Severe Storm Threat, Including Tornadoes in Central US

By Alex Sosnowski, Senior Expert Meteorologist for AccuWeather.com

AccuWeather.com reports a strengthening storm tracking from California to Michigan will bring a major severe weather outbreak, including the risk of tornadoes.

The potential for dangerous and damaging thunderstorms will reach over a large part of the Southwest Thursday and Friday and then Central U.S. Friday into Sunday, impacting tens of millions of people through the weekend.

The same storm system aiming to bring spotty downpours to California, drenching rain to parts of the Plains and snow to the high country in the Southwest will also have a nasty, dangerous side and will mark an end to the quiet weather over much of the nation in recent weeks.

The storm will be in the developing and strengthening phase as it swings inland from the Pacific Ocean, crossing Southern California through the end of the week.

According to Expert Senior Meteorologist Ken Clark, "Hail, flash flooding and locally gusty winds will accompany some of the storms over Southern California, Arizona Rim Country, southern Nevada and New Mexico Thursday evening into Friday."

The storms will impact the cities of Los Angeles, San Diego, Las Vegas and Phoenix.

Farther to the east, during Thursday afternoon and evening, warmer, more humid air will be forced to rise rapidly over a wedge of cooler air from northern Oklahoma and southern Kansas to northern Arkansas and southern Missouri, western Kentucky and western Tennessee. The result will be a zone of thunderstorms that can become severe at the local level with hail, damaging wind gusts and flash flooding.

The main outbreak of severe weather will commence Friday.

The area from the northern Texas Panhandle to western Oklahoma, western and central Kansas, eastern Colorado and south central Nebraska will be ripe for thunderstorm development Friday. During the afternoon and evening, the building storms are likely to produce large hail and damaging wind gusts, but they can also produce a few tornadoes.

Drenching, locally gusty storms will also continue to erupt farther to the northeast Friday, spreading as far east as the southern Appalachians during the day and as far north as central Minnesota Friday night.

The risk of damaging, life-threatening thunderstorms, including tornadoes will reach a peak Saturday afternoon and evening from southern Minnesota and southern Wisconsin to Iowa, northwestern Illinois, eastern Nebraska, eastern Kansas, northern and western Missouri, central and eastern Oklahoma, northwestern Arkansas and north-central Texas.

According to Severe Weather Expert Henry Margusity, "The potential from the storms spans the complete arsenal of violent weather ranging from large hail and flash flooding to damaging straight-line wind gusts and tornadoes."

Cities that could be hit by violent thunderstorms spanning Saturday afternoon and evening include Madison, Omaha, Des Moines, Rockford, Kansas City, Joplin, Tulsa, Oklahoma City, Dallas and Kansas City.

College and high school football games are only a handful of the activities that could be impacted by the severe weather threat.

The risk of potentially damaging and life-threatening weather conditions will continue into the latter part of the weekend.

Over portions of the Ohio Valley and Great Lakes, strong wind gusts, with and without thunder, are a possibility as a cool front plows eastward during Sunday. Chicago, St. Louis, Indianapolis, Louisville, Cincinnati and Detroit could experience squalls capable of knocking down tree limbs and power lines.

Farther south, slow-moving and potentially repeating downpours and locally severe thunderstorms may affect portions of central and northern Texas to part of the lower Mississippi Valley Sunday.

The pattern shaping up into this weekend is a classic example of the secondary severe weather season that occurs during autumn.

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