End the Winter Blahs: 7 Indisputable Signs of Spring
Mares Tails
Thanks to random 60-degree MLK Days in St. Paul or a subzero St. Paddy's in Amarillo, it can be tricky to know when spring is finally on its way. So we've got seven unexpected but reliable ways to tell winter is over.

Clouds That Look Like Mare's Tails

"Spring weather is generally the most active and potentially violent," says Carl Young, meteorologist and member the TWISTEX tornado-hunting team featured on Discovery Channel's Storm Chasers. As warm fronts move in, high-altitude clouds form that look like mare's tails—or ropes of long, thin, wispy hair. These are ice clouds, and once the temperature really warms up, these clouds go the way of Frosty the Snowman and blow away.