1969–70 South Pacific cyclone season

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1969–70 South Pacific cyclone season
1969-1970 South Pacific cyclone season summary.jpg
Season summary map
Seasonal boundaries
First system formedFebruary 10, 1970
Last system dissipatedApril 19, 1970
Strongest storm
NameDolly & Emma
 • Maximum winds130 km/h (80 mph)
(10-minute sustained)
 • Lowest pressure965 hPa (mbar)
Seasonal statistics
Total disturbances7
Tropical cyclones5
Severe tropical cyclones2
Total fatalities6
Total damage$5 million (1970 USD)
Related articles
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.

Seasonal summary[]

Tropical cyclone scales#Comparisons across basins

On January 2, a tropical low developed onto a weak depression on the Coral Sea. It completed a cyclonic loop before entering the Australian Region, as it strengthened onto Severe Tropical Cyclone Ada. The last disturbance for this season was Tropical Cyclone Isa, which existed from April 14 – April 19.

Systems[]

Tropical Cyclone Dawn[]

Category 2 tropical cyclone (Australian scale)
Tropical storm (SSHWS)
Dawn 1970 track.png 
DurationFebruary 16 – February 19
Peak intensity100 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 as a tropical storm (SSHWS) , or 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)
Dolly 1970 track.png 
DurationFebruary 11 – February 25
Peak intensity130 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)
Emma 1970 track.png 
DurationFebruary 27 – March 6
Peak intensity130 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)
Gillian 1970 track.png 
DurationApril 7 – April 11
Peak intensity85 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)
Helen 1970 track.png 
DurationApril 13 – April 17
Peak intensity75 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)
Isa 1970 track.png 
DurationApril 14 – April 19
Peak intensity75 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

 WikiMiniAtlas
15°48′S 165°06′E / 15.8°S 165.1°E / -15.8; 165.1.[1][2] 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.[1] 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.[1]

Seasonal effects[]

Name Dates active Peak classification Sustained
wind speeds
Pressure Areas affected Damage
(USD)
Deaths Refs
Priscilla December 15 – 19 Category 1 tropical cyclone 75 km/h (45 mph) 990 hPa (29.23 inHg) Fiji Minor [3]
Ada January 2 – 15 Tropical depression 55 km/h (35 mph) 997 hPa (29.44 inHg) Vanuatu, Solomon Islands None None
Dawn February 10 – 19 Category 1 tropical cyclone 65 km/h (40 mph) 990 hPa (29.23 inHg) New Caledonia and Northern Queensland $5 Million 6
Dolly February 11 – 25, 1970 Category 3 Severe Tropical Cyclone 130 km/h (80 mph) 965 hPa (28.50 inHg) [4]
Emma March 2 – 4, 1970 Category 3 Severe Tropical Cyclone 130 km/h (80 mph) 965 hPa (28.50 inHg) [5]
Season aggregates
7 systems October 29 – March 23

References[]

  1. ^ a b c Gibbs, W. J. (June 1970). "Report by Director of Meteorology on Cyclone 'Ada'" (PDF). Bureau of Meteorology. Retrieved 22 April 2017.
  2. ^ "The Australian Tropical Cyclone Database" (CSV). Australian Bureau of Meteorology. A guide on how to read the database is available here.
  3. ^ Waygood, J.L.M. (October 20, 1980). Tropical Cyclones affecting Fiji: November 1969 to April 1980 (Information Sheet No. 59). Fiji Meteorological Service.
  4. ^ "1970 Tropical Cyclone Dolly (1970043S15163)". International Best Track Archive for Climate Stewardship. Retrieved October 21, 2019.
  5. ^ "1970 Tropical Cyclone Emma (1970058S15200)". International Best Track Archive for Climate Stewardship. Retrieved October 21, 2019.

External links[]

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