NZ Historic Weather Events Catalogue

XML

May_2021_Canterbury_Flooding ( 2021-05-29 )

A deep low centred to the west of the North Island brought widespread rain to most of New Zealand. Heavy rainfall developed in many parts of Canterbury, resulting in severe flooding causing much disruption and damage.

New Zealand

Multi HazardMulti Hazard at New Zealand
Comments:

Insurance ClaimInsurance claims totalled $46.44 million.

CommentMetService SEVERE WEATHER at MetService at 9:15 pm Friday 28-May-2021. A significant heavy rainfall event for Canterbury. Heavy rain also for parts of central New Zealand, and severe gales for the South Island west coast. A complex low pressure system over the Tasman Sea is forecast to move slowly southeastwards across northern and central New Zealand over the weekend, before moving away to the east on Monday. This system is expected to direct a strong and moist southeast flow across the South Island during this time, delivering an extended period of significant heavy rainfall to Canterbury, and severe gale southeasterlies along the South Island west coast. In addition, an associated front is forecast to move eastwards across northern and central New Zealand on Saturday, delivering a relatively short burst of heavy rain to some areas. This is expected to be a significant heavy rainfall event for Canterbury. A Red Warning for Heavy Rain is in force for the region south of Amberley, and an Orange Warning for Heavy Rain is now in force for the region from Amberley to Kaikoura. Dangerous river conditions and flooding are expected. Slips and floodwaters are likely to disrupt travel, making some roads impassable and possibly isolating communities. The Strong Wind Watch for Fiordland and Westland south of Hokitika has also been upgraded to a Warning for severe southeasterly gales.

CommentMetService SEVERE WEATHER WARNING at 8:42 pm Saturday 29-May-2021. A severe heavy rainfall event for Canterbury. Heavy rain also for parts of central and southern New Zealand, and severe gales for parts of the South Island. A complex low pressure system over the Tasman Sea is forecast to move slowly southeastwards across northern and central New Zealand over the weekend, before moving away to the east on Monday. This system is expected to direct a strong and moist southeast flow across the South Island during this time, delivering an extended period of significant heavy rainfall to Canterbury, and severe gale southeasterlies along the South Island west coast south of Hokitika. Severe southeast gales are also possible in Canterbury, especially about the coast and the Banks Peninsula. Another front is forecast to move onto Otago from the east during Sunday, delivering a period of rain, possibly heavy, to Dunedin and North Otago where a Heavy Rain Watch is now in force. This is expected to be a severe heavy rainfall event for Canterbury.A Red Warning for Heavy Rain is in force for the region south of Amberley, and an Orange Warning for Heavy Rain is in force for the region from Amberley to Kaikoura. Dangerous river conditions and flooding are expected. Slips and floodwaters are likely to disrupt travel, making some roads impassable and possibly isolating communities.

CommentMetService SEVERE WEATHER WARNING SEVERE WEATHER WARNING at 8:23 pm Sunday 30-May-2021. A severe heavy rainfall event for Canterbury. Heavy rain also for parts of Marlborough, eastern Otago and Southland, and severe gales for parts of the South Island. A complex low pressure system over northern New Zealand is expected to continue bringing widespread heavy rainfall into the Canterbury region, which remains under a Red Warning. Heavy rain is also forecast for Marlborough about and south of Kaikoura where an Orange Warning remains in force. A period of heavy rain is also possible about eastern parts of Otago and Southland where Heavy Rain Watches are in place. This low pressure system is forecast to move away to the east of the country on Monday. In addition, severe gale southeasterlies are expected along the South Island west coast south of Hokitika, and also for the Canterbury coast north of Ashburton, including Banks Peninsula. The remainder of Canterbury remains under a Strong Wind Watch, while southern parts of Marlborough are also covered by a Strong Wind Watch. This is a severe heavy rainfall event for Canterbury. Dangerous river conditions and widespread flooding are ongoing. Slips and floodwaters are disrupting travel, making some roads impassable and isolating communities. Further power outages are also likely.

