The blizzard was forecast to arrive on Sunday evening. Then, in the wee hours of Monday morning. Then, for sure by 7am. Then, in the early afternoon. That's when it finally began to snow --- but at a rate far less than anybody had said.
Winter storm predictions by meteorologists around here almost always seem to be wrong in the same ways. Bad weather is anticipated to arrive earlier than it actually does, and to be more severe than it turns out to be. There are a number of natural reasons for this kind of bias. If you don't give warning and something really serious happens, people remember your mistake (especially if they're unprepared and get hurt). On the other hand, if you postulate a worst-case scenario and things aren't quite as bad, folks will be relieved and will tend to forgive your conservatism. Even more important: if you shout loudly about a dramatic event and it does come (more-or-less) on schedule, then you can use that somewhat-correct prognostication to enhance your reputation and get more attention (and more money) for your next forecast.
In the technological sphere does everybody recall the hypemeisters of the dot-com bubble? And even more guilty, the meta-hypersters who made their living writing about the next big big thing? They had a geniune talent for moving on --- for turning their spotlights on something else when their previous year's fair-haired child prodigies all came a cropper.
My favorite experience of how, even if the techno-soothsayers were "right" they were wrong, began in the mid-1990's when I visited a too-famous-to-mention-here high-tech consulting think tank. The in-house buzz was all about a marvelous new technology --- the DVD --- which would surely come to dominate the market for home entertainment from videotapes within one year, or at most two.
Or so they said. Reality was less nimble by almost an order of magnitude: it took most of a decade for the market to shift, and when that happened it was a far gentler transition than the genius-consultants had predicted ... just like yesterday's snowstorm.