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.

Even with warmup -- we're progressing toward fall

It got to 91 degrees on Friday in Roanoke.

That is usually not a landmark event in a typical summer. But it was Roanoke's hottest high temperature of summer 2004, the first time it had gotten above 90 degrees.

Our "heat wave" was short-lived -- more a warm ripple than a heat wave -- as a cold front swooped in, rained some on our Saturday and then cooled us off for Sunday and today.

But that little burst of heat could be a precursor of how our August will end.

A high pressure ridge is building aloft over the eastern United States. It's the kind of development that, were it mid-July rather than late August, might portend a substantial heat wave. This late in the season, it might gives us at least a few summery days before meteorological summer ends on Aug. 31. (By the astronomical calendar, it drags on to Sept. 21.)

Historically, you can't write off summerlike weather yet just because we haven't had much of it so far. Records show that Roanoke Regional Airport has been 90 or above as late as Oct. 6 -- 91 in 1951, back in its Woodrum Field days. It's been 100 or above as late as Sept. 5 --101 in horribly hot 1954, a year when it also got to 89 as late as Oct. 13.

But while we could still see some hot weather, a prolonged late-arriving heat wave does not appear likely. Those early 1950s Septembers followed hot, dry summers that left the ground parched and the vegetation withered.

Also, it's doubtful the weather pattern will stagnate now like it would need to for a late heat wave. In fact, this shift from our stable summer pattern may itself be a harbinger of fall.

A upper-level low pressure system is crashing ashore in the Pacific Northwest this week, bringing cool, wet weather to an area that has had lots of unseasonable heat and drought. It's breaking through the high pressure dome that has been in control of that region this summer, the same high that has in turned helped funnel unseasonably cool air into the southward dip in the jet stream over the central and eastern U.S.

Just like you can do by snapping a garden hose, this downward bend in the jet stream over the Pacific Northwest is springing an upward turn farther east, hence our East Coast high.

But just as a bulge in a hose travels down its length, so will the high translate eastward. It's expected to slip out to sea later this week. The result will be that it will start turning the winds out of the southeast aloft on its clockwise circulation, and this will start building moisture later in the week for showers and thunderstorms. While it will become plenty sticky, the clouds and daily showers will inhibit any kind of really intense warmup. And the Pacific Northwest storm may affect us by the weekend or early next week.

When ripples in the jet stream travel across the country with regularity, it is called a progressive jet stream pattern. Though uncommon in winter when Arctic air masses can get lodged in one part of the country or another, and even more rare in summer when heat-dome high pressure areas can bring the weather pattern to a standstill, a progressive jet stream pattern is a common feature of spring and fall.

Storm systems enter in the west, cross the country and exit east as a new one enters the west. Sometimes it even gets to be such a steady cadence where one can expect rain, say, every 3 days, followed each time by a cool, dry day and then a warm, more humid one.

We're not quite to fall or a fall-like weather pattern yet, even though many mornings have felt just a shade above frosty lately. But this is certain: the days are getting shorter, the sun angle is getting lower. The sun's heat is less potent with each passing day.

That's a progressive pattern that will continue whatever the jet stream is doing.