08th November 2018 TONGAN El Niño–Southern Oscillation (ENSO ) status.
The tropical Pacific Ocean made a significant transition towards El Niño conditions during October 2018. Sea surface temperatures in the equatorial Pacific warmed during October and the SOI was slightly positive (=0.2).
Recent
October 2018:
Again extremely high rainfall received in Niuafo’ou which recorded its 4th highest October rainfall. Above average rainfall recorded in Niuatoputapu, Vava’u and Ha’apai. Below average rainfall in Tongatapu. (Refer to Graph below). The average temperature was 25.5°C which was 1.0°C warmer than average. Highest maximum temperature was 32.9oC on the 25th in Niuafo’ou and the lowest minimum temperature was 17.0oC in Fua’amotu on the 20th.
Forecast
There is approximately more than 80% chance for El Niño conditions establishing during November 2018- January 2018
Note:
Tropical cyclone season also known as the wet season officially started on the 1st of November until the end of the following April.
However, with the El Niño like conditions evolving in the Pacific ocean and may affect Tonga’s rainfall pattern during the coming months, we may see some effects of water shortage throughout the country during this time especially Tongatapu and Ha’apai which is now experi-encing El Niño like conditions.
Given the current seasonal forecast in Table 1, the ENSO status above and the rainfall observation for the last 3 months especially about Tongatapu, it is advisa-ble to use water wisely and collect as much water as possible when it rains. It is encouraged that public be aware and use water wisely and seek advice from rele-vant authorities of sensitive sectors, e.g. Agriculture, Water, Health and the National Emergency Manage-ment Office (NEMO) on the best practices to minimize the effects of natural disasters. It is important to know the impact of El Niño and receiving less rainfall than usual which affects our islands.
The next Climate update will be issued early December 2018
ENDS
Issued by the Tonga Meteorological Service (MEIDECC)