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.

Matthew and Nicole -- the no-name storms -- come and go

They were named Matthew and Nicole, but we didn't get much of a chance to get to know either one of them.

As was mentioned here as an upcoming possibility a week ago, the western Gulf of Mexico yielded a tropical system late last week. Matthew was never more than a weak tropical storm, with winds around 40 mph, but it did bring some flooding rains to Louisiana.

Nicole, located in the open Atlantic near Bermuda, didn't even become a tropical storm. It was a subtropical storm, yet the National Hurricane Center gave it a name on the speculation that it could become a tropical storm.

A subtropical storm is a low pressure area over the ocean that shows both tropical and non-tropical characteristics. That is, it has at least some sort of internal "warm core" where convection is being fired primarily from ocean heat, and also elements of more typical "cold core" low pressure area being spun by the temperature differences in air masses.

In the early 1970s, meteorologists tagged subtropical storms with a curious name: "neutercanes." At that time, hurricanes were all given female names, so somehow these hybrid storms were "neuters." Wisely, the National Hurricane Center ditched this term within a few years, and it didn't stick.

The National Hurricane Center will sometimes elect to give a subtropical storm a name if its winds reach 40 mph -- the threshhold for a purely tropical system being named a tropical storm -- and if there is an expectation that the storm may develop into a true tropical storm in time.

This was the expectation with Nicole, but it didn't pan out. Unlike a tropical system, which pulls its energy from the condensation of warm tropical moisture drawn aloft, Nicole owed more of her spin to the presence of a cold upper level low aloft. Tropical systems develop much better when there is a high pressure system aloft, providing calm winds and a means to evacuate the low level rotating winds away from the storm's core.

Subtropical storms differ from extratropical storms. If a tropical or subtropical system moves inland or over colder water and converts into a regular low pressure area, it is called extratropical. Depending on the weather pattern they move into, tropical storms and hurricanes have varying degrees of success in converting to extratropical lows. Some just fall apart or disintegrate, while others can rev into extratropical low pressure areas with winds almost as strong as the original tropical system.

One tell-tale sign is the pattern of moisture around the system. Heavy rain and thunderstorms are tightly wrapped around the center of a tropical system. In extratropical storms, the moisture streams much farther from the center of circulation, and often takes on a "comma" shape.

Matthew is an extratropical low moving across Arkansas. Its rains have become diffused over a wide area and its surface winds nearly non-existent, but we could get some showers from the remnants of Matthew by midweek when a cold front pushes through. It will really just be little more than a street sweeper pushing some remains of confetti off the curb. Matthew never had a really tight core to begin with. It's no Jeanne or Frances, that's for sure.

As for Nicole, the subtropical storm is expected to become an extratropical storm and may even get pulled into another regular low pressure area. Nicole could give New England some rain, but it probably should have never been named in the first place. It's a storm that deserves anonymity.