CommentMetService SEVERE WEATHER at 10:21 am Monday 31-May-2021. A severe heavy rainfall event for Canterbury. Heavy rain also for parts of Marlborough. Severe gales for parts of the South Island. A humid southeast flow is expected to bring further heavy rain to parts of Canterbury, which remain under a Red Warning, although rain is easing or expected to ease during the course of the day. A heavy rain Warning (orange)also remains in force for Marlborough about and south of Kaikoura. In addition, severe gale southeasterlies are expected along coastal areas of Canterbury about and north of Banks Peninsula this morning, while a Watch remains in force for coastal areas of Marlborough. This is a severe heavy rainfall event for Canterbury. Dangerous river conditions and widespread flooding are still ongoing in some areas. Slips and floodwaters are disrupting travel, making some roads impassable and isolating communities. Further power outages are also likely.

CommentMetService SEVERE WEATHER at 8:12 pm Monday 31-May-2021. Red Warning for mid-Canterbury now lifted, but an Orange Rain Warning remains in force for the far north of Canterbury and southern Marlborough. The rain has now eased to showers across much of the Canterbury region, and the Red Warning for Heavy Rain is now lifted. However, an Orange Warning for Heavy Rain remains in force for Canterbury about and north of Cheviot, and Marlborough about and south of Kaikoura until midnight tonight (Monday), with rain then easing to showers in this area. Any remaining showers through Canterbury and southern Marlborough should clear by early Tuesday afternoon, and no further rain is expected for the remainder of the week. Please be aware, following the Red Warning for Canterbury, rivers will remain swollen for some time. Floodwaters will also take time to recede, so please continue to follow advice from local authorities, civil defence and emergency services.

Canterbury

FloodingFlooding at Canterbury
Comments:

Declared EmergencyA region-wide State of Local Emergency was declared by the Civil Defence Emergency Management Group. This remained in place for Ashburton, Selwyn, and Waimakariri districts until 11 June, but was lifted elsewhere about 5 June.

CommentSome parts of the Canterbury floods were so extreme that they were only expected to happen once every 200 years. During the floods Mt Somers recorded its largest 48-hour rainfall ever, with 526 mm. Rainfall stations nearer to the coast (Ashely, Oxford, Darfield, and Methven) recorded 48-hour rainfall amounts that would be expected about once every 50 years.

CommentOn 1 June the event was declared a medium-scale adverse event for the Cantterbury region, which provided $500,000 in government funding for recovery measures for the region.

CommentThe flooding situation was most severe in the mid Canterbury, Ashburton and Hinds areas, particularly at Ashburton Forks and Thompson’s Track. Rivers in the upper parts of those catchments were flowing very high, with gauges recording some of the highest volumes ever measured.

Affected LifelineState Highway 73 from Springfield to Castle Hill was closed due to slips and flooding. State Highway 79 from Fairlie to Geraldine was also closed due to flooding.

EvacueesPeople were evacuated from Springfield, the Upper and Lower Selwyn Huts, and Peel Forest.

CommentFederated Farmers reported there had been multiple rescues of farmers and other members of the public, as well as stock losses. In addition, it was anticipated that winter feed would be in short supply over the coming months, as a lot of it had been washed away by the flooding.

Affected LifelineMany roads, including some sections of state highways were closed.

CommentMore than 70 schools, kura, and early learning services in Canterbury were closed.

CommentThe Ashburton District Council asked residents to boil their water used for drinking and food preparation.

FloodingFlooding at Ashburton
Map Location: -43.902384 171.736416
Comments:

Declared EmergencyA State of Emergency was declared in Ashburton. Ashburton activated its Civil Defence Emergency Operation Centre.

DamageThree bridges in the Ashburton district collapsed or were washed away.

The Ashburton Bridge on State Highway 1 was closed about 8am on 1 June after motorists reported they could feel it slumping underneath them. One section of the bridge had slumped by about 10cm. The bridge closure meant there was no alternate route to the south of Ashburton, as all other road options were closed. Typically 21,000 vehicles go over the bridge on a weekday, and 30,000 on a weekend day. The bridge reopened for light traffic late on 1 June, and for heavy vehicles on 3 June.

CommentAshburton recorded more than double its monthly average rainfall for May within a 24-hour period.

CommentAshburton College was closed on the advice of Civil Defence.

FloodingFlooding at Timaru
Map Location: -44.398445 171.255200
Comments:

Declared EmergencyA State of Emergency was declared in Timaru.

