How to See a Tornado on Radar

If you are new to reading a radar, let us give you a quick meteorology 101. The reflectivity is the prettiest and most familiar part of the radar. It shows the intensity of precipitation in a general vicinity. The darker the reds and yellows, the heavier the rain and the better chance you have of seeing hail.

However, the most useful part of a radar during a tornado outbreak is the Doppler radar or a radar dual-polarization radar. It can see into the clouds, what kind of stuff is in there, and what direction everything is going. The velocity tells us in what direction and at what speed the hydro-meteors or the water droplets in the clouds are moving. The greens show stuff going towards the radar, and the reds show stuff going away from the radar. Anytime there is stuff going away from and towards the radar in a close general vicinity, that means there is some rotation.

In a close-up, you can see the greens and the reds close to each other, which can indicate the presence of a tornado. However, in a situation like this, where there is a lot of convergence between those inbounds and outbounds, tornadoes can pop up anywhere along that portion of the storm.

The correlation coefficient is located at the bottom right side of the radar. It scans the cloud and tells us that most of everything in this cloud is about the same size. If there are oddly shaped stuff, bricks, wood planks, shingles, and tree limbs in the clouds, it does not correlate with the raindrops, which results in a drop in the correlation coefficient. This means that there is debris in the clouds that will likely fall somewhere as the tornado continues to move through.

Whenever there is rotation or the likelihood of a tornado, mostly, what is looked at is the velocity. The radar sends out beams of data and receives them back to know how fast the moisture or the hydro-meteors in the air are going and in what direction. The green is stuff going towards the radar, and the red is stuff going away. The brighter the color, the faster it is moving. Whenever there is an area where there is a lot of green and red close to each other, that can indicate that there is some rotation there.

If you are in an area where there is a tornado warning, it is advised that you do not pay too much attention to the intricacies of how a radar works. It is best to get to your safe spot immediately.