US equities futures are also deep in the red with the Dow Jones expected to open later today down as much as 1,200 points from 25,864.78. New Zealand's benchmark S&P/NZX 50 Index fell 2.9 percent today.
McIntyre said the sharp fall in the kiwi and Aussie currencies had triggered "stops," points that trigger automatic selling or buying.
"We haven't seen anything like this for a long time and the market's still trying to get to grips with what's happened," he said.
"Anything could happen from here and I don't think anybody knows what will happen," he said. European and US markets haven't had a chance to react and investors could see further volatility overnight, he said.
The number of known coronavirus cases has soared past 110,000 globally and deaths are approaching 4,000.
Italy is trying to quarantine some 16 million people living in its northern regions, the centre of its soaring numbers of infections, with mixed success. A further 133 deaths on Sunday brought that country's total to 366.
The number of confirmed cases in New Zealand remains at five, but 54 people working at a hospital on Auckland's North Shore have been asked to self-isolate after coming into contact with a person who has probably contracted the virus.
Late today, the Reserve Bank of New Zealand and the New Zealand Bankers' Association put out a joint statement saying the banks are ready to respond to the covid-19 outbreak, as the virus has been labelled.
RBNZ governor Adrian Orr said the banks' responses to his queries show they are prepared and "well attuned to any impacts on their customers' businesses, employment and incomes."
NZBA chief executive Roger Beaumont urged customers, particularly small to medium-sized customers, who have been financially impacted by the virus to contact their bank.
"Each bank will have their own credit policies and approach to providing assistance. It's important for affected customers to talk to their bank as soon as possible. That gives banks the best chance of offering assistance," Beaumont said in the statement.
Finance Minister Grant Robertson said he is preparing a business continuity package and is looking at providing tax relief.
The New Zealand dollar was trading at 95.81 Australian cents at 5pm in Wellington from 95.59 cents late Friday. It was at 47.77 British pence from 48.69, 54.73 euro cents from 56.19, at 64.03 yen from 66.79, and at 4.3307 Chinese yuan from 4.3906.
The bid price on the two-year swap rate rose to 0.7298 per cent from 0.6980 on Friday while the 10-year swaps sank to 0.9400 per cent from 1.0075 per cent.
