Misplaced Pages

1969–70 South Pacific cyclone season
Season summary map
Seasonal boundaries
First system formed	February 10, 1970
Last system dissipated	April 19, 1970
Strongest storm
Name	Dolly & Emma
• Maximum winds	130 km/h (80 mph) (10-minute sustained)
• Lowest pressure	965 hPa (mbar)
Seasonal statistics
Total disturbances	7
Tropical cyclones	5
Severe tropical cyclones	2
Total fatalities	6
Total damage	$5 million (1970 USD)
Related articles
1969–70 South-West Indian Ocean cyclone season 1969–70 Australian region cyclone season
South Pacific tropical cyclone seasons 1950s, 1960s, 1969–70, 1970–71, 1971–72

The 1969–70 South Pacific cyclone season was a very inactive season, featuring only seven disturbances, five tropical cyclones, and two severe tropical cyclones. The season featured only one landfalling storm, Cyclone Dawn. Dawn formed very late, on February 10, and the last storm, Tropical Depression Isa, dissipated early, on April 19. On January 2, a tropical low developed onto a weak depression on the Coral Sea. It later crossed into the Australian Region, where it strengthened onto Severe Tropical Cyclone Ada.

Seasonal summary

Systems

Tropical Cyclone Dawn

Category 2 tropical cyclone (Australian scale)
Duration	February 16 – February 19
Peak intensity	100 km/h (65 mph) (10-min); 980 hPa (mbar)

Dawn formed on February 16 on the Gulf of Carpentaria as a tropical low. It strengthened to a Category 2 tropical cyclone (Australian scale) before dissipating, northwest of Brisbane on the South Pacific basin.

Severe Tropical Cyclone Dolly

Category 3 severe tropical cyclone (Australian scale)
Category 1 tropical cyclone (SSHWS)
Duration	February 11 – February 25
Peak intensity	130 km/h (80 mph) (10-min); 965 hPa (mbar)

Dolly formed to the east of Luganville on February 11, and was last noted on February 25 to the north of French Polynesia. It peaked as a Category 1 tropical cyclone (SSHWS) or Category 3 severe tropical cyclone (Australian scale).

Severe Tropical Cyclone Emma

Category 3 severe tropical cyclone (Australian scale)
Category 1 tropical cyclone (SSHWS)
Duration	February 27 – March 6
Peak intensity	130 km/h (80 mph) (10-min); 965 hPa (mbar)

Severe Tropical Cyclone Emma originated as a depression to the west of Wallis and Futuna. It moved to the south-southeast before it was last noted on March 6 to the north of French Polynesia.

Tropical Cyclone Gillian

Category 1 tropical cyclone (Australian scale)
Tropical storm (SSHWS)
Duration	April 7 – April 11
Peak intensity	85 km/h (55 mph) (10-min); 980 hPa (mbar)

A disturbance developed to a depression, to the south-southwest of Fiji. It continued its L movement while strengthening to a tropical cyclone before weakening due to the cold waters and wind shear. Gillian was last noted, far south of Marshall Islands as it dissipated. It was strengthened to a equivalent of a tropical storm on the SSHWS scale.

Tropical Cyclone Helen

Category 1 tropical cyclone (Australian scale)
Tropical storm (SSHWS)
Duration	April 13 – April 17
Peak intensity	75 km/h (45 mph) (10-min); 990 hPa (mbar)

A tropical low developed to a depression, south of Tuvalu. It traveled to the west, strengthening as Tropical Cyclone Helen before weakening. It was last noted on April 17, south-southwest of Fiji.

On April 17, 1970, Apollo 13 was making its final descent over the splashdown zone when they spotted a weakening Helen as they were re-entering the Earth's atmosphere. Mission control had been tracking the storm to make sure it did not interfere with the mission's re-entry.

Tropical Cyclone Isa

Category 1 tropical cyclone (Australian scale)
Tropical depression (SSHWS)
Duration	April 14 (entered basin) – April 19
Peak intensity	75 km/h (45 mph) (10-min); 990 hPa (mbar)

It was unknown if the precursor to Isa was noted to the southeast, or to the southwest of Solomon Islands. It strengthened to a Category 1 tropical cyclone (Australian scale), but it remained a tropical depression (SSHWS). It was last noted on April 19, as it dissipated.

Other systems

During January 5, the Australian Bureau of Meteorology first noted the existence of a weak tropical depression over the eastern Coral Sea, however, it has since been determined that the depression developed during January 2 near 15°48′S 165°06′E / 15.8°S 165.1°E / -15.8; 165.1. The system was subsequently tracked by infrequent satelitte imagery, which revealed that it slowly completed a cyclonic loop near the Solomon Islands before curving back toward the southwest. The system entered the Australian region during 15 January, where it subsequently became Severe Tropical Cyclone Ada before making landfall on Queensland during 17 January.

Seasonal effects

References

1. ^ Gibbs, W. J. (June 1970). "Report by Director of Meteorology on Cyclone 'Ada'" (PDF). Bureau of Meteorology. Retrieved 22 April 2017.
2. "Australian Tropical Cyclone Database" (CSV). Australian Bureau of Meteorology. 2023-06-30. Retrieved 2023-06-30. A guide on how to read the database is available here.
3. Smith, Ray (1990). "What's in a Name?" (PDF). Weather and Climate. 10 (1). The Meteorological Society of New Zealand: 25. doi:10.2307/44279572. JSTOR 44279572. S2CID 201717866. Archived from the original (PDF) on November 29, 2014. Retrieved March 28, 2014.
4. "1970 Tropical Cyclone Emma (1970058S15200)". International Best Track Archive for Climate Stewardship. Retrieved October 21, 2019.

External links

• Atlantic hurricane seasons: 1969, 1970
• Eastern Pacific hurricane seasons: 1969, 1970
• Western Pacific typhoon seasons: 1969, 1970
• North Indian Ocean cyclone seasons: 1969, 1970
• World Meteorological Organization
• Australian Bureau of Meteorology
• Fiji Meteorological Service
• New Zealand MetService
• Joint Typhoon Warning Center

• 1969–70 South Pacific cyclone season
• South Pacific cyclone seasons