Rainfall Summaries

Toggle between tabs to see different results breakdowns.

Annual totals

Current year

Annual total rainfall (mm) at a range of monitoring sites across the region. The shaded areas under the monitoring sites show the long term mean annual rainfall over the entire region.

Usage guide: Drag, scroll, and use the top right +/- buttons on the map to move and zoom to areas of interest. Hover over site circles to see more information and use the selection box on the top left ( ) to subset the table data below to sites in that area.

Sites with greater than 20 percent difference from their long-term average have table rows shaded orange (below average) or blue (above average). Click on rows to highlight those sites on the map above and click on table headers or the arrows next to them (
) to sort the data by that column.

Long-term

Annual totals rainfall (mm) at a number of sites are shown against the site average total (black line). Years when recorded rainfall was above average are coloured orange while years with below average rainfall are blue. Hover over charts to see specific values and click on legend entries to show/hide that series.

Kāpiti Coast

Te Awarua-o-Porirua

Te Whanganui-a-Tara

Ruamāhanga

Wairarapa Coast

Subannual totals

Monthly totals

Monthly rainfall totals at a number of rainfall monitoring sites compared to the previous year and the long-term monthly average/range. Hover over charts to see specific values and click on legend entries to show/hide that series.

Kāpiti Coast

Te Awarua-o-Porirua

Te Whanganui-a-Tara

Ruamāhanga

Wairarapa Coast

Cumulative monthly totals

The cumulative monthly rainfall for 2019/20 at a number of rainfall monitoring sites is compared to the previous year and the long-term average. Hover over charts to see specific values and click on legend entries to show/hide that series.

Kāpiti Coast

Te Awarua-o-Porirua

Te Whanganui-a-Tara

Ruamāhanga

Wairarapa Coast

Seasonal totals

Seasonal rainfall totals for monitoring sites are presented below. Those sites that have a greater than 20 percent difference from their long-term seasonal average are shaded orange (below average) or blue (above average). Click on table headers or the arrows next to them (
) to sort the data by that column.

Maximum recorded rainfalls

The highest and lowest recorded rainfall totals throughout the year at various monitoring sites have been assigned estimated return periods based on frequency analysis of long term recorded data (see NIWA’s HIRDS V4 for more information). Blue shaded values indicate a rainfall total with a 5-year return period or greater. Toggle between 'Short duration' and 'Long duration' to see different length summary periods and click on table headers or the arrows next to them (
) to sort the data by that column.

Note that for all frequency analysis results (rainfall and flows) a return period expressed as 100 years can be assigned a probability of occurring being 1/100, or 1% in any one year. Similarly, a 5-year return period event equates to 1/5 or a 20% chance of occurring in any one year.

Short duration
Long duration

Lowest recorded rainfalls

Minimum total rainfalls over periods of 14, 28, and 90 days. Click on table headers or the arrows next to them (
) to sort the data by that column.