage was confined to the Sabine Pass area, where the cost to piers and highways reached $550. Communications between Port Arthur and Galveston were severed.

Hurricane Four

A tropical storm first developed to the south of Haiti by 06:00 UTC on August 23 and moved west-northwest, a trajectory it maintained throughout its duration. The system intensified into a hurricane shortly after passing south of Jamaica and Grand Cayman on August 24. As it passed south of Cozumel, the island recorded winds of . The storm reached its peak as a Category 3 hurricane with winds of around 02:00 UTC on August 26, while making landfall along the Yucatán Peninsula. It weakened to Category 1 intensity as it crossed land and emerged into the southern Gulf of Mexico, later moving ashore the coast of Tamaulipas with winds of at 08:00 UTC on August 28. It is possible the storm could have been stronger given the size of the storm surge farther north in southern Texas. The cyclone curved west after tracking inland and became a remnant low after 00:00 UTC on August 29.

Thousands of banana trees were destroyed by winds across six districts in Jamaica; this accounted for roughly 5% of the island's crop, though some areas locally saw losses as high as 20%. In Portland, Jamaica, hundreds of banana and breadfruit trees were blown down in a 15-minute period. Considerable property damage was also wrought on the island, marked by the loss of some homes and the unroofing of others. Roads were blocked by landslides triggered by heavy rains. Shipping and airmail services were disrupted as ships and planes were held during the storm's passage. Telegraph communications were also subject to disruptions as the storm passed. Winds reached on Grand Cayman on the night of August 24. Communications with Cozumel were lost late on August 25, before the onset of the worst conditions. High winds toppled numerous trees and destroyed at least 200 homes. However, the overall damage toll on the Yucatán Peninsula was lessened by the relatively low population density of the peninsula's northeastern coast.

After the hurricane struck the coastline of northern Mexico, local observers reported a swath of damage along the beach in La Pesca. Palm-thatched huts were badly damaged or collapsed. Further inland, up to of rain in a few hours caused creeks and rivers, particularly the Rio Grande, to rapidly rise. Waters rose over to their highest level in six years, over-spilling into farmlands near Matamoros, Tamaulipas after a levee was breached and inundating multiple areas on the Mexican side of the United States–Mexico border near McAllen, Texas. Nine people were killed, including eight who were swept away by floodwaters and one whose body was recovered from a home ravaged by wind and floodwater. The vehicles of several American tourists were engulfed by the Santa Catarina River on the road between Mexico City and Ciudad Victoria. The latter city was isolated from the remainder of Mexico. More than 400 families were left homeless. The military and local officials transformed public buildings into temporary shelters. In Texas, squalls produced winds estimated up to . A sizable storm surge swept across Padre Island and Brazos Island and washed away a few inexpensive structures in Del Mar Heights. Rainfall across the extreme southern sections of the state was received as beneficial to dry crops. However, this rain exacerbated floodwaters within the river to breach a levee in Cameron County, where two people were drowned and swept away in Los Indios. Three more people died near El Paso in an attempted river crossing. Farther west in Albuquerque, New Mexico, rainfall totaling eroded unpaved side roads and inundated the basements of homes and stores.

Tropical Storm Five

A tropical wave moved off the western coast of Africa around September 4 and moved westward, spawning a tropical depression about east of Barbados by 12:00 UTC on September 9. The newly formed cyclone tracked west-northwest and maintained tropical depression intensity for several days. By 00:00 UTC on September 13, data from nearby ships was sufficient to upgrade it to a tropical storm with peak winds of . The system curved poleward and weakened while interacting with a broad trough or area of low pressure. Its final point has been analyzed a few hundred miles north of Puerto Rico after 00:00 UTC on September 14. This system was discovered the during the Atlantic reanalysis project in 2012.

Hurricane Six