In both instances, the Met Office failed to predict the movements of the jet stream - the high-level wind that races round the world 10km above the surface.

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This is the so-called jet stream, the fast river of air that helps drive our weather, which interacts with the storm's updrafts to create a spinning column of air.

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The Oklahoma City area, including Moore, could continue to face storms during the morning due to a strong cold front positioned through the state and a strong low-level jet stream "plowing into it from the south, " Van Dillen said.

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The explanation for this lies with the "jet stream" - a ribbon of fast-moving air, up in the atmosphere.

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That means more melting ice in the Arctic, dumping fresh water into the salty sea and making a mess of the all-important Gulf jet stream, which makes northern U.S. habitable.

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The configuration of the jet stream, a band of high-altitude westerly winds, also contributes, although its current position, to the far north above the continent, is not uncommon for summer, according to Mike Brewer, a physical scientist with the National Oceanographic and Atmospheric Administration.

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According to a recent paper by Francis and Vavrus in Geophysical Research Letters, the preferential warming of the Arctic, with a concomitant decline in late-summer sea ice, results in a more meandering jet stream, which is why Sandy shifted westward, rather than being shoved out to sea by the normally strong westerlies associated with the jet.

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This is no comfort as the forecasts continue to be grim, but it is a measure of the complexity of the physics involved - how air moves in waves, why certain patterns form - that more than 60 years later scientists are still wrestling with the question of how the jet stream operates and what shapes it.

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