Drought warning remains in force for Tonga [1]
Thursday, February 19, 2015 - 17:22
With below average rainfall expected over the next three-months, drought warnings remain in force for the whole of the Tonga group.
However, the El Nino warning previously in force for Tonga has now been downgraded to an El Nino watch.
The Tonga Meteorological Services said El Nino events normally last for around a year, however they can be shorter or last much longer depending on the nature of the event. The effect on Tonga varies but usually it brings cooler dry seasons and drier wet seasons than normal and more cyclones.
Tonga can expect at least one cyclone a year increasing to two during El Nino years. Drier than normal conditions have been experienced throughout central Tonga (Vava’u and Ha’apai) and southern Tonga (Tongatapu and 'Eua) from July to December last year, and the tropical Pacific sea surface temperatures are likely to remain within the neutral range for at least the next three-months.
Drought
In the current situation, rainfall received across Tonga in January this year eased some of the dry conditions experienced over the last six-months, with normal to above rainfall recorded in Ha’apai and Vava’u, while the rest of Tonga was still below normal.
The weather office said that the late summer to early autumn period is the time of the year when El Nino events naturally decay and forecasting beyond this time is difficult and some caution should be exercised.
The outlook for the next three-months (March-May) is for rainfall to below average to average for Vava’u, Ha’apai and Tongatapu and above average for the Niuas. Because this is the rainy season, rainfall is expected to increase naturally but the rainfall outlook for the next three-months remains below average.
“If below average rainfall is experienced from January to March 2015, which is the peak season of the rainy season then rainfall deficits could become a problem by mid this year."
May to October is the dry season but with the current outlook, the public is advised to use water wisely and collect as much rainwater as possible during the rain. Drought warnings are now in force for the whole of Tonga group.
Tonga Met advises rainfall and tropical cyclone sensitive sectors such as Agriculture and Fisheries (Food Security), Health, Water Resource Management, Tourism, and Disaster management should continue drought response operations and promote the conservation of water.