CommentThere were multiple road closures in the local area.

CommentCivil defence centres were opened in Timaru, Temuka, and Geraldine.

FloodingFlooding at Christchurch
Map Location: -43.531120 172.636147
Comments:

Affected LifelineSurface flooding in Christchurch knocked out power to several hundred homes, and closed a number of streets.

References

Insurance Council of New Zealand (https://www.icnz.org.nz/natural-disasters/cost-of-natural-disasters/)
Meteorological Society of New Zealand (Inc.), Newsletter 165, Winter 2021.
Meteorological Society of New Zealand (Inc.)
Headline: Canterbury flooding: Christchurch roads closed by waters.
www.radionz.co.nz, 30 May 2021.
Headline: Live Canterbury flooding updates: Thousands of homes at risk.
www.radionz.co.nz, 30 May 2021.
Headline: Canterbury flooding: Thousands in Ashburton prepare to evacuate.
www.radionz.co.nz, 31 May 2021.
Headline: Live Canterbury flooding updates: Bridges collapse, hundreds of homes evacuated.
www.radionz.co.nz, 31 May 2021.
Headline: Canterbury floods: Rain to ease in Southern Canterbury but heavy rain warning still in place.
www.stuff.co.nz, 31 May 2021.
Headline: Live Canterbury floods: Rain easing, river levels dropping.
www.radionz.co.nz, 1 June 2021.
Headline: Canterbury flooding: Ashburton Bridge on State Highway 1 closes.
www.radionz.co.nz, 1 June 2021.
Headline: Canterbury flooding: Adverse event declared in region.
www.radionz.co.nz, 1 June 2021.
Headline: Ashburton Bridge reopens for light traffic.
www.radionz.co.nz, 2 June 2021.
Headline: Ashburton Bridge to open to heavy vehicles today - NZTA.
www.radionz.co.nz, 3 June 2021.
Headline: Canterbury flooding: State of emergency to continue for a week.
www.radionz.co.nz, 4 June 2021.
Headline: Some of Canterbury’s floods labelled a one-in-200-year event.
www.stuff.co.nz, 14 June 2021.

May_2021_Canterbury_Flooding ( 2021-05-29 )

A deep low centred to the west of the North Island brought widespread rain to most of New Zealand. Heavy rainfall developed in many parts of Canterbury, resulting in severe flooding causing much disruption and damage.

New Zealand

Multi HazardMulti Hazard at New Zealand
Comments:

Insurance ClaimInsurance claims totalled $46.44 million.

CommentMetService SEVERE WEATHER at MetService at 9:15 pm Friday 28-May-2021. A significant heavy rainfall event for Canterbury. Heavy rain also for parts of central New Zealand, and severe gales for the South Island west coast. A complex low pressure system over the Tasman Sea is forecast to move slowly southeastwards across northern and central New Zealand over the weekend, before moving away to the east on Monday. This system is expected to direct a strong and moist southeast flow across the South Island during this time, delivering an extended period of significant heavy rainfall to Canterbury, and severe gale southeasterlies along the South Island west coast. In addition, an associated front is forecast to move eastwards across northern and central New Zealand on Saturday, delivering a relatively short burst of heavy rain to some areas. This is expected to be a significant heavy rainfall event for Canterbury. A Red Warning for Heavy Rain is in force for the region south of Amberley, and an Orange Warning for Heavy Rain is now in force for the region from Amberley to Kaikoura. Dangerous river conditions and flooding are expected. Slips and floodwaters are likely to disrupt travel, making some roads impassable and possibly isolating communities. The Strong Wind Watch for Fiordland and Westland south of Hokitika has also been upgraded to a Warning for severe southeasterly gales.

