<p><strong>Why are cumulus the only basic cloud type to favor lightning?</strong><br>
Because the speed of rising in the updraft is fundamental to lightning formation, as shown by this example plot from <a href="http://www.goes-r.gov/resources/Scipubs/docs/2008/2007JD009598.pdf" rel="nofollow noreferrer">Total lightning activity as an indicator of updraft characteristics by Deierling and Petersen</a>:</p>

<p><a href="https://i.sstatic.net/FMEqQ.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/FMEqQ.png" alt="updraftvslightning"></a></p>

<p>The faster the air rises, the more lightning in makes.  Only rapid updrafts can separate charges fast enough to overcome dissipation and build up the <a href="http://hyperphysics.phy-astr.gsu.edu/hbase/electric/lightning2.html" rel="nofollow noreferrer">hundreds of millions of Volts</a> (related <a href="https://electronics.stackexchange.com/questions/10909/lightning-bolt-vs-batteries-a-coulomb-in-everyday-terms">ESE question</a>) needed for lightning.  Out of the three standard cloud categories, only cumulus involves significant vertical motion.</p>

<hr>

<p><strong>Other cloud types?</strong><br>
First off, <strong>nearby clouds of other types can mask the cumulus structure responsible for the lightning</strong>.  Very commonly in strong storm environments, the broad widespread rising motion, especially near the warm front, can cause a thick low-level stratus deck to form.  And sometimes, in situations where dynamic forcing is dominant (such as with upper-level storm systems), or where storms move into a new environments (such as lake effect snow storms), fog can be thick, such that basically nothing can be seen!  So in those situations, its hard to truly attribute the lightning to the cumulonimbus, despite that being the cause.</p>

<p>Plus, full storm cells often develop fairly complex structures:</p>

<p><a href="https://i.sstatic.net/Lbjtd.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/Lbjtd.png" alt="supercell"></a>(Wikipedia, credit Kelvinsong)</p>

<p>Due to their shape and motions, <strong>some parts of storms might reasonably be categorized as stratus or altostratus, though they stem from a larger (past or present) cumulonimbus structure</strong>. These stratus-like components include <a href="https://en.wikipedia.org/wiki/Arcus_cloud" rel="nofollow noreferrer">arcus</a>, <a href="https://en.wikipedia.org/wiki/Cumulonimbus_incus" rel="nofollow noreferrer">incus</a>, and <a href="https://en.wikipedia.org/wiki/Cumulonimbus_velum" rel="nofollow noreferrer">velum</a>.  And <a href="http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/cld/cldtyp/oth/mm.rxml" rel="nofollow noreferrer">mammatus clouds</a> that can occur as part of strong storms are actually a unique example of clouds with sinking air.  Even though air in these regions isn't rising much, leftover charge from nearby (or past) updrafts can still bring about lightning.  <a href="https://www.google.com/search?q=youtube%20anvil%20crawlers&amp;ie=utf-8&amp;oe=utf-8#tbm=vid&amp;q=anvil%20crawlers&amp;*" rel="nofollow noreferrer">Anvil crawlers</a> are a common lightning seen in the fairly flat upper regions of storms.  </p>

<p>Also, while more precise cloud classifications do now set the stages of growing thunderstorms clouds into the cumulonimbus genus, the nimbus prefix <a href="http://www.etymonline.com/index.php?term=nimbus&amp;allowed_in_frame=0" rel="nofollow noreferrer">classically meant precipitating</a> (raining/hailing/snowing).  <strong>Precipitation reaching the ground is not an absolute requirement for a storm cloud to produce lightning</strong>.  So in a loose sense, a cloud doesn't truly have to be a cumulo<em>nimbus</em>, at least historically.</p>

<p>And of course, as it can do with just about any non-insulating material, <strong>lightning can pass through inactive clouds</strong> on the journey to the ground.</p>

<p><strong>But while these situations may technically satisfy your search for lightning in other clouds types, you're fundamentally right, standard lightning generally derives from cumuloform cloud origins.</strong></p>

