Seasonal Climate Outlook

Strong El Niño conditions continued to dominate the tropical Pacific during December 2015.

Strong El Niño conditions continue in the Tropical Pacific.

Atmospheric and oceanic anomalies in the equatorial Pacific reflect strong El Niño conditions.

Strong El Niño conditions were established across the Equatorial Pacific during September 2015.

Strong El Niño conditions are present in the tropical Pacific ocean.

El Niño conditions continued to strengthen during July 2015.

An El Niño event is under way in the tropical Pacific. Sea surface temperatures have continued to warm across many areas of the eastern and central Tropical Pacific.

An El Niño event is now under way in the tropical Pacific.

Warming of the sea surface across the equatorial Pacific Ocean continued in April 2015, building upon the warmer than normal waters observed in previous months.

Sea surface temperature anomalies in the tropical Pacific intensified significantly around the international Dateline during March 2015 and are currently showing a pattern consistent with weak El Niño conditions.

Sea surface temperatures across the equatorial Pacific Ocean continued to reflect conditions between neutral and weak El Niño states during February 2015. Atmospheric patterns were mostly indicative of weak El Niño-like conditions.

Sea surface temperatures across the equatorial Pacific Ocean are borderline between neutral and weak El Niño conditions.

Sea surface temperatures across the equatorial Pacific Ocean remained steady during December 2014 at above conventional El Niño thresholds.

In November 2014, the equatorial Pacific Ocean warmed significantly, reaching El Niño levels towards the end of the month.

At the end of October 2014, atmospheric and oceanic indicators in the tropical Pacific Ocean were at borderline El Niño thresholds.

During September 2014, borderline El Niño conditions returned in the Pacific.

The equatorial Pacific Ocean remains ENSO-neutral at the end of August 2014.

The equatorial Pacific Ocean continues to remain ENSO-neutral at the end of July 2014, with atmospheric and oceanic conditions failing to sufficiently couple to initiate an El Niño event

While above normal sea surface temperatures across the Tropical Pacific Ocean have crossed El Niño thresholds in June 2014, most atmospheric indicators (e.g. sea level pressure, convection, trade winds) have remained at neutral levels, indicating that El Niño conditions have not yet become fully established.

During June–August 2014, mean sea level pressures are expected to be lower than normal to the northeast of New Zealand, and weak lower than normal pressures are expected over the country.

May–July temperatures are most likely (50% chance) to be average for the west of the South Island, above average (50% chance) for the east of the North Island, and average or above average (40-45%) for all remaining regions of New Zealand. Cold snaps and frosts can still be expected in some parts of the country as autumn advances into winter.

The equatorial Pacific Ocean continued in a neutral state (neither El Niño nor La Niña) in March 2014. International guidance indicates that ENSO-neutral conditions are the most likely outcome for the next three months (April – June 2014).

During March–May 2014, mean sea level pressures are expected to be lower than normal to the north of the country, with higher pressures than normal to the southeast of New Zealand.

The equatorial Pacific Ocean continued in a neutral state (neither El Niño nor La Niña) in January 2013.