CommentMetService SEVERE WEATHER WARNING at 8:42 pm Saturday 29-May-2021. A severe heavy rainfall event for Canterbury. Heavy rain also for parts of central and southern New Zealand, and severe gales for parts of the South Island. A complex low pressure system over the Tasman Sea is forecast to move slowly southeastwards across northern and central New Zealand over the weekend, before moving away to the east on Monday. This system is expected to direct a strong and moist southeast flow across the South Island during this time, delivering an extended period of significant heavy rainfall to Canterbury, and severe gale southeasterlies along the South Island west coast south of Hokitika. Severe southeast gales are also possible in Canterbury, especially about the coast and the Banks Peninsula. Another front is forecast to move onto Otago from the east during Sunday, delivering a period of rain, possibly heavy, to Dunedin and North Otago where a Heavy Rain Watch is now in force. This is expected to be a severe heavy rainfall event for Canterbury.A Red Warning for Heavy Rain is in force for the region south of Amberley, and an Orange Warning for Heavy Rain is in force for the region from Amberley to Kaikoura. Dangerous river conditions and flooding are expected. Slips and floodwaters are likely to disrupt travel, making some roads impassable and possibly isolating communities.

CommentMetService SEVERE WEATHER WARNING SEVERE WEATHER WARNING at 8:23 pm Sunday 30-May-2021. A severe heavy rainfall event for Canterbury. Heavy rain also for parts of Marlborough, eastern Otago and Southland, and severe gales for parts of the South Island. A complex low pressure system over northern New Zealand is expected to continue bringing widespread heavy rainfall into the Canterbury region, which remains under a Red Warning. Heavy rain is also forecast for Marlborough about and south of Kaikoura where an Orange Warning remains in force. A period of heavy rain is also possible about eastern parts of Otago and Southland where Heavy Rain Watches are in place. This low pressure system is forecast to move away to the east of the country on Monday. In addition, severe gale southeasterlies are expected along the South Island west coast south of Hokitika, and also for the Canterbury coast north of Ashburton, including Banks Peninsula. The remainder of Canterbury remains under a Strong Wind Watch, while southern parts of Marlborough are also covered by a Strong Wind Watch. This is a severe heavy rainfall event for Canterbury. Dangerous river conditions and widespread flooding are ongoing. Slips and floodwaters are disrupting travel, making some roads impassable and isolating communities. Further power outages are also likely.

CommentMetService SEVERE WEATHER at 10:21 am Monday 31-May-2021. A severe heavy rainfall event for Canterbury. Heavy rain also for parts of Marlborough. Severe gales for parts of the South Island. A humid southeast flow is expected to bring further heavy rain to parts of Canterbury, which remain under a Red Warning, although rain is easing or expected to ease during the course of the day. A heavy rain Warning (orange)also remains in force for Marlborough about and south of Kaikoura. In addition, severe gale southeasterlies are expected along coastal areas of Canterbury about and north of Banks Peninsula this morning, while a Watch remains in force for coastal areas of Marlborough. This is a severe heavy rainfall event for Canterbury. Dangerous river conditions and widespread flooding are still ongoing in some areas. Slips and floodwaters are disrupting travel, making some roads impassable and isolating communities. Further power outages are also likely.

CommentMetService SEVERE WEATHER at 8:12 pm Monday 31-May-2021. Red Warning for mid-Canterbury now lifted, but an Orange Rain Warning remains in force for the far north of Canterbury and southern Marlborough. The rain has now eased to showers across much of the Canterbury region, and the Red Warning for Heavy Rain is now lifted. However, an Orange Warning for Heavy Rain remains in force for Canterbury about and north of Cheviot, and Marlborough about and south of Kaikoura until midnight tonight (Monday), with rain then easing to showers in this area. Any remaining showers through Canterbury and southern Marlborough should clear by early Tuesday afternoon, and no further rain is expected for the remainder of the week. Please be aware, following the Red Warning for Canterbury, rivers will remain swollen for some time. Floodwaters will also take time to recede, so please continue to follow advice from local authorities, civil defence and emergency services.

Canterbury

FloodingFlooding at Canterbury
Comments:

Declared EmergencyA region-wide State of Local Emergency was declared by the Civil Defence Emergency Management Group. This remained in place for Ashburton, Selwyn, and Waimakariri districts until 11 June, but was lifted elsewhere about 5 June.

CommentSome parts of the Canterbury floods were so extreme that they were only expected to happen once every 200 years. During the floods Mt Somers recorded its largest 48-hour rainfall ever, with 526 mm. Rainfall stations nearer to the coast (Ashely, Oxford, Darfield, and Methven) recorded 48-hour rainfall amounts that would be expected about once every 50 years.

