Hurricane Sandy is four days – or maybe six days – from making U.S. landfall somewhere around New Jersey – or maybe northern Maine.
Hurricane forecasting has improved dramatically in the last half century – it wasn’t until 1988 that the National Hurricane Center even released 36-hour forecasts – but it’s still an inexact science confounded by the fickle ways of Mother Nature.
So how soon is too soon to start packing or panicking? The chart below shows the average accuracy of the Hurricane Center’s tracking of Atlantic storms over the last five years, from 12 hours to five days out. So for example, at five days out – the blue 120-hour line – the forecast was off by less than 200 nautical miles about the half the time and off by more than 200 miles about half the time.
Likewise, the green line shows that 48 hours out, the forecast track was off by no more than about 100 nautical miles 70 percent of the time. And the accuracy naturally gets better still as the time frame shrinks.
So where and when will Sandy hit? Who knows. But just in case, you might want to print out the chart so you have something to read by candlelight next week.