Weather Tidbits: Polar Vortex
The polar vortex is explored in this Weather Tidbits. The polar vortex is a large area of cold air aloft in the stratosphere that typically spins above the poles. A strong jet stream has large pressure differences that keep the jet stream straighter and keep the cold air trapped towards the north. This means the Arctic is primarily dealing with the cold; while the mid-latitudes are warmer than usual. However every other year or so, the jet stream becomes weak, and when it weakens, it becomes wobblier, allowing the cold air to plunge southward. This leads to cold air in the mid-latitudes and warm air into the Arctic.