I was at a literary festival recently when an audience member asked the panel if they thought the short story would make a comeback in this country. I was surprised at the time because, as far as I'm aware, the short story has never gone away. The genre in Britain may not perhaps share the robust health it enjoys in North America, especially after the BBC revealed plans to reduce its short story programming. But all is far from lost. We have Helen Simpson, Dan Rhodes, Ali Smith: skilled short-story writers, all. We can now add Jon McGregor's name to this roll-call, with his generously titled collection, This Isn't The Sort of Thing That Happens to Someone Like You.

McGregor's short stories have appeared in magazines and journals, but are brought together here for the first time in book form. Fans of his novels, in which he has finessed his own inimitable style, won't be disappointed. They will find all the linguistic risk, the formal experimentation, the authorial compassion of his earlier works  and more.

McGregor's fiction resembles those fairy stories in which size and scale are unstable, except that it isn't his protagonists who can suddenly loom into giants, it's the workings of his plots. His debut, If Nobody Speaks of Remarkable Things, was a novel dedicated to how the tiny mathematics of human lives can have enormous consequences. He is a writer much concerned with the minutiae of existence; minor events in human lives assume, in McGregor's fictional world, collossal scale.

As the title of the collection suggests, the stories are peppered with events that come out of left field, with characters whose lives change in an instant, mostly for the worse. These are, in a sense, tales of the unexpected, but don't expect any supernatural pyrotechnics from McGregor: the changes of fortune are entirely grounded in the real world, things that could happen to any of us. The stories wrap themselves around the wholly disconcerting premise that catastrophes can rear up in anyone's life without warning.

There is the teenager who, on the way back from his first date, knocks over and kills a man. He buries the body in a field so that he can be with the girl, so that he won't lose the life that seems suddenly so precious. Elsewhere, a man is refused entry to his daughter's nativity play on the grounds of divorce and a restraining order, but he will not take no for an answer. A boy swimming in the shallows tells his friends that he'll be out in a minute but then gradually finds himself drifting out to sea.

The stand-out story, "Wires", opens with a shock that quite literally falls from the sky. A young woman, Emily, is driving along a motorway when she sees a sugar beet blow off the lorry in front of her and fly towards her windscreen. She has time, she observes, "to make a list of all the things she was having the time to think about  Item Seven was just, basically, wtf." She pulls over, her windscreen shattered, the sugar beet in the passenger seat, giving off "an earthy smell, like wet earth, like something rotting in the earth". A van pulls over and its occupants, two men, tell her they have called the police.

The story is, at this point, unsettling enough, but as Emily stands on the verge, considering whether to end things with her boyfriend, the reader realises the two men from the van aren't quite what they seem. The younger one is gripping her arm while the older is waiting for them on the other side of the embankment, at "the edge of the woodland".

Edges are important to McGregor. The whole collection is set in the fenlands of Norfolk and Cambridgeshire, those landscapes dominated by sky. The fear of flood runs throughout the book, and is personified by McGregor's most disturbing protagonist, in "If It Keeps on Raining". He is an estranged husband and father, keeping an eye on the rising waters of the river, "the swirl and turn of  driftwood and debris". He is building himself a tree-house, despite the mockery of others, so that he alone will survive when the floods come.

To the anxious literary festival audience member  and anyone else feeling downcast about the state of the short story today  I say, read Jon McGregor's new book. Its verve, its inventiveness, its sheer quiet audacity will reassure you that the short story is alive, well and reaching new heights.

 Maggie O'Farrell's most recent book is The Hand That First Held Mine (Headline Review).

The 30 fiercely imagined stories in Jon McGregor's collection share an extraordinary topophilia: each bears as its subtitle the name of a fenland town or village, and even in tales that range widely across space and time we never lose touch with the flat Lincolnshire landscape.

It is not just the locale that links these stories; hanging over them like the rain-heavy clouds that roll in from the North Sea is a sense of imminent catastrophe. The land is being eaten away by the waves, villages drop off the map, everything is shifting and uncertain: the perfect backdrop for McGregor's deceptively chatty but ultimately unsettling narrative voice. In "Supplementary Notes to the Testimony of Appellants B&E" (one of the most powerful pieces in the collection), we read that "this landscape can be disorienting, with many of the smaller paths and creeks not being marked on the map and tidal flows dramatically changing the topography within the space of a few hours". Like WG Sebald in the "undiscovered country" of Orford Ness at the end of The Rings of Saturn, we can understand why people in the fens might feel that Armageddon is rather closer than do those in the snug embrace of hills or within city walls.

Over the course of the stories, we start to see patterns, reflections in the floodwaters. Characters reappear suggestively, most often in the form of unnamed narrators and ghostly interrogative voices. In Even the Dogs (2010), McGregor's third novel, the harrowing story of the death of an alcoholic was told through a Faulknerian chorus of spectral spectators. The point of the disembodied narrative "we" was to drive the reader towards sympathetic identification with characters who might otherwise be beyond our understanding. It gave the novel an ethical rigour  although it was no rib-tickler. The stories in This Isn't the Sort of Thing, by contrast, are often very funny. But it's nervous laughter: McGregor never lets us relax entirely. In "Wires", we are comfortably settled in what feels like the start of a campus novel when things start to get very weird indeed. Likewise, he pulls the rug out from underneath us at the end of "We Were Just Driving Around", and performs a brilliantly black tailtwist at the end of "The Last Ditch".

The most obvious contemporary influence on these stories is the American writer Lydia Davis. It's not just the remarkable ventriloquism and genre-hopping playfulness; McGregor has clearly thought hard about the order of the stories in this collection and, as is the case in Davis's work, the narrative tempo of the individual stories feeds through into the rhythm of the book as a whole. The woman in "Close" looks at a Japanese garden and "wondered if there were hidden meanings to the arrangement which you were meant to decode".

The energy of these stories is driven as much by what is withheld as what is revealed; we are constantly left guessing, filling in blanks, looking for islands of stability. Subtly, the book knits us into its blackly apocalyptic sensibility, so that even those stories not dealing specifically with the coming flood carry a shiver of dread.

Sharp, dark and hugely entertaining, this collection establishes McGregor as one of the most exciting voices in short fiction. The fenland landscape may be flat and dreary; these stories are anything but.

Alex Preston's The Revelations (Faber) is published next month