Lightning and thunder--nothing on the radar?

Question

Last night I was watching tv and saw tons of lighting outside. It was non-stop and there was also thunder. So I checked the radar to see what was coming--and there was nothing on the radar! The closest storms were probably 100 miles away. I thought maybe it was a fluke and maybe the radar wasn't updated so I checked a different radar and it didn't show anything either.

How could there have been thunder and lightning if the radar was clear?

Answer 1

If you hear thunder, then the thunderstorms were likely within 20 miles away. The Doppler radar will only detect moving objects above a certain size like precipitation that is falling from the sky if it is not in clear or fair weather mode. So two likely answers are either their was a problem with the radar and it was not detecting or recognizing the precipitation. This can occur if the wrong clutter suppression was used (A software used to eliminate false echoes from the screen). Or that there was high based thunderstorms over a dry air mass. The precipitation from high elevation clouds that would evaporated before it had fallen low enough in elevation for the radar beam can pick it up. The best clue to this reason was did you see any precipitation with these thunderstorms? The base of the thunder cloud I have seen out west can be well above 12,000 feet high and may not be detected by radar. As stated by others, this is called dry lightning and usually occurs early into the thunderstorm event as it will take some time for the rain to finally moisten up the low levels of the air mass. Once that happens, rain will finally reach the surface or at least low enough to be finally detected by radar.

There was also a chance that the radar picture was old and was not updating. If this happens again, check if the local NWS office had issued any short term forecast statements about the storms.

Answer 2

It depends on how far you are away from radar that you were looking at and what's between you and the radar beam. If you live in a mountainous area then the radar can have real problems. I don't know what website you were looking at for the radar, but some sites let you look at different tilt angles--the radar sweeps around in a circle and then changes its tilt with each turn, so the higher angles will often see storms that are blocked by terrain at low levels. Another possibility is that it was a dying storm that didn't have a lot of rain but was still electrified.

Some of the answers are wrong. Heat lightning is just regular lightning that is too far away to hear the thunder, and while some storms don't produce much rain, those that produce lightning have enough rain or hail to be seen on radar (at least early in the storm).

Answer 3

the doppler radar system is a great system, but it does have its downfalls. the comment of doppler showing precipitation is only partially accurate, it also shows winds and whether or not they are moving toward or away from the radar site.

the doppler radar's big down fall is how it scans.

it scans the skies in layers, and is unable to follow the curve of the earth's surface so it doesnt see stuff that is closer to the ground at far distances. and it can not see what is directly above it. thus there are many areas that have no radar coverage.
and remember, all radar images (especially NWS radar images) are usually delayed 10-15 minutes due to the multiple layer scan that the doppler uses. it has to make 2-3 sweeps changing angles each time to get an image, then it must merge the layers together to get the display image shown on a computer or TV.

Answer 4

Dry cells. In dry air, you can get this. The radar will only show rain. An example of this is during the summer, there is aircraft delays in Denver but no rain "weather" on the state radar. And or it might be raining aloft (20'000 ft) but the rain will not hit the ground. Again air is too dry. Southern CA has this problem during there fire seasons.

Also Ive seen lightning 200 miles away at night.

Answer 5

You experienced what is called a dry thunderstorm. The precipitation they produce doesn't reach the ground because of how dry it is. However, there's so much instability and dynamics aloft that the thunderstorms developed and with the heat in place, produced plenty of lightning.

Answer 6

Doppler radar's don't show lightning and thunder. All they show is precipitation.

Answer 7

could have been heat lightning. normal lightning is made by water molecules in clouds rubbing up against each other, transferring charge. heat lightning is just air molecules at a very high altitude.