Thousands of people across the lower North Island were shaken awake before dawn on Saturday when a magnitude 4.9 earthquake struck off the Kāpiti Coast.
GeoNet recorded the quake at 6.34am on 5 September, centred about 30km north-west of Paraparaumu at a depth of 26km, and described the shaking as moderate. Within minutes its felt report form was filling up. By mid-morning 21,899 people had told GeoNet they felt it, one of the biggest public responses to any New Zealand earthquake this year.
That number is worth pausing on. Newswire pulled the felt report tallies for every earthquake of magnitude 4.3 or greater recorded anywhere in New Zealand so far in 2026, using GeoNet’s own quake search and felt report data. Of the 73 events that qualified, only one has drawn more reports than Saturday’s, the magnitude 5.9 shake near Taumarunui on 25 July, which collected 22,942. Saturday’s much smaller quake comfortably outranked the magnitude 6.3 earthquake that hit Fiordland on 16 July, which drew 18,531 reports despite releasing more than a hundred times as much energy.
The difference is people, not physics. A moderate quake under a corner of the country where half a million people live will always be felt by more of us than a large one under the Southern Alps.
GeoNet grades felt reports on the modified Mercalli intensity scale, which measures what people actually experience rather than how big the earthquake was. Of Saturday’s 21,899 reports, 10,756 were graded at intensity 4, or light shaking, and 5,915 at intensity 5, moderate. Another 4,741 came in at intensity 3, weak. At the sharper end, 455 people reported strong shaking at intensity 6, 18 reported severe shaking at intensity 7, and 12 reported extreme shaking at intensity 8. The strongest reports clustered on the Kāpiti Coast, in Wellington, across the Wairarapa and at the top of the South Island, with the felt zone stretching from Marlborough and Nelson up to the Central Plateau.
A Raumati South man told RNZ he heard it before he felt it. “I was asleep, but woken by a noise you could hear coming… like a close freight train,” he said. “Then a decent shake for about 10 seconds and a wobble. During the wobble, my phone alert went off, despite my phone being on silent. No damage, and I have felt stronger quakes here…”
An RNZ reporter in Lower Hutt said furniture began shaking against the wall in her house and neighbourhood dogs started barking, with the shaking going on for some time.
The scientists watching the instruments felt it too. GeoNet posted that “the earthquake was felt in our National Geohazards Monitoring Centre in Lower Hutt, who heard the quake coming and report it had definite primary and secondary wave arrivals, which makes the quake feel longer.”
That detail explains why so many people described a long, rolling shake rather than a jolt. GeoNet earth sciences seismologist Sam Taylor-Offord said the two wave arrivals would have been very noticeable to many of those who felt it.
“Often with earthquakes, people don’t feel the primary wave. It’s the smaller, faster wave. You might see it in like the rattling of glass or lights, but it’s the secondary wave that has a lot more of the energy, and that’s what people typically feel,” he said. “And when you feel both of them, it’s going to make the earthquake feel possibly twice as long, rather than just a jolt. It’s a real rolling motion.”
Taylor-Offord said the quake was very normal for an area that has a lot of earthquakes, and GeoNet did not believe there would be any aftershocks. If there were, he said, they would be unnoticeable.
The catalogue backs him up. Newswire counted every earthquake of magnitude 4 or greater logged by GeoNet over the past 12 months in the block of country running from Whanganui and Palmerston North south through the Kāpiti Coast, Wellington and the Wairarapa, across Cook Strait and into the Marlborough Sounds. There were 22 of them, roughly one every 17 days. Most were too small or too deep to make the news.
Saturday’s was the largest in that area since a magnitude 4.9 on 6 November last year, and the two are so close in size that they are effectively a tie. The last time the region produced anything above magnitude 5 was a magnitude 5.3 about 10km east of Eketahuna in January 2025. The busiest recent stretch by far was late 2016, when 58 quakes of magnitude 4 or greater struck that block in the seven weeks after the Kaikōura earthquake alone. There have been 17 so far this year, and 17 in all of 2025.
The phone alert the Raumati South man mentioned is worth a word of explanation, because it is routinely mistaken for a government service. New Zealand has no official national earthquake early warning system. Earth Sciences New Zealand, formerly GNS Science, has said as much, and the alerts that reach some phones seconds before the shaking come from Google’s Android Earthquake Alerts System, which uses accelerometers inside handsets rather than GeoNet’s seismometers. We looked at how that works in more detail after July’s Taumarunui earthquake.
For anyone who wants to see where Saturday’s shaking landed, we have published a breakdown of the felt reports for this event on our Paraparaumu quake page, and every recent New Zealand earthquake is plotted on the Newswire earthquake map.
An early morning fright that leaves the crockery on the shelf is the cheapest earthquake drill going. It is a decent prompt to check the grab bag, tie down the bookcase and make sure everyone in the house knows the plan.
Did it wake you up on Saturday morning? Tell us where you were and what it felt like in the comments below.
This article was written by AI, briefed to report the facts, hopefully without some of the bias people bring to the job 🙂
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