Most of the cyclones tracked through the northwest subtropical Atlantic west of the 50th meridian to near the Eastern coast of the United States between mid-August and early October.

[5] A normal season, as defined by the National Oceanic and Atmospheric Administration (NOAA) in the period from 1981 to 2010, has approximately 12 named storms, with 6 of those reaching hurricane status.

[3] On July 23, 1983, forecasters at CSU predicted an above-average season in 1984 with a total of 11 tropical storms developing, 8 of which would reach hurricane status, under the assumption that sea-level pressures over the Caribbean Sea and Gulf of Mexico would be normal.

[5] Early in 1984, the Weather Research Center (WRC) forecast on the other hand called for a below-average season with seven named storms, with four of those strengthening into a hurricane.

[21][22] An upper-level low-pressure area traversing the southern Gulf of Mexico spawned convective activity over the Isthmus of Tehuantepec on June 16.

[20] The cyclone and its precursor dropped heavy rainfall in some areas, including a peak total of 11.43 in (290 mm) of precipitation in San Lucas Ojitlán, Oaxaca.

[25] The depression entered the Caribbean Sea and failed to intensify further, dissipating about halfway between the Dominican Republic and Venezuela late on July 26.

The history of Subtropical Storm One is not entirely certain, as satellite images were largely unavailable due to a failure of the VISSR unit on GOES EAST (then GOES-5), and this system remained at the fringe of the GOES WEST and Meteosat throughout its existence.

Moving westward and later northwestward, the system remained to the south of a persistent shearing pattern that inhibited the development of several tropical waves.

The cyclone attained its peak intensity several hours later with maximum sustained winds of 50 mph (85 km/h) and a minimum barometric pressure of 1,004 mbar (29.6 inHg).

Tracking westward, the wave developed into a tropical depression about 1,170 mi (1,885 km) west-southwest of the southwesternmost islands of Cape Verde and in close proximity to the east of Arthur.

[29] Later that day, Bertha peaked as a minimal tropical storm with maximum sustained winds of 40 mph (65 km/h) and a minimum barometric pressure of 1,007 mbar (29.7 inHg).

The system moved westward with no signs of development until September 1, when an upper-level low to its north across the Gulf of Mexico caused an area of thunderstorms to form just south of the Mexican coastline.

An upper trough developed across the southern Plains of the United States, which slowly lured the northern portion of this increasingly large disturbance northward through the Mexican Isthmus.

[30] By September 6, the disturbance had emerged into the southwest Gulf of Mexico and consolidated into a smaller system which had enough organization to be classified as a tropical depression, the seventh of the season.

Diana proved difficult for meteorologists to forecast, initially moving westward towards Cape Canaveral, but then turned to the north and paralleled the coastline.

Diana moved north-northeast, and performed a small anti-cyclonic loop before striking near Cape Fear, North Carolina, as a minimal Category 2 hurricane on September 13.

[20] Severe beach erosion impacted Horry County, South Carolina, damaging 90 residences, 40 multi-family dwellings, 8 mobile homes, and a few businesses.

As Fran passed the Cape Verde islands weather stations reported 35 miles per hour (55 km/h) winds, which is tropical depression force.

The newly-tropical storm quickly intensified while turning to the northwest, and late on September 25 Hortense attained hurricane status, about 300 miles (475 km) southeast of Bermuda.

[12] Twelve hours after reaching hurricane status, Hortense began a sharp weakening trend while passing east of Bermuda.

[12] Hortense accelerated to the northeast, moving rapidly across the north Atlantic before being absorbed by a larger extratropical storm late on October 2, northwest of the Azores.

[20] The hurricane caused wave damage to coastal areas, but primarily posed a threat to the shipping lanes of the North Atlantic.

The system tracked westward with limited shower and thunderstorm activity, crossing Florida on October 26 before moving into the Gulf of Mexico.

Once the system moved into the north-central Gulf, deep convection began to develop near its center, expanding in intensity and coverage near and after landfall in extreme southeast Mississippi.

After making landfall on extreme eastern Puerto Rico, it passed to the north of the Leeward Islands, resulting in strong southwesterly winds and rough seas.

Klaus attained hurricane status and reached peak winds of 90 miles per hour (145 km/h) before becoming extratropical over cooler waters on November 13.

Based on the observations, as well as the appearance of a well-defined eye, the NHC reclassified the storm as Hurricane Lili on December 20, estimating peak winds of 80 mph (130 km/h) and a pressure of 980 mbar (29 inHg).

However, Lili weakened due to increased wind shear, degrading to a tropical storm on December 23 while 430 miles (690 km) northeast of Antigua.

The storm rapidly lost organization as it approached the Leeward Islands, dissipating near the northern coast of the Dominican Republic on December 24.