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How to look for sprites


Whenever thunderstorms are around, it is possible, with a little luck, to spot a “transient luminous event” above the storm. Sometimes you might not even be looking intentionally, and it just happens. Below we summarize the basics of what to look for and how to interpret what you may have have seen.

Your reports are valuable. If you can provide enough detail, it can help researchers better understand the types of storms that produce these phenomena. And we are really, really interested in reports of upward discharges from thunderstorm tops such as blue jets and upward lightning. Also, “ball lightning” is a subject that is again gaining interest from the atmospheric electricty community. If you believe you have seen such a phenomenon, please let us know and we will forward your report to the appropriate researchers.

If you have obtained still images or video, then your observations would be especially valuable to helping advancing scientific study of these events

If you have an observation you wish to contribute to the growing base of reports from amatuers and professionals alike, click here.

General Rules: Most optical transients above thunderstorms are fairly dim (with the exception of upward lightning.)
So, once you have checked out the satellite and radar maps to locate storms within range of your location, the following will help improve your chances:

Moonless nights are preferred.
Rural locations far from urban light pollution are optimal.
Select nights with a minimum of haze, smoke or pollution in the atmosphere.
It is best to let your eyes become dark-adapted for five or ten minutes.
If the lightning from the storm system is visible, it may be best to block out their glare to enhance chances of seeing the dimmer features above.
Sometimes you have better luck by looking off to the side of the storm as you can see dimly illuminated objects better out of the corner of your eye.
Have a watch set to the second to obtain an accurate time for any event.
Listen to an AM radio (tuned to an unused frequency near the low end of the band). Sprites may coincide with unusual or strong bursts of static (called “sferics”)
Bring a chair, and perhaps something to support your head, while watching.
If you have a “night scope,” which are becoming increasingly inexpensive, use it. Many sprites show up very clearly even on older surplus units.

Appearance: curtains or streaks, rather like an aurora.
Color: salmon red, but sometimes people see them as white or green.
Duration: really fast! Literally about the blink of eye.
Frequency: in active storms, every one or two minutes possible; 5 mintutes more common. Most storms “sprite” for several hours once they start.
Relation to lightning: appears simultaenous with bright flash in cloud if storm not too far away.
Type of thunderstorms: very large thunderstorm system and complex squall lines.
Size of thunderstorm: the storm should be at least the size of the state of Connecticut.
Portion of thunderstorm: above the weaker radar echeos, often trailing behind the intense leading edge.
Look well above the storm top (2 to 4 times the height of the storm.)
When in life cycle: mature and late mature stages of storm.
Range to storm: best for storm to be 100 to 300 miles away.
Best part of country: anywhere east of Rockies in summer, especially the Central and Northern Plains.
Best time: whenever dark, but 10 PM to midnight seems to be the best bet.
AM radio static: sprite will often be coincident with loudest radio static.
Photography: set video camera on widest aperture and let run - brightest may be faintly vsible. Sprites probably not detectable
on still imagers.

Appearance: a cone-shaped, upward moving fountain of light, often brighter on top. May be at angle to vertical.
Color: dim blue.
Duration: about a quarter of a second; just slow enough to sense upward motion.
Frequency: sometimes a singular event; others every minute or so for an hour or more.
Relation to lightning: usually above electrically active part of stom but unrelated to specifc flashes.
Type of thunderstorms: more intense storms, possibly related to tornadoes and hail (supercells.)
Size of thunderstorm: generally smaller storms (supercells), or individual cells in squall lines.
Portion of thunderstorm: near the highest portion of cloud, perhaps near overshooting dome.
When in life cycle: probably in growth and early mature phase.
Range to storm: best within 100 miles (blue light does not transmit well though the atmosphere.)
Best part of country: Central US, but maybe storms over ocean and Gulf Stream as well.
Best time: at night, in order to see dim blue light.
AM radio static: not related to specific static, but storm likely to be very active.
Photography: set video camera on widest aperture and let run; set for time exposures on still cameras; use a tripod.

Appearance: similar to a conventional lightning bolt, generally rather straight, may be tilted off vertical axis;does not flicker like cloud-to-ground flashes.
Color: yellow or white lightning channel, maybe with blue flames above.
Duration: unusually long? Some reports of one, two and even 5 seconds duration.
Frequency: seems to occur every several minutes, sometimes for 40 minutes or more.
Relation to lightning: unknown; storms may have very high to almost zero lightning rates.
Type of thunderstorms: supercells, tornadic storms; rapidly growing cells with cauliflower tops.
Size of thunderstorm: smaller (10s of miles across), especially those associated with severe weather.
Portion of thunderstorm: above the highest part of thunderstom - may see cauliflower dome protuding into stratosphere
When in life cycle: most likely when storm is young and in maximum growth stage.
Range to storm: nearby storms best, perhaps visible to 100-200 miles away.
Best part of country: Central US and very possibly along Gulf and Atlantic coastal areas.
Best time: anytime? brilliant enough to be visible both day and night.
AM radio static: storm may have active static, but may not be required.
Photography: set video camera on widest aperture and let run; set for time exposures on still cameras; use a tripod.

So-called “heat lightning” can sometimes be mistaken for sprites or even blue jets. Heat lightning is nothing more than the reflection of regular lightning occurring within distant thunderstorms largely below the horizon. Its color can range from white to blue and even reddish. It can be fan shaped. A rate of several flashes per minute or more may be a tip off.

Ball lightning is extremely rare - so rare that some scientists don’t really believe it exists. It often follows a nearby lightning strike. The glowing plasma can drift or dart around, lasts for seconds to minutes, comes in a variety of colors, often can appear to go through walls, sometimes makes hissing noises…and is completely weird. If you have an encounter with ball lightning, we’d love to hear from you. If you get a picture…you’ll be famous!

Recent reports have suggested unusual electrical effects near thunderstorms, especially tornadic supercells. These events appear as fast moving streaks of light, often with a bright leading glow. Several still and video images have been obtained in recent years, but it is not clear whether they may not be an artifact of newer types of CCD imaging systems now in widespread use. If you see and/or photograph such a strange shooting streak of light below the base of the cloud, we would really like to hear about it.

If you see a nice aurora, the folks at www. SpaceWeather.com would like to hear from you.

And if you see something that just doesn’t fit anything we discussed on this web site, do your best to describe it and let us know.

But…we don’t do UFOs, little green men, mystical events, ghosts or the supernatural here. We just do scientific observations of atmospheric electricity and related phenomena.


Satellite: This is an infrared (heat) image of the clouds over the U.S. The higher the cloud top, the colder it is. The coldest clouds in this display are the darkest blue. Reddish areas usually represent clear skies.