Major Severe Weather Outbreak Today in Middle of Country

A significant outbreak of severe weather is expected today across the middle of the United States.

First let me say that this system will arrive in Alabama on Monday afternoon and evening, but it will not have the same level of danger when it gets to us. We will have decent instability on Monday, and there will be sufficient wind shear for organized thunderstorms, some of which will become severe. But it will not be a major outbreak of severe weather for us. Having said that, we will be watching it closely because as we always say, when it comes to storms in Alabama, “Expect the unexpected.”

Today, the Storm Prediction Center has already posted its Day 1 Severe weather Outlook, which went into effect at 7 a.m. CDT, continuing until 7 a.m. Sunday morning.  It has a large slight risk, their standard forecast risk area, extending from northern Texas through Much of Oklahoma, Kansas and Nebraska into parts of South Dakota, southwestern Minnesota, western Iowa and Missouri.

Embedded within the risk area is a large area of enhanced risk, what they call a moderate risk, extending from Nebraska and Iowa to Oklahoma.  There are two bulls eyes inside this risk where there is a high risk of severe weather.  One covers much of Nebraska, including Norfolk, Lincoln and Omaha.  The other includes parts of Kansas and Oklahoma, including Wichita and Oklahoma City.

We already have a strengthening surface low this morning over eastern Colorado.  Strong upper level winds will help it to become very powerful as it moves northeastward today and by tonight, it will be moving northeast across Nebraska.  It will pull lots of warm, moist air northward from the Gulf of Mexico.  Dewpoints are in the middle and upper 60s over the southern Plains, waiting to be drawn northward by the low.  Moderate instability will extend northward to a warm front that will be lifting northward.  In addition, high winds aloft, at the jet stream level, will overspread the area later today, helping the storms to really explode.  The presence of strong winds in the lower atmosphere will give the storms lots of low level spin.

The result will be several tornadic supercells today across the risk region.

Then the event will transition tonight into a powerful squall line that will sweep eastward, producing a widespread threat for damaging winds and embedded tornadoes eastward to places like Sioux Falls, Kansas City and Des Moines.

Tomorrow, a lesser threat will move into the Arklatex from southern Missouri through much of Araknsas, western Louisiana and eastern Texas, as that powerful squall line should continue for much of the day and night. It should reach near Memphis and Alexandria LA by the predawn hours Monday. Then we will deal with it later in the day on Monday.

Category: Alabama's Weather, Severe Weather