Tornado Risk for Louisiana... Again
Powerful thunderstorms, some capable of spawning tornadoes, will soon fire from Texas to Oklahoma then shift eastward into hard-hit Louisiana, the Florida Panhandle, Georgia, Tennessee and perhaps as far northeast as Ohio.
A multifaceted storm will target the middle of the nation today into Wednesday with snow and flooding rain in addition to the severe thunderstorms.
High winds, not associated with thunderstorms, were already causing damage and kicking up dust in California and neighboring states. This is a sign of a very dynamic system, much more so than the system that hit the south central states this past weekend.
The setup later today into Wednesday will bring the threat of multiple tornadoes. A few of the tornadoes could even be strong.
Along with the threat of tornadoes is the likelihood of multiple incidents of large hail, damaging wind gusts, lightning strikes and flash flooding.
Today/Tonight
The area of concern for today into tonight lies from Dallas and Oklahoma City eastward to Springfield, Mo., Memphis, Tenn., and New Orleans.
Severe Weather Expert and WeatherData.com CEO Mike Smith is concerned that many of the storms will occur after dark Today.
"Some of the forecast tornadoes may be especially dangerous because people will not realize the storms are there until they are at the doorstep," Smith said.
The waves of storms will progress to the east, crossing the Mississippi River and igniting to the south toward the Gulf Coast.
South and west of the main center of the large storm system, strong winds will roar in the clear air over parts of New Mexico and western Texas. The winds will be strong enough to kick up dust, knock over high profile vehicle and down power lines. The winds could also spread wildfires.
Wednesday and Beyond
Tuesday night into Wednesday, the greatest risk of tornadoes will be in the Deep South from Louisiana to the Florida Panhandle, including much of Mississippi and Alabama. However, severe thunderstorms could occur as far north as the Ohio Valley.
Like most others, this storm system will eventually reach the Atlantic coast. For much of this area the major threat may be flash and urban flooding.
At least a few of the storms along the Atlantic Seaboard late in the week could be heavy and gusty. However, it is certainly possible that severe weather rolls along part of the I-95 corridor from Florida to Maine.
Meteorology of the Outbreak
A surge of warm, moist air will roll northward over the lower Mississippi Valley and into the southern Plains today. At the same time a sweep of dry air will attack from the west.
The combination of these two clashing air masses along with a developing surface storm and jet stream energy from above will allow severe thunderstorm to develop.
The shifting of winds with height will cause some of these thunderstorms to rotate. The rotation, in turn, can yield a tornado.
In more technical terms, the storm system will take on what meteorologists call a "negative tilt."
Intensifying systems of this nature have a long history of producing multiple tornadoes because of the way they are stacked through various layers of the atmosphere.
They are indicative of a cold air invasion high in the atmosphere, which allows the rising column of air within the thunderstorms to always be warmer than its surrounding environment.
[ Bericht 3% gewijzigd door #ANONIEM op 08-03-2011 17:00:38 ]