CC BY-SA 3.0
2017-04-04T11:45:53.287Z
This writeup doesn't include mention of more exotic forms of lightning, like sprites and such, because I'm just not familiar enough with those topics.  Since I believe some types pass upward into the stratosphere, or even occur in cloudless environments in higher atmospheric layers, these might well be options for non-cumulonimbus forms as well.
JeopardyTempest
CC BY-SA 3.0
2017-04-04T22:01:13.077Z
@gansub: I'd really defer to direct researchers on the nuances of topic for any answer with more sweeping confidence.
JeopardyTempest
CC BY-SA 3.0
2017-04-04T22:03:44.353Z
I find cloud classification a little quixotic (some references suggest that anything with lightning is automatically coined cumulonimbus) [This book](https://books.google.com/books?id=8lpzAwAAQBAJ&pg=RA1-PA197&lpg=RA1-PA197&dq=typical+updraft+speeds+stratus&source=bl&ots=ZFSJ6ifCSA&sig=uuwLrmUQl-lhp-LhCEf1zI54_UE&hl=en&sa=X&ved=0ahUKEwiT3LKh4ovTAhVMRSYKHSMNDFQQ6AEIIjAB#v=onepage&q=typical%20updraft%20speeds%20stratus&f=false) suggests updraft speeds of 0.1-1 m/s, possible in stratocu, so placing that in the plot might suggest at least a rare lightning strike is possible.
JeopardyTempest
CC BY-SA 3.0
2017-04-04T22:13:13.197Z
Perhaps it'd be more favored in some areas, such as those with larger sustained uplift, as near orography.  But for what it's worth, I haven't had any experience of such lightning in my little world.  And would tend to think that the different dynamics -- the smaller depth of the updraft -- just wouldn't support lightning from stratiform clouds.
JeopardyTempest
CC BY-SA 3.0
2017-04-05T05:21:23.027Z
Almost ended up on a lightning research project in grad school, but it would've been more directed at attempting to predict it based upon environment, than any detailed direct observations.  Ended up working on idealized hurricanes in shear instead.  Interesting, albeit challenging, stuff.  The moniker came about when I was but a young gradeschool student attempting to come up with something unique in the earlier internet era (mid 90s).  Seen plenty of lightning in my years here in Orlando, and also around Oklahoma when I was there... but indeed it's still yet an incomplete experience set!
JeopardyTempest
CC BY-SA 3.0
2017-04-04T11:42:22.737Z
2017-04-04T22:14:32.690Z
2017-04-13T12:33:09.780Z
JeopardyTempest
<p>There are several number of cloud types, but I only know that cumulonimbus clouds discharge electricity, which in turn produces thunder and lightning. Is this type of cloud (cumulonimbus) the only cloud that can produce an electrical discharge or are there other clouds that can produce an electrical discharge?</p>

<meteorology><clouds>
Which clouds can produce lighting and thunder?
bashir ali
# Which clouds can produce lighting and thunder?

(Asked by: username_0 on 2017-04-02)

There are several number of cloud types, but I only know that cumulonimbus clouds discharge electricity, which in turn produces thunder and lightning. Is this type of cloud (cumulonimbus) the only cloud that can produce an electrical discharge or are there other clouds that can produce an electrical discharge?

**Tags:** meteorology, clouds


---

## 1 answers

### Answer by username_1 on 2017-04-04. Score: 4 | Accepted answer

**Why are cumulus the only basic cloud type to favor lightning?**  
Because the speed of rising in the updraft is fundamental to lightning formation, as shown by this example plot from [Total lightning activity as an indicator of updraft characteristics by Deierling and Petersen](http://www.goes-r.gov/resources/Scipubs/docs/2008/2007JD009598.pdf):

[![updraftvslightning](https://i.sstatic.net/FMEqQ.png)](https://i.sstatic.net/FMEqQ.png)

The faster the air rises, the more lightning in makes. Only rapid updrafts can separate charges fast enough to overcome dissipation and build up the [hundreds of millions of Volts](http://hyperphysics.phy-astr.gsu.edu/hbase/electric/lightning2.html) (related [ESE question](https://electronics.stackexchange.com/questions/10909/lightning-bolt-vs-batteries-a-coulomb-in-everyday-terms)) needed for lightning. Out of the three standard cloud categories, only cumulus involves significant vertical motion.

