DISCUSSION: While parts of the Northeastern United States experienced a powerful coastal snowstorm, a strong upper-level trough brought the coldest air of the season along with heavy snowfall to Central and Southeastern Europe. Very cold air from Northern Russia was filtered down into the region, which brought temperatures as cold as -40°C in some spots! The winds located high up in the atmosphere at the 250hPa level (~34,000 feet which is roughly 10,300 meters), were responsible for bringing the cold air South into Southeastern Europe. The winds this high up in the atmosphere are known as the Jet Stream and they move all weather systems across the globe. The cold air also brought impressive snowfall amounts to many across the continent, especially in Italy.
Just like here in the United States where we have Lake-Effect snow, which occurs when cold air moves over the warm Great Lakes and can drop feet of snow over several days, Italy experiences Sea-Effect snow, thanks to cold polar air moving over the relatively warm Mediterranean Sea. When cold air moves over a warm body of water, warm air is forced to rise where it then cools and condenses and drops snow downwind of the body of water. For example, in the United States when a brisk Northwest wind develops in the wake of the passage of a cold front over Lake Erie, heavy Lake-Effect snow bands develop over the town of Erie and persist until the winds either decrease or shift direction. The same thing occurred in Italy last week when the cold air moved over the Adriatic Sea from the North and dropped the heavy snowfall to the South which is Italy’s Eastern coastline. Some places higher in elevation recorded over 200cm of the white stuff! That is nearly 6.5 feet, that is more than enough snow to bring cities and towns to a halt. Snow was even reported as far Southeast as Greece and even Istanbul, Turkey.
The cold air is not set to retreat anytime soon, making cleanup efforts very difficult because when temperatures are that cold frostbite can develop in just minutes on any exposed skin. Temperatures should hopefully moderate towards normal by this weekend, but looking even farther into the future another cold wave is set to pummel Eastern Europe as we head into early next week. Stay warm out there our fellow European followers!
To learn more about other high-impact weather events from across Europe, be sure to click here!
~ Meteorologist Jake Keiser