Aotearoa Summary. 16 February 2016 - 24 February 2016

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Quake activity may increase.
Magnitude 4+ risk areas are East Cape, Bay of Plenty, Rotorua, Tokoroa, Wairoa, Urewera, Cook Strait, St Arnaud, Murchison, South Awatere Valley, Christchurch, Hunter Valley, Fiordland.
Volcanoes quiet.
The period may be extended.
See Facebook/Roary Arbon

Update. 16 February 1100 NZST.
16 February. Northwest of Auckland Island 6.2
Fiordland is added as a Mag 5+ risk area.

Update. 18 February.
The new forecast period has begun on cue with big quakes to the north and south of Aotearoa.
Increasing Fiordland to Mag 5+ risk does not mean that the risk is increased for Christchurch.

Update. 16 February 2130NZST.
Heavy quake driving conditions have set in.
Fiordland is raised to Mag 5/6+ risk.
Northwest Arm and North Fjord of Lake Te Anau are target areas.

Update 17 February 1030NZST.
17 February. South of Fiordland 4.6
Quake driving conditions remain strong today and for the next few days.
The forecast period will be extended.
North Fjord and Northwest Arm of Lake Te Anau are still the target areas for new quakes.
Previous forecasts for Fiordland have almost always proven accurate in time but this is the first forecast a specific area for Fiordland has been offered.
Te Anau location confidence = low.
Christchurch received a Mag 3.6 aftershock yesterday, the biggest since the Sunday 5.7.

Update 18 February 1230NZST.
17 February. Southwest of Stewart Island 4.6, Northwest of Auckland Island 5.0, Kermadecs 5.1, South of Ward 3.6, 3.5
18 February. Christchurch 3.7
North Wairarapa, Kaikoura Coast are added to Mag 4+ risk areas.
Christchurch remains at Mag 4+ risk.
Quakes are confirming the strength of the driving conditions.
Christchurch was hit by multiple Mag 2/3 quakes yesterday during the big Pacific push.
The Pacific is under heavy pressure today and for the next few days.
An update will be posted tonight fixing a date for the end of the period.
Note. The last day of any forecast period is often the most active.
More info on Facebook/Roary Arbon

Update 18 February 2230 NZST.
18 February. Christchurch 4.3, East of Gisborne 3.6
The forecast period is extended to 23 February.
Quakes may become stronger near the end of the period.
Christchurch people won't need this Service to tell them quakes are active at the moment.
Christchurch remains at Mag 4+ risk but may be quieter next day or two with more Mag 4+ quakes possible from Sunday.
There is some volcanic signature showing for Aotearoa. Possibility for a steam eruption White Island next few days.

Update. 19 February 2230NZST.
19 February. Northwest of Auckland Island 4.8, Kermadecs 4.8, Northeast of East Cape 4.1, Christchurch 3.8
All forecasted locations and magnitudes are unchanged.
Quakes dropped back slightly in Christchurch today.
A pickup on Sunday is still anticipated.
A minor undersea eruption may have taken place at Havre in the Southern Kermadecs. The outlook for a steam eruption at White Island is now past. The steam eruption may have already happened on 18 February.

Update. 20 February 2300NZST.
Quakes were high frequency but low magnitude today, meeting the forecast profile.
All forecast magnitudes and locations are unchanged.
Quakes are forecasted to become less frequent but higher magnitude tomorrow, building toward the end of the period.
Christchurch remains at Mag 4+ risk. Watch out for a relatively quiet day with a slightly bigger one later on.
Volcanoes quiet.

Update. 21 February 2100NZST.
21 February. Cook River 4.4
Cook River is added to Mag 4+ risk areas.
All other magnitudes and locations are unchanged.
Quakes started to pick up today but overall low magnitude.
Christchurch was quiet today with one apparently noisy quake.
Activity picked up strongly in the Bay of Plenty.
The Cook River 4.4 was on the Alpine Fault and demonstrates the strength of the quake driving conditions.Interesting behind the scenes results in the same fashion as the Wilberforce 6.0 last year which had a nearby Upper Rakaia Mag 4 location.
Watch out for a decline in frequency locally and globally but some bigger magnitudes.

Update. 22 February 2130NZST.
22 February. North Kaikoura Coast 5.0 (4.7USGS)
North Kaikoura Coast is raised to Mag 5+ risk.
All other magnitudes and locations are unchanged.
The mid afternoon North Kaikoura 5.0 was widely felt from Nelson to Wellington and beyond, fitting the forecast profile perfectly
Christchurch has been relatively quiet today, no Mag 4.
Quake driving conditions are high so big quakes are possible again tomorrow.

Update. 23 February 2200NZST
23 February. North of White Island 4.5
Quakes fell back everywhere today except Bay of Plenty.
All forecasted magnitudes and locations are unchanged.

Update. 24 February 0800NZST
Quake driving conditions were quiet overnight.
Lunar driving conditons were weak....no full moon quake.
Solar driving conditons were also weak so few quakes were recorded.
Solar conditions have changed this morning and strong at 8.10am.
Possibility for Mag 4+ quake in 23 February forecasted location areas.

Update. 24 February 1015NZST
Quake driving conditions are still moderately strong this morning.
An updated forecast map shows the same risk locations and magnitudes as yesterday.

Update. 24 February 1300NZST.
Quake driving condtions have been consistently moderate this morning.
These conditions are likely the late arrival of the forecasted 23 February conditions.
The only Kaikoura quake was Waima River 2.4, 10km south of Ward, 12.29pm, near low tide
Quakes in Mag 4+ risk areas are possible this afternoon.
Global conditions are quiet. Mag 6+ Pacific quakes possible.

Summary.
16 February. Northwest of Auckland Island 6.2,
17 February. Southwest of Fiordland 4.6, Northwest of Auckland Island 5.0, South of Ward 3.6, 3.5; Christchurch 3.7
18 February. Christchurch 4.3, Gisborne 3.6
19 February. Northwest of Auckland Island 4.8, Christchurch 3.8, Northeast of East Cape 4.1, Kermadecs 4.8
21 February. Cook River 4.4
22 February. Ward 5.0
23 February. North of White Island 4.5
24 February. Fiordland 4.2, Taumarunui 4.0
The forecast period started on cue with the big Auckland Island 6.2 and swag of Mag 4's south of Fiordland.
Day by day forecasting was attempted for Christchurch and stayed ahead of the action.
The addition of North Kaikoura Coast as a risk location on 18 February was a good choice. The 22 February Ward 5.0 was widely felt.
The forecast for the period was a great success but the forecast map got very messy with mistakes.
The addition of Cook River as a risk location on 21 February followed the Cook River 4.4 earlier in the day. The map shows it possibly the other way around. A new map should have been posted to avoid this confusion.
Overlaying old forecast areas with new outlooks onto the forecast map also created a confusing mess at Kaikoura.
Text cluttered the map...there were so many quakes.
The period 12-24 February was the largest widespread South Island quake activity observed by this Service in 4 years.
Activity may increase in March.



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