New Zealand Flooding 2017

Start Date

April 6, 2017


Flooded town in New Zealand.

Credit: Higgins Storm Chasing

The NASA Disasters Program is assisting New Zealand authorities to respond to flooding resulting from Tropical Cyclones Debbie and Cook. On April 6, 2017, New Zealand declared a state of local emergency for the Whakatane region as a result of rains from Debbie. The region was expanded on April 11, 2017 to include the greater East Bay of Plenty region as impending rains from Cook will further stress local water systems. To date, 2,000 people have been evacuated.

NASA Disasters will furnish stream flow and inundation predictions and flood maps generated from synthetic aperture radar data from ESA’s Sentinel-1 mission.

Latest Updates

April 17, 2017
SAR flood extent map for Aukland New Zealand.
Following a Sentinel-1 acquisition over eastern North Island, covering Auckland on April 14, 2017 at 17:37h UTC, a synthetic aperture radar (SAR) flood proxy map (FPM)  was developed as a KMZ overlay (available for download here) This FPM covers an area of 175-by-500 km, derived from Sentinel-1's pre- (2016-04-02) and post-event (2017-04-14) SAR amplitude images. The colored pixels...
April 14, 2017
IMERG precipitation accumulation from New Zealand.
Two extra-tropical cyclones recently dropped very heavy rain over New Zealand, Debbie and Cook. As Cook's remnants continue to move away, NASA analyzed the heavy rainfall generated from the double extra-tropical punch. Tropical cyclone Debbie dumped extreme amounts of rain over the northeastern coast of Australia when it hit the Queensland coast on March 28, 2017. After drenching northeastern Australia Extra-tropical Cyclone Debbie transported a river of water over New...
April 13, 2017
SAR flood maps of 2017 New Zealand floods.
Below are images of a SAR Flood Map derived from ESA Sentinel-1 data for April 4, 2017. Flood regions were detected by measuring the difference in radar images acquired on April 4 and March 11 by Sentinel-1. Newer products will be developed when the data becomes available from ESA. On the KML file, red areas indicate flood presence. The point of contact for this data is: Layers, top to bottom: Light Blue is reference water extent mapped via NASA 90 m (spatial resolution) SWBD. Red is flood water...
April 12, 2017
Sentinel-1 Comparison of 2017 New Zealand floods.
Change detection map of recent flooding in New Zealand 3/11/17 vs. 4/11/17 using Sentinel-1 data. Red areas indicate flooding.  Please ignore the change detection that is observed over the open ocean - the product does not incorporate a water mask at this time. 
April 11, 2017
2017 New Zealand flood forecast from the GFMS.
The GFMS uses real-time TRMM Multi-satellite Precipitation Analysis (TMPA) precipitation information as input to a quasi-global hydrological runoff and routing model.  In addition, the latest maps of instantaneous precipitation and totals from the last day, three days and seven days are displayed. Flood detection/intensity estimates are based on 13 years of retrospective model runs with TMPA input, with flood thresholds derived for each grid location using surface water storage statistics.  Streamflow, surface water storage, and inundation variables are also calculated at 1km...