How can a tornado form from an ordinary, summertime thunderstorm?

How can a tornado form from an ordinary, summertime thunderstorm?

JEFFERSON DAVIS COUNTY, MS (WDAM) - It was just another ordinary thunderstorm in western Jefferson Davis County until a brief tornado touched down Sunday night. The EF-1 tornado caused damage to several homes and was on the ground for about a mile.

How did it happen?

As a broken line of ordinary thunderstorms were moving northeast into western Jefferson Davis County, two outflow boundaries from earlier storms were moving though the county toward the storm. One boundary was moving south and another was moving west. The storms and the boundaries collided just after 6 .pm. Since everything was moving in different directions, it caused a brief area of low-level spin in the atmosphere when they collided. This combined with a new rapidly forming thunderstorm produced a brief spin-up EF1 tornado that caused damage along Lucas-Warner Road.

Why wasn't there a tornado warning?

There was no tornado warning issued for this storm by the National Weather Service. The reason for this is because the radar only detected this brief spin-up for one scan. The next scan of the storm showed that the rotation had fell apart. The other reason is that it takes 1-2 minutes to generate and issue a warning.

Velocity Radar showing the brief tornado in Jeff Davis County at 6:22 p.m./CDT 7/10/2016

How common is it to miss a tornado?

It is very uncommon for a tornado to form without a warning being issued but unfortunately, it can happen.  It happens so infrequently that, it is a statistical anomaly. A similar style event happened in August 2015 in Covington County, just southwest of Collins.