Our First Shot of Severe Weather Moving In

Wednesday to bring many of us our first batch of severe weather.

The months of April, May and June are the most active months of the year for severe weather in the United States, and without missing a beat, the Sioux Empire’s first chance at severe weather in 2015 will come on April 1.

The Storm Prediction Center has outlined the center of the United States in a “slight risk” for severe weather on Wednesday, stretching from southwest Minnesota and into western Oklahoma.

If we take a closer look at the threat, we see that includes most of northwest Iowa, southwest Minnesota, southeast South Dakota, as well as northeast Nebraska. Areas inside the orange polygon (below) should be on alert for severe weather during the afternoon hours on Wednesday, especially after 3 p.m.

The primary threats with these storms will be large hail and strong wind gusts. However, in the early development of these storms, if they are more of a cell than a line of storms, there is the potential for an isolated tornado.

When forecasting severe weather, we look for the acronym S.L.I.M.: Shear (change in wind speed or direction), Lift (something to move the air upward), Instability (energy), and Moisture. It looks as though we will see enough of each category to bring us some severe weather. The very warm weather to the southeast will provide us plenty of energy (1st picture below), which lines up exactly with the areas with the highest moisture (2nd picture). A cold front will move through during the afternoon, which will provide us with the lift we need to get some of those storms going.

While Sioux Falls is in the risk, I expect most of the action to take place farther to the south and east after the storms get going. Most models have the storms firing up after the 3 p.m. hour as a cold front moves into the southeast area, but if some spots reach the upper 70s before then, we may see some storms fire a little earlier.

The bad news is also that we will likely miss out on most of the precipitation that will come with this system. It looks as though the heaviest of the rain will fall in northwest and western Iowa as the system continues to develop and move east throughout the evening,

For those of us that are hoping for more moisture, it looks like we will have to wait until early next week when our next real disturbance is set to move through. Early indications show some light to moderate showers Monday and into Tuesday, with some places farther north seeing a chance for some snowfall as well.

We’ll take it, because most of us are one to two inches below normal on precipitation to start the year! Stay safe out there on Wednesday and make sure you “LIKE” us on Facebook and “Follow” us on Twitter as we will be posting all the information you need to know if the storms do become severe!

-Brandon Spinner
Chief Meteorologist