A brief summary of climate and hydrological conditions in the region.
This service is regularly updated during periods in which closer monitoring is required (regardless of time of the year), in recognition that there is potential for dry spells, or irregular hydrological recharging. It does not define an official council position on drought or drought declaration. Outside of dry periods, less frequent updates synchronise with our latest seasonal outlooks.
Updated 13 August 2026
Next update due when there is a significant change of conditions or a new seasonal outlook.
Background
Autumn and early winter 2026 were characterised by a residual easterly flow, still resembling an earlier La Niña pattern with above average rainfall in the east. Large floods in the Wairarapa have caused significant localised damage in some areas, particularly south of Martinborough. We have also had occasional atmospheric river events and a number of flash flooding thunderstorms around the region, with relatively warm and very moist air masses affecting both Wellington and the Hutt. Localised thunderstorms can be very damaging and are virtually impossible to accurately predict in a timely fashion. From late winter onwards, the atmosphere started displaying a more wintery south-westerly flow, with progressively drier conditions east of the main ranges.
Current situation
Soil moisture levels were sitting at the normal or above average mark around mid-August, with a south-westerly flow more typical of El Niño years starting to take shape. While the past month has seen much less rainfall than earlier in winter, river flows and groundwater levels are generally holding up and tracking well within the historical normal range for this time of year. Some catchments in the Wairarapa (e.g. the Tauānui and Tūranganui) are still feeling the effects of the autumn and early winter floods with significant channel reconfiguration and bank erosion.
Meteorological outlook
The current El Niño event is predicted to be one of the strongest in recorded history with severe global impacts, albeit possibly of short duration. Impacts in the Wellington Region can be variable and ‘hit and miss’, as we are in a transition zone, and essentially every El Niño is different with its own “signature”. Compared to other parts of the world, the typical El Niño impacts in our region are therefore only mild. On average, there is an increased likelihood of strong westerly winds with increased heat and dryness in the Wairarapa between spring and autumn, and cooler weather with average or above average rainfall west of the main ranges. Note that during traditional El Niños the water temperatures around New Zealand tend to be cooler than average, i.e., forming a pattern which can contribute to creating a drying signature on the eastern coast. This is predicted to happen towards the end of the year and will likely be felt more during early summer. During the historical summer El Niños of 1982/83 and 1997/98 depicted below, it was wetter than normal over the Tararua ranges and Kāpiti coast, and drier than normal in the Wairarapa and southern parts of the region, including Wellington city.
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| Rainfall anomalies during summer for the historical previous strongest El Niños on record of 1982/83 and 1997/98. We can see that both cases had rainfall above average over the Tararua ranges and around Kāpiti, with below average rainfall in the Wairarapa, south of Wellington city and Baring Head. | |
The table below summarises potential El Niño impacts for the Wellington region as a whole, during the coming spring and summer months. In light of the potential for extended dryness over the summer months in the Wairarapa, we strongly recommend a continuous monitoring of how the hydrological conditions will evolve during spring, along with the seasonal outlooks and daily data available on our seasonal climate portal and also by Earth Sciences New Zealand.
| Projected El Niño climate impacts for spring and summer – global and region wide summary | Spring 2026 | Summer 2026-2027 |
|---|---|---|
| High confidence global projections | There is high confidence that this El Niño will be one of the strongest in recorded history, with severe global impacts. However, the Wellington Region is located in a transition area, and El Niño impacts are normally only mild for us compared to other areas of the world such as South America, California, Australia and South-east Asia | The event, albeit very strong, might be short lived and start decreasing in intensity towards the second half of summer |
| Overall projected regional Impacts | Increased westerly winds and gusts, moderate to severe drying in the Wairarapa (especially eastern coast) and Baring Head area. Likely low flows east of the main ranges, and increased fire risk in several areas including Baring Head and Wairarapa | As per spring, with drying effects reaching their peak and likely starting to decrease into autumn |
| Areas of uncertainty | Every El Niño is unique and not every event will have a clear dry pattern in spring | Every El Niño is unique and not every event will have a clear dry pattern in summer |
Climate change
The ‘normal’ longer-term water balance is becoming increasingly hard to maintain quite possibly due to climate change influences, and increased high frequency climate variability, with more unreliable weather patterns. Droughts are expected to become more severe and frequent in the Wellington region, particularly in the Wairarapa. Even if international climate policy efforts were to successfully contain global warming under 1.5-2 degrees (the Paris Agreement’s ambition), it is important that we enhance our water resilience and be prepared for more unreliable climate patterns with both extreme dry and extreme wet periods. We note that the warming of the land also means that evapotranspiration will greatly increase, so the soil will likely need more ongoing rain to maintain ideal moisture levels, compared to what it has needed in the past.
View the latest national drought index state
View the national drought forecasting dashboard
View the latest seasonal report:
Climate drivers and seasonal outlook for the Wellington Region - Autumn 2026 summary Winter 2026 outlook
date_range Published 15 Jun 2026
Download now (PDF 2.1 MB) get_appBrowse the data
Anomaly Maps
How different has recent rainfall/soil moisture been compared with the same time in previous years?
Site-specific graphs
| Area | Rainfall | Soil Moisture |
| Kapiti Coast (lowland) | Otaki at Depot | |
| Kapiti Coast (high altitude) | Penn Creek at McIntosh | |
| Porirua | Horokiri Stream at Battle Hill | |
| Wellington City | Kaiwharawhara Stream at Karori Reservoir | |
| Hutt Valley (upper catchment) | Hutt River at Kaitoke Headworks | |
| Upper Hutt | Upper Hutt at Savage Park | Upper Hutt at Savage Park AQ |
| Wainuiomata | Wanuiomata River at Wainui Reservoir | |
| Wairarapa (high altitude) | Waingawa River at Angle Knob | |
| Wairarapa Valley (north) | Kopuaranga River at Mauriceville | |
| Wairarapa Valley (Masterton) | Ruamahanga River at Wairarapa College | Wairarapa College AQ |
| Wairarapa Valley (south) | Tauherenikau River at Racecourse | Tauherenikau River at Racecourse |
| Wairarapa (north-eastern hills) | Whareama River at Tanawa Hut | Whareama River at Tanawa Hut |
| Wairarapa (south-eastern hills) | Waikoukou at Longbush | Waikoukou at Longbush |
Get in touch
- Phone:
- 0800496734
- Email:
- info@gw.govt.nz