Blizzards May be Just the Beginning of Stormy Weather Pattern
By Mel Fabrikant Saturday, February 09, 2013, 04:41 PM EST
The recent New England Blizzard of 2013 and a Plains blizzard this weekend may be just the start of a more stormy weather pattern.
Storms tend to move along a river of air high in the atmosphere, known as the jet stream.
According to Paul Pastelok, head of AccuWeather.com's Long Range Forecasting Department, "A westward trend in the overall northward bulges and southward dips in the jet stream are likely to send storms into the eastern states through the end of February."
The pattern will promote a southwesterly flow aloft in the East. At first glance this suggests a warm flow. However, such a flow will allow storms to grab more moisture from the Gulf of Mexico.
"The atmosphere appears to be building a pipeline of storms with Gulf of Mexico moisture available," Pastelok said.
A large southward dip in the jet stream, will favor a large pool of cold air over the Southwest, Plains and Midwest.
"At the same time, near the surface, cold high pressure areas can slip into the Northeast from north of the Great Lakes, beneath the flow aloft, setting the stage for more wintry precipitation when some of the storms are passing through," Pastelok added.
The cold high pressure areas offer the necessary resistance to the warm air brought northward by the jet stream and the individual storms. Such a pattern can bring multiple big storms, with a sizable amount of freezing or frozen precipitation this time of the year.
The pattern will not mean that every storm will bring snow, ice or a wintry mix to all areas during every storm, but it will open the door for more opportunities for heavy wintry precipitation farther south, including portions of the southern Plains, Midwest, mid-Atlantic and New England.
Much of New England and Long Island were buried with a general one to two feet of snow from the recent blizzard. However, many areas in the coastal mid-Atlantic have received well less than half of their average snowfall for the season, while surpassing the half-way mark of the winter.
"We are seeing a westward shift in a ridge of high pressure over Pacific Ocean, which translates to a trough over the central states and a southwesterly flow aloft in the East," Pastelok said, "We anticipated this would happen, just that is occurring a few weeks later than we originally thought when making the seasonal winter forecast back in the fall of 2012."
More information on each of these storms will be made available as soon as possible on AccuWeather.com.
Early indications are one such wintry storm will track from the southern Plains Tuesday to the Ohio Valley Wednesday and part of the East Wednesday night.
A storm bringing blizzard conditions to part of the Plains this weekend, will turn eastward with an icy mix in some northern areas Monday. The pattern Pastelok suggested would begin to evolve more so after that storm moves by.
By Alex Sosnowski, expert senior meteorologist for AccuWeather.com