Winter Storm Kronos has formed in Texas and will affect the Gulf Coast today. The name was bequeathed because the storm is producing winter precipitation unusually far south; a storm of this magnitude would barely be worth a mention in the midwest or northeast. Some kids will see snow for the first time, thanks to Kronos, but the effects will be limited and minimal compared to many storms this winter.
The Jet Stream
The jet stream, a westerly flow of air in the middle levels of the atmosphere, is a result of a temperature gradient (difference in temperature) from north to south at the surface. This winter, the gradient has been strong, with the polar vortex delivering arctic air far south, and the jet stream has been vigorous. Ripples in the jet stream spawn storms, and the temperature gradient provides the fuel in the form of potential energy. Some of the storms have been powerful.
The jet stream normally has a core of strongest winds, and ripples in the jet stream produce storms in the path of the core. When the core of winds is across the more northern latitudes, we call the weather pattern high latitude zonal flow. When the core is farther south, we call the flow low latitude zonal.
A Split in the Westerlies
Occasionally the jet stream divides so that there are two cores; this is known as a split in the westerlies. Ripples can occur in either core, but since the potential energy is shared, the storms produced are not usually intense. This is the case with Kronos, which formed in the southern branch of the jet stream during a split in the westerlies.
Kronos and the Alberta Clipper
At the same time as Kronos formed, an un-named Alberta Clipper, the result of a ripple in the northern branch of the jet stream, entered the northern plains. The two systems shared the energy in the temperature gradient, and neither is very strong. Normally each branch’s storms will follow a unique track. Sometimes, however, the two will merge on the Atlantic coast and produce a vigorous nor’easter. It’s the same as two ocean waves overlapping to make one larger wave.
Where Will Kronos Go?
There is some freezing rain and snow in southern Texas, an area that rarely experiences such conditions. As Kronos heads east, it will affect coastal areas of the northern Gulf of Mexico, but much of the bad weather will stay over the water. Kronos will never get a chance to combine with the no-name Clipper to its north, unless that meeting happens far out in the Atlantic.
Stormy Weather: The Pattern Continues to be Conducive for Storms
The weather pattern that has been in place over north America for more than a month will continue for at least another week with the split in the jet stream healing, and there is the possibility that another named storm could emerge, probably on the southeast Atlantic coast. After that, there are indications of a change in the pattern, with the polar vortex flattening out east to west; the new weather regime will lock the arctic air in Canada and allow a moderation of the intense cold that has gripped the eastern half of the United States.
Winter Storm Kronos: Enjoy the Snow, Texas
The snow in Texas will not last long. By Sunday temperatures should be back above normal and the snowmen of Texas will have melted in the 70 degree warmth.
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