CommentOn 1 June the event was declared a medium-scale adverse event for the Cantterbury region, which provided $500,000 in government funding for recovery measures for the region.

CommentThe flooding situation was most severe in the mid Canterbury, Ashburton and Hinds areas, particularly at Ashburton Forks and Thompson’s Track. Rivers in the upper parts of those catchments were flowing very high, with gauges recording some of the highest volumes ever measured.

Affected LifelineState Highway 73 from Springfield to Castle Hill was closed due to slips and flooding. State Highway 79 from Fairlie to Geraldine was also closed due to flooding.

EvacueesPeople were evacuated from Springfield, the Upper and Lower Selwyn Huts, and Peel Forest.

CommentFederated Farmers reported there had been multiple rescues of farmers and other members of the public, as well as stock losses. In addition, it was anticipated that winter feed would be in short supply over the coming months, as a lot of it had been washed away by the flooding.

Affected LifelineMany roads, including some sections of state highways were closed.

CommentMore than 70 schools, kura, and early learning services in Canterbury were closed.

CommentThe Ashburton District Council asked residents to boil their water used for drinking and food preparation.

FloodingFlooding at Ashburton
Map Location: -43.902384 171.736416
Comments:

Declared EmergencyA State of Emergency was declared in Ashburton. Ashburton activated its Civil Defence Emergency Operation Centre.

DamageThree bridges in the Ashburton district collapsed or were washed away.

The Ashburton Bridge on State Highway 1 was closed about 8am on 1 June after motorists reported they could feel it slumping underneath them. One section of the bridge had slumped by about 10cm. The bridge closure meant there was no alternate route to the south of Ashburton, as all other road options were closed. Typically 21,000 vehicles go over the bridge on a weekday, and 30,000 on a weekend day. The bridge reopened for light traffic late on 1 June, and for heavy vehicles on 3 June.

CommentAshburton recorded more than double its monthly average rainfall for May within a 24-hour period.

CommentAshburton College was closed on the advice of Civil Defence.

FloodingFlooding at Timaru
Map Location: -44.398445 171.255200
Comments:

Declared EmergencyA State of Emergency was declared in Timaru.

CommentThere were multiple road closures in the local area.

CommentCivil defence centres were opened in Timaru, Temuka, and Geraldine.

FloodingFlooding at Christchurch
Map Location: -43.531120 172.636147
Comments:

Affected LifelineSurface flooding in Christchurch knocked out power to several hundred homes, and closed a number of streets.

References

Insurance Council of New Zealand (https://www.icnz.org.nz/natural-disasters/cost-of-natural-disasters/)
Meteorological Society of New Zealand (Inc.), Newsletter 165, Winter 2021.
Meteorological Society of New Zealand (Inc.)
Headline: Canterbury flooding: Christchurch roads closed by waters.
www.radionz.co.nz, 30 May 2021.
Headline: Live Canterbury flooding updates: Thousands of homes at risk.
www.radionz.co.nz, 30 May 2021.
Headline: Canterbury flooding: Thousands in Ashburton prepare to evacuate.
www.radionz.co.nz, 31 May 2021.
Headline: Live Canterbury flooding updates: Bridges collapse, hundreds of homes evacuated.
www.radionz.co.nz, 31 May 2021.
Headline: Canterbury floods: Rain to ease in Southern Canterbury but heavy rain warning still in place.
www.stuff.co.nz, 31 May 2021.
Headline: Live Canterbury floods: Rain easing, river levels dropping.
www.radionz.co.nz, 1 June 2021.
Headline: Canterbury flooding: Ashburton Bridge on State Highway 1 closes.
www.radionz.co.nz, 1 June 2021.
Headline: Canterbury flooding: Adverse event declared in region.
www.radionz.co.nz, 1 June 2021.
Headline: Ashburton Bridge reopens for light traffic.
www.radionz.co.nz, 2 June 2021.
Headline: Ashburton Bridge to open to heavy vehicles today - NZTA.
www.radionz.co.nz, 3 June 2021.
Headline: Canterbury flooding: State of emergency to continue for a week.
www.radionz.co.nz, 4 June 2021.
Headline: Some of Canterbury’s floods labelled a one-in-200-year event.
www.stuff.co.nz, 14 June 2021.