Kevin Myatt

Latest entries from the Weather Journal blog

• Weather Journal taking a long break
• Yes, there's still an Atlantic tropical season going on
• Freezing temperatures likely tonight

About Kevin

Kevin Myatt grew up in Arkansas to the tune of tornado sirens and the rhythm of hailstones, aspiring to be a meteorologist before his studies and career were turned to journalism instead. Though he often chases storms, he prefers living in the cooler, more tranquil weather of the Blue Ridge. He moved to Roanoke in 1999 to take a job on the copy desk of The Roanoke Times; writing headlines and editing copy is his principal work for the newspaper today.

Each May, Kevin assists Pulaski County High School / Virginia Tech meteorology instructor Dave Carroll in leading college and high school students to the Plains to observe severe weather firsthand. The accounts of many of his storm chases can be found here on the storm chasing page of his weather blog on roanoke.com.

Kevin was an editor for "Hurricanes and the Middle Atlantic States," a book written by D.C.-area weather enthusiast Rick Schwartz and published by Blue Diamond Books that documents hurricanes striking the mid-Atlantic states since colonial times.

The Weather Journal column began in 2003 and appears on Friday's Virginia section front in The Roanoke Times. The Weather Journal blog began in 2006 and follows weather day-by-day between the larger columns.

Could we get a snowy surprise in March?

A big storm system blows up in the Plains states. Arctic air amasses in eastern Canada and western Alaska. The entire weather pattern over the continental United States is controlled by what's going on over the northern Pacific Ocean.

This arrangement has been the default setting for the 2006-07 winter. It was like that in late fall, it quickly returned to that from mid-December to mid-January, and now it's back at it again.

A massive low-pressure system in the central Plains will track northeast toward the Great Lakes over the weekend, spreading heavy snow to the northern Plains and western Great Lakes, regions that haven't seen a lot of snow this winter. It will spread heavy rain and possibly severe thunderstorms from the southern Plains to the southeast coast.

In between, we will see mostly rain. There could be some freezing rain or sleet, especially north of Roanoke, as the rain catches up to a bit of colder air Sunday morning. But it shouldn't last long as milder air streams in ahead of our next cold front.

Events over the Pacific Ocean have driven our weather pattern this winter. When there has been a strong low-pressure system high in the atmosphere there, we have had milder weather, as we have most of this past week and to a much greater degree through most of December and January. When there has been a large high-pressure system aloft over that region, it has dislodged cold air from Alaska and Canada southward, as it did from Jan. 17 to Feb. 19.

The pattern over the Atlantic Ocean really hasn't asserted itself much into our weather. Early in the winter, we saw a ridge of high pressure build in from Bermuda. That helped intensify the early-season warmth, but it was easily deflected when the Arctic air came knocking in late January.

Even more critical has been the northern Atlantic.

Cold air masses tend to circulate west to east around the north pole, with little movement south, unless there's a boulder in the stream forcing them in that direction. That boulder is frequently a large area of high pressure in the northern Atlantic.

That blocking high pressure hasn't happened most of this winter. Even early February's cold resulted more from the strong high-pressure system in the Pacific than from anything over the north Atlantic. Our cold air wasn't so much locked in by events downstream as it was continually reinforced by mechanisms upstream.

This may seem like weather geek semantics because it still got cold. But the implications on the storm track were huge, and largely explain why snow was scant.

Cold air masses moving southward either crushed storm systems to the south or, without the blocking high in the north Atlantic, simply slipped out to sea as storm systems arrived. Over and over again, the weather pattern failed to connect the Arctic air and storm systems moving through the southern U.S. in the correct way to produce a significant snowfall for our area.

So where does that leave us now?

Each time the Arctic air has banked in eastern Alaska and western Canada this winter, it has eventually come south and spread over the United States. It did so the first week of December, and most notably from late January to mid-February. We're waiting to see if it will do that again, perhaps to start March.

And now, for the first time, we have a significant amount of blocking in the north Atlantic. It will deflect this weekend's storm far enough south to dump snow on much of New England and threaten Northern Virginia with an ice storm. Earlier in the winter, these Plains storms were simply racing into Canada and drawing mild, moist air all the way up the East Coast.

The one last great question of this winter is whether the combination of blocking high pressure in the north Atlantic, a possible return of Arctic air and storm systems moving in from the Pacific will combine for an early March winter storm to cap a season largely devoid of winter storms in our area.

I have my doubts, and there is no solid indication at this time that anything of this nature will happen. But it is an intriguing possibility, and it would certainly seem to be a fitting ending to a weird winter.