Cyclone John

Category 5 Australian region cyclone in 1999

Severe Tropical Cyclone John
John near its peak intensity on 14 December
Meteorological history
Formed9 December 1999
Dissipated16 December 1999
Category 5 severe tropical cyclone
10-minute sustained (Aus)
Highest winds205 km/h (125 mph)
Lowest pressure915 hPa (mbar); 27.02 inHg
Category 4-equivalent tropical cyclone
1-minute sustained (SSHWS/JTWC)
Highest winds240 km/h (150 mph)
Overall effects
FatalitiesNone
DamageUnknown
Areas affectedWestern Australia
IBTrACSEdit this at Wikidata

Part of the 1999–00 Australian region cyclone season

Severe Tropical Cyclone John was an intense tropical cyclone that rapidly deepened offshore before devastating areas of Western Australia. The system was the second cyclone and first severe tropical cyclone of the active 1999–00 Australian region cyclone season. Cyclone John developed from a monsoon trough positioned northwest of Australia on 9 December 1999. As it moved to the west and later south as the result of a subtropical ridge under favourable conditions, the cyclone was able to rapidly intensify. John reached peak intensity on 14 December as a Category 5 cyclone on the Australian cyclone scale, the highest rating possible. Cyclone John later began interacting with a mid–latitude trough, which slightly weakened the cyclone prior to making landfall near Whim Creek early on 15 December. Increasingly unfavourable conditions further inland resulted in the cyclone's rapid weakening, before it dissipated during the next day.

Cyclone John extensively affected areas of Western Australia, but damage was not as bad as expected. Widespread power outages across the Pilbara region were caused by John. Strong winds caused minor damage to infrastructure across the coast, as well as tree damage. 140 windmills were destroyed by the cyclone on the coast. Further inland, rainfall associated with the cyclone and its remnants brought flooding, which flooded 25 houses and caused rivers to overflow. The system was responsible for no deaths and a limited amount of damage. After the season, the name John was retired from the Australian tropical cyclone naming list.

Meteorological history

A map of a path across the eastern Indian Ocean near Australia. Most of the country can be seen in the right side of the image. Some of the Indonesian islands are visible at the top.
Map plotting the storm's track and intensity, according to the Saffir–Simpson scale
  Tropical depression (≤38 mph, ≤62 km/h)
  Tropical storm (39–73 mph, 63–118 km/h)
  Category 1 (74–95 mph, 119–153 km/h)
  Category 2 (96–110 mph, 154–177 km/h)
  Category 3 (111–129 mph, 178–208 km/h)
  Category 4 (130–156 mph, 209–251 km/h)
  Category 5 (≥157 mph, ≥252 km/h)
  Unknown
Storm type
circle Tropical cyclone
square Subtropical cyclone
triangle Extratropical cyclone, remnant low, tropical disturbance, or monsoon depression