What's An Ice Storm Doing In Atlanta?
The entire nation has watched in amazement as historic weather events unfolding in the south this week. A winter storm brought ice and snow from Texas to the Carolinas, areas not accustomed to winter weather. The cities of Birmingham, AL and Atlanta, GA are at a standstill due to the fact that they just are not prepared for an ice storm . Freeways have turned into parking lots, and some commuters in Atlanta have been stranded on the roads for over 24 hours, due to the sheer number of vehicles clogging the highways. Government officials are frantically working to reach motorists and clear the roads. The governor of Georgia earlier today, asked that all semi-truck drivers divert around the entire state, because of all the semis already stuck and unable to move on the ice-covered roads. Vehicles abandoned Tuesday evening, still sat on an exit of Highway 285 in Dunwoody, GA on Wednesday. Photo credit: Associated Press
A number of businesses, fire departments, and schools stayed open overnight to provide a warm place to sleep for stranded motorists, students, and parents trying to pick their children up from school. There have also been reports of a number of Good Samaritans passing out hot drinks and food to those still caught on the impassable roads. Many towns and cities in the south simply don't have the equipment to handle a winter weather emergency. They don't need to, as snow and ice typically remain far north of the Deep South. Good Samaritan Matthew Miller offered free peanut butter and jelly sandwiches, cereal and hot drinks to drivers stuck in traffic on Atlanta's Southbound Connector on Wednesday. Photo credit: Associated Press
The southern United States is classified as a Cfa climate, or humid sub-tropical climate. Their winters are very mild, and characterized by highs in the 50s-60s, and lows in the 30s-40s. A winter storm like what happened this week, is exceedingly rare. So what is responsible for their typically mild winters? Three things, all of which involve, location, location, location. One is simply the latitude at which the south sits, the polar jet stream, and the sub-tropical jet stream. Normally, the polar jet remains well to the north of places like Atlanta, GA and Birmingham, AL. It is the sub-tropical jet that is normally located near the southern United States, that dictates their warmer climate. But, these two jet streams do not have a set location, their position around the globe fluctuates up and down, interacting with, and affecting the storm systems moving across the United States.
As this polar jet meandered far south of its typical range , temperatures fell below normal, setting the stage for a historic snow and ice event, as the winter storm system moved across the southern United States. Had the polar jet remained to the north, as it usually does, places like Atlanta would have seen only rain, instead of ice.