New technology makes tracking tornadoes easier

RICHMOND, VA (WWBT) - It's been quiet around here since April, but April was a pretty active month with 11 tornadoes hit the Central and Eastern Virginia.

When you watched our severe weather coverage, you saw us use technology you may not have seen. It's called radial velocity… a technical term but an invaluable tool to pinpoint the location of potential tornadoes.

When we show you First Warning Doppler Radar, you're used to seeing how the radar works by sending out a beam of energy that detects the presence of water droplets in the air.  The heavier the rain, the brighter the color.   Green means a lighter, more gentle rainfall while red means the heaviest rain.

Because of Virginia's warm and humid climate, thunderstorms here often produce very heavy rain and most of our tornadoes are hidden within a wall of water.

That's why our Doppler Radar is so important.  It can also see inside these thunderstorms and detect the strength and the direction that the winds are blowing within an individual storm cell.  That's where radial velocity comes in to play.

The colors on the radial velocity display are simply red or green.  Green indicates winds that are blowing toward the radar site and red is wind that is blowing away.  When you see the green and red very close together like this, it indicates strong rotation within the thunderstorm and a high potential for a tornado.

This area would be the most destructive part of the storm.  Pinpointing that location is critical in our efforts to show you where the potential tornado is and where it's heading next.  We can then show you what communities and even neighborhood streets could be in harm's way.

Technology is getting better every day and so are our viewers... We used to shy away from showing this on the air but we're doing it more and more to give you the best information possible.

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