Aotearoa Earthquake and Volcano Forecast Service

Aotearoa Summary. 19 April 2020 - 25 April 2020

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The quake period was busy early on.
Spaceweather arrived earlier than expected, driving two decent quakes, including the Te Anau 5.0.
Sadly, a forecast wasn't produced until late on 18 April...too late to catch the action and a mistake which ruined the forecast.
Slight Cape Campbell action was as big as quakes got after that.
Fluctuating solar wind streams and even a brief coronal mass ejection kept the forecasters guessing during the period.
The low confidence 21 April outlook for very weak or no quakes on 22 April was justified in the end.
Despite a brief strong aurora with the coronal mass ejection, spaceweather was very weak and not enough to drive any more local action through to 25 April.
18 April.
50km Northeast of White Island 4.8 12.54pm
Northwest Arm Te Anau 5.0 7.51pm
19 April.
Cape Campbell 3.7 3.17am
20 April.
Cape Campbell 3.6 3.35am

Forecast.
Magnitude 5 risk location is Dannevirke.
Magnitude 4 risk locations are Tolaga Bay, Kapiti, Northern Cook Strait, Murchison, Cape Campbell, Rolleston, Cascade River, Pyke River, Te Anau, Doubtful Sound.
Volcanos quiet.
The forecast period is likely to be extended.

Update. 20 April 12.30pm
18 April.
50km Northeast of White Island 4.8 12.54pm
Northwest Arm Te Anau 5.0 7.51pm
19 April.
Cape Campbell 3.7 3.17am
20 April.
Cape Campbell 3.6 3.35am
The forecast has become a shambles.
The forecasters couldn't pick the early arrival of spaceweather on 18 April.
Two strong local quakes had already passed through by the time a forecast was posted.
Spaceweather has now faded early and the Pacific is not very active.
More spaceweather is due to arrive but no confidence that it will have any strength.
Very difficult solar wind conditions during the period.
The quake period has probably ended in New Zealand.
Good location success on the biggest quakes during the forecast period although magnitude is low.

Update. 21 April 11.30pm
Local quakes remain quiet.
A strong but brief auroral burst last night is repeated tonight but hasn't lasted long enough to drive Pacific quakes.
Moderate Pacific volcanic activity is matched by a slight Taupo tremor increase.
Local quakes are likely to be very isolated or absent on 22 April.
More spaceweather is due to arrive for several days but is generally very weak with short strong bursts up to now and a nightmare to forecast at the moment.