---

**Other cloud types?**  
First off, **nearby clouds of other types can mask the cumulus structure responsible for the lightning**. Very commonly in strong storm environments, the broad widespread rising motion, especially near the warm front, can cause a thick low-level stratus deck to form. And sometimes, in situations where dynamic forcing is dominant (such as with upper-level storm systems), or where storms move into a new environments (such as lake effect snow storms), fog can be thick, such that basically nothing can be seen! So in those situations, its hard to truly attribute the lightning to the cumulonimbus, despite that being the cause.

Plus, full storm cells often develop fairly complex structures:

[![supercell](https://i.sstatic.net/Lbjtd.png)](https://i.sstatic.net/Lbjtd.png)(Wikipedia, credit Kelvinsong)

Due to their shape and motions, **some parts of storms might reasonably be categorized as stratus or altostratus, though they stem from a larger (past or present) cumulonimbus structure**. These stratus-like components include [arcus](https://en.wikipedia.org/wiki/Arcus_cloud), [incus](https://en.wikipedia.org/wiki/Cumulonimbus_incus), and [velum](https://en.wikipedia.org/wiki/Cumulonimbus_velum). And [mammatus clouds](http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/cld/cldtyp/oth/mm.rxml) that can occur as part of strong storms are actually a unique example of clouds with sinking air. Even though air in these regions isn't rising much, leftover charge from nearby (or past) updrafts can still bring about lightning. [Anvil crawlers](https://www.google.com/search?q=youtube%20anvil%20crawlers&ie=utf-8&oe=utf-8#tbm=vid&q=anvil%20crawlers&*) are a common lightning seen in the fairly flat upper regions of storms.

Also, while more precise cloud classifications do now set the stages of growing thunderstorms clouds into the cumulonimbus genus, the nimbus prefix [classically meant precipitating](http://www.etymonline.com/index.php?term=nimbus&allowed_in_frame=0) (raining/hailing/snowing). **Precipitation reaching the ground is not an absolute requirement for a storm cloud to produce lightning**. So in a loose sense, a cloud doesn't truly have to be a cumulo*nimbus*, at least historically.

And of course, as it can do with just about any non-insulating material, **lightning can pass through inactive clouds** on the journey to the ground.

**But while these situations may technically satisfy your search for lightning in other clouds types, you're fundamentally right, standard lightning generally derives from cumuloform cloud origins.**

> **Comments:**
> **username_1**: This writeup doesn't include mention of more exotic forms of lightning, like sprites and such, because I'm just not familiar enough with those topics.  Since I believe some types pass upward into the stratosphere, or even occur in cloudless environments in higher atmospheric layers, these might well be options for non-cumulonimbus forms as well.  
> **username_1**: @gansub: I'd really defer to direct researchers on the nuances of topic for any answer with more sweeping confidence.  
> **username_1**: I find cloud classification a little quixotic (some references suggest that anything with lightning is automatically coined cumulonimbus) [This book](https://books.google.com/books?id=8lpzAwAAQBAJ&pg=RA1-PA197&lpg=RA1-PA197&dq=typical+updraft+speeds+stratus&source=bl&ots=ZFSJ6ifCSA&sig=uuwLrmUQl-lhp-LhCEf1zI54_UE&hl=en&sa=X&ved=0ahUKEwiT3LKh4ovTAhVMRSYKHSMNDFQQ6AEIIjAB#v=onepage&q=typical%20updraft%20speeds%20stratus&f=false) suggests updraft speeds of 0.1-1 m/s, possible in stratocu, so placing that in the plot might suggest at least a rare lightning strike is possible.  
> **username_1**: Perhaps it'd be more favored in some areas, such as those with larger sustained uplift, as near orography.  But for what it's worth, I haven't had any experience of such lightning in my little world.  And would tend to think that the different dynamics -- the smaller depth of the updraft -- just wouldn't support lightning from stratiform clouds.  
> **username_1**: Almost ended up on a lightning research project in grad school, but it would've been more directed at attempting to predict it based upon environment, than any detailed direct observations.  Ended up working on idealized hurricanes in shear instead.  Interesting, albeit challenging, stuff.  The moniker came about when I was but a young gradeschool student attempting to come up with something unique in the earlier internet era (mid 90s).  Seen plenty of lightning in my years here in Orlando, and also around Oklahoma when I was there... but indeed it's still yet an incomplete experience set!  

---

