Usually, the prevailing south-westerly wind would take the ash cloud away from Europe and over the polar region, but a high-pressure area is bringing it over Europe, where it is sitting and barely moving as the ash spreads.

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There was no moon, and under the low cloud cover a brisk unseasonable wind ruffled the old Norwegian maples that lined the street and dropped a fine rain of spring buds on my shoulders and in my hair.

NEWYORKER: Wakefield

Then he was gone, with a roar and a cloud of blue smoke, which the wind carried straight to us.

NEWYORKER: Hand on the Shoulder

Forecasters have said changing wind patterns made it hard to predict the cloud's exact path and concentrations would vary between regions.

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