From Africa to the Pacific: Tropical Storm Greg's Quiet 5,000-Mile Journey
Tropical Storm Greg formed in the eastern Pacific on 14 August 2023 after a tropical wave moved from Africa across the Atlantic, the Caribbean region, and Central America. The storm crossed into the central Pacific while remaining over open water and produced no fatalities, damage, or coastal impacts. Greg reached peak intensity with maximum sustained winds of 55 kt (63 mph) from 1800 UTC on 15 August to 1200 UTC on 16 August. The cyclone dissipated on 18 August 2023 after tracking through remote Pacific waters without affecting the U.S. Gulf Coast, Caribbean islands, Mexico, or Hawaii.
African Wave Crossed the Atlantic and Central America Before Pacific Formation
Tropical Storm Greg originated from a tropical wave that moved off the west coast of Africa on 25 July 2023. The disturbance traveled westward across the tropical Atlantic before reaching the Caribbean region and crossing Central America on 3 August. After entering the eastern Pacific basin, the system gradually developed a more organized circulation and later became the eighth named tropical cyclone of the 2023 eastern Pacific hurricane season, designated EP082023.
The National Hurricane Center (NHC), responsible for monitoring tropical cyclones in the eastern Pacific and Atlantic basins, began tracking the disturbance as it moved over warm ocean waters. Satellite observations, including infrared and microwave imagery, documented increasing convection and the development of a closed circulation. At 0000 UTC on 14 August, the system strengthened into a tropical depression near 11.3°N, 138.2°W with maximum sustained winds of 30 kt and an estimated central pressure of 1007 mb.
Greg intensified into a tropical storm by 0900 UTC on 14 August near 11.3°N, 139.8°W. The cyclone continued westward across the eastern Pacific, remaining well south of Mexico and far from Central American coastlines. No coastal watches or warnings were issued because the storm did not threaten populated land areas.
After entering the central Pacific basin, responsibility for official forecasts shifted to the Central Pacific Hurricane Center (CPHC), which monitors tropical cyclones affecting the central Pacific region, including Hawaii. Greg's track remained over open ocean south of the Hawaiian Islands, preventing direct effects on island communities, maritime infrastructure, or coastal regions.
55-Knot Peak: Greg's Brief but Definitive Tropical Storm Phase
Greg reached its strongest intensity during 15–16 August 2023 while moving westward across the central Pacific. The NHC and CPHC final analysis determined that the cyclone maintained peak winds of 55 kt (63 mph) from 1800 UTC on 15 August through 1200 UTC on 16 August. The estimated minimum central pressure during its strongest period was 994 mb.
At 1200 UTC on 15 August, Greg was positioned near 11.1°N, 145.2°W with maximum sustained winds of 45 kt and an estimated central pressure of 1000 mb. The cyclone strengthened further later that day, reaching its official peak intensity while remaining over open waters. No reports of tropical-storm-force winds from ships were received during the storm's lifetime.
Satellite analysis showed Greg maintaining a compact tropical structure as it moved westward. Geostationary satellite imagery, microwave observations, scatterometer data, and objective satellite intensity estimates provided the basis for operational analysis because aircraft reconnaissance was not conducted over the storm.
The cyclone's forecast performance was documented after the season concluded. Official NHC track forecasts issued before Greg entered the central Pacific produced errors at or below the average values from the previous five-year period, while official intensity forecasts also performed better than the corresponding five-year averages during the limited forecast period.
Greg never approached the U.S. mainland, the Gulf of Mexico, Caribbean islands, or the Mexican coastline. Its strongest winds remained confined to remote maritime areas of the eastern and central Pacific.
Weakening Shear and Dissipation: Greg's Final Hours Over the Open Pacific
After reaching peak strength, Greg gradually weakened as environmental conditions became less favorable for maintaining organized deep convection. By 1500 UTC on 16 August, maximum sustained winds had begun to decrease, and the storm's structure became less organized.
Greg continued moving westward across the central Pacific on 17 August. At 0000 UTC, the storm was located near 12.0°N, 152.9°W with maximum sustained winds of 40 kt and an estimated central pressure of 1004 mb. Continued weakening followed as convection diminished and the circulation became increasingly exposed.
The system weakened to a tropical depression at 1800 UTC on 17 August near 12.2°N, 156.4°W. During the following day, only limited thunderstorm activity remained near the center as the depression continued westward across open waters.
Greg dissipated on 18 August 2023 near 11.0°N, 162.0°W. Its final analyzed position marked the end of a five-day tropical cyclone lifecycle that began with an African tropical wave and concluded over the open Pacific Ocean.
No Damage, No Casualties: Greg's Harmless Pacific Track by the Numbers
Tropical Storm Greg produced no reported fatalities, property damage, evacuations, or rescue operations. The cyclone remained far from populated areas throughout its lifetime, leaving the Americas, the U.S. Gulf Coast, the Caribbean region, Mexico, and Hawaii free from direct impacts.
The storm's principal meteorological significance lay in the evolution of its precursor disturbance. The tropical wave originated near Africa, crossed the Atlantic Ocean and Central America, developed into a tropical cyclone in the eastern Pacific, and later crossed into the central Pacific basin under the operational responsibility of the NHC and CPHC.
Greg's final best-track record lists formation at 0000 UTC on 14 August 2023 near 11.3°N, 138.2°W, intensification to tropical storm status at 0900 UTC the same day, peak intensity of 55 kt (63 mph) with an estimated minimum central pressure of 994 mb from 1800 UTC on 15 August to 1200 UTC on 16 August, weakening to a tropical depression at 1800 UTC on 17 August, and dissipation at 1800 UTC on 18 August 2023 near 11.0°N, 162.0°W.