Trackers:
USA Wildfire Tracker
Atlantic Hurricane Tracker

Sample Forecast for New Zealand

Summary for New Zealand

Synopsis: El Niño is expected to remain strong through the Southern Hemisphere summer 2015-16, with a transition to ENSO-neutral anticipated during late autumn or early winter 2016.

A strong El Niño continued during November as indicated by well above-average sea surface temperatures (SSTs) across the central and eastern equatorial Pacific Ocean. The Niño-4, Niño-3.4 and Niño-3 indices rose to their highest levels so far during this event, while the Niño-1+2 index remained approximately steady. The subsurface temperatures in the central and eastern Pacific, while still well above average, decreased slightly due to the eastward push of the upwelling phase of an equatorial oceanic Kelvin wave. Low-level westerly wind anomalies and upper-level easterly wind anomalies continued over the most of the tropical Pacific. The traditional and equatorial Southern Oscillation Index (SOI) values remained negative. These conditions are associated with enhanced convection over the central tropical Pacific and suppressed convection over Indonesia. Collectively, these atmospheric and oceanic anomalies reflect a strong El Niño episode that has matured.

Most models indicate that a strong El Niño will continue through the Southern Hemisphere summer 2015-16, followed by weakening and a transition to ENSO-neutral during the late autumn or early winter. The forecaster consensus remains nearly unchanged from last month, with the expectation that this El Niño will rank among the three strongest episodes as measured by the 3-month SST departures in the Niño 3.4 region dating back to 1950. El Niño is expected to remain strong through Southern Hemisphere summer 2015-16, with a transition to ENSO-neutral anticipated during the late autumn or early winter 2016.

North Island

Temperature

January

Almost all of the North Island should be near normal.

February

Almost all of the North Island should be slightly above normal except East Cape that should be near normal.

March

Almost all of the North Island should be slightly above normal except Southern Hawkes Bay that should be near normal.

April

Almost all of the North Island should be slightly to moderately above normal with the Hawkes Bay being closer to normal.

May

Almost all of the North Island should be slightly to moderately above normal with the Hawkes Bay being closer to normal.

June

Almost all of the North Island should be slightly above normal with Northland and East Cape being closer to normal.

Precipitation

January

From the west coast of Northland through the Waikato to Wellington and across to Taranaki should be near normal to slightly wetter in the southern part of the island. Only the east coast from Northland through to Hawkes Bay should be slightly drier than normal with some isolate areas perhaps moderately drier than normal.

February

Near normal to slightly wetter than normal across nearly the entire island with slightly wetter parts in far Northland and East Cape through Hawkes Bay and eastern Wellington. Slightly drier in the volcanic plateau.

March

Near normal to slightly drier than normal across most of the island with Gisborne and Hawkes Bay slightly to moderately drier than normal.

April

Northland down to the north Waikato should be near normal and the southern Waikato and northern Manawatu should be slightly wetter than normal with the Bay of Plenty and rest of Manawatu and Taranaki and Wellington near normal and the east coast from Gisborne south slightly to moderately drier than normal.

May

Near normal across the entire island.

June

Slightly to moderately wetter than normal across the eastern part of the island with the rest of the island near normal.

South Island

Temperature

January

Almost all of the South Island should be near normal.

February

Almost all of the South Island should be slightly to moderately above normal.

March

Almost all of the South Island should be slightly to moderately above normal.

April

Almost all of the South Island should be slightly to moderately above normal.

May

Almost all of the South Island should be slightly to moderately above normal.

@6 June Almost all of the South Island should be near normal to slightly above normal.

Precipitation

December

Most of the island should be slightly to moderately drier than normal except for the Canterbury Plains and North Canterbury that should be near normal.

January

Most of the western third of the island should be near slightly wetter than normal and the rest of the island near normal for the month.

February

Slightly drier than normal on the West Coast and the remainder of the island near normal.

March

Mix with most areas near normal but a chance of slightly wetter than normal conditions in the east and slightly drier in the interior of the northern third of the island.

April

Near normal to slightly wetter than normal across the island. Only a small area of Canterbury Plains potentially drier than normal.

May

Near normal in the west and slightly drier than normal in the east.

June

Normal in the west and slightly wetter than normal in South Canterbury.