Weather tracker: Early snowfall in New York and a storm ruins Christmas lights in Spain | Snow

Heavy snow fell this week in parts of New England. New York’s Central Park received a few inches of snow, while 8 inches was dumped on parts of Long Island. This is the first snowfall in New York since 2018.

New York narrowly missed widespread snowfall a few weeks ago. The low pressure system moved ever so slightly north of New York, allowing warmer air to enter. Meanwhile, upstate New York and other parts of New England were on the colder side of the system and received significant snow accumulations.

This week, however, the synoptic picture was different. Extremely cold air moved from Canada to the northeastern United States. Along with the cold air, a low pressure system began to move eastward. Since the cold air was already present over New York, any precipitation that fell was snow.

Southern Spain was hit this week by Storm Emilia. In the early hours of Tuesday morning, a tornado accompanied by heavy rain wreaked havoc in the seaside town of La Cala de Mijas, Malaga. The tornado swept through the town, destroying £67,000 worth of Christmas lights along the high street. The storm is estimated to have caused £500,000 of damage.

The tornado formed when warm, less dense, moist air rose, while colder, drier air sank. A process known as “wind shear” allowed winds at different altitudes, blowing at different speeds and directions, to create an invisible horizontal tube of rotating air. An updraft, created by rising moist air, lifted this air tube and changed its orientation vertically. This forms a “mesocyclone,” a rotating column of air within a storm. Cold, descending air facilitated downdrafts that wrapped around the mesocyclone, causing it to intensify and focus its downward rotation, providing the perfect conditions for localized wind gusts to reach 80 mph (130 km/h). Outside the tornado column, winds were strong but not capable of moving debris, highlighting the hyperlocalized nature of this phenomenon.