Editing Cloud (section)

====Towering vertical====
[[File:Towering Verticle Thunderhead.jpg|thumb|Isolated cumulonimbus calvus cloud over the [[Mojave Desert]], releasing a heavy shower]]
[[File:Cumulonimbus-incus mykonos.jpg|thumb|Single-cell Cumulonimbus capillatus incus]]
These very large cumuliform and cumulonimbiform types have cloud bases in the same low- to mid-level range as the multi-level and moderate vertical types, but the tops nearly always extend into the high levels.  Unlike less vertically developed clouds, they are required to be identified by their standard names or abbreviations in all aviation observations (METARS) and forecasts (TAFS) to warn pilots of possible severe weather and turbulence.<ref name="automated Cb and Tcu detection"/>

* Species [[cumulus congestus]] – Increasing airmass instability can cause free-convective cumulus to grow very tall to the extent that the vertical height from base to top is greater than the base-width of the cloud. The cloud base takes on a darker gray coloration and the top commonly resembles a cauliflower. This cloud type can produce moderate to heavy showers<ref name="cumulus" /> and is designated ''Towering cumulus'' (Tcu) by the [[International Civil Aviation Organization]] (ICAO).
* Genus [[cumulonimbus]] (Cb) – This genus type is a heavy, towering, cumulonimbiform mass of free-convective cloud with a dark-gray to nearly black base and a very high top in the form of a mountain or huge tower.<ref name="cumulonimbus">{{Cite web |year=2017 |editor-last=World Meteorological Organization |title=Cumulonimbus, International Cloud Atlas |url=https://cloudatlas.wmo.int/clouds-genera-cumulonimbus.html |access-date=16 May 2017}}</ref> Cumulonimbus can produce [[thunderstorm]]s, local very heavy downpours of [[rain]] that may cause [[flash flood]]s, and a variety of types of [[lightning]] including cloud-to-ground that can cause [[wildfire]]s.<ref name="Scott2000">{{Cite journal |last=Scott A |year=2000 |title=The Pre-Quaternary history of fire |journal=Palaeogeogr Palaeoclimatol Palaeoecol |volume=164 |issue=1–4 |pages=281–329 |bibcode=2000PPP...164..281S |doi=10.1016/S0031-0182(00)00192-9}}</ref> Other convective severe weather may or may not be associated with thunderstorms and include heavy [[snow]] showers, [[hail]],<ref name="ncar">{{Cite web |last=National Center for Atmospheric Research |year=2008 |title=Hail |url=http://www.ncar.ucar.edu/research/meteorology/storms/hail.php |url-status=dead |archive-url=https://web.archive.org/web/20100527170048/http://www.ncar.ucar.edu/research/meteorology/storms/hail.php |archive-date=27 May 2010 |access-date=18 July 2009 |publisher=University Corporation for Atmospheric Research}}</ref> strong [[wind shear]], [[downburst]]s,<ref>[[Ted Fujita|Fujita, Ted]] (1985). "The Downburst, microburst and macroburst". SMRP Research Paper 210.</ref> and [[tornado]]es.<ref name="Renno">{{Cite journal |last=Renno |first=N. O. |year=2008 |title=A thermodynamically general theory for convective vortices |url=https://deepblue.lib.umich.edu/bitstream/2027.42/73164/1/j.1600-0870.2008.00331.x.pdf |archive-url=https://web.archive.org/web/20190502122954/https://deepblue.lib.umich.edu/bitstream/2027.42/73164/1/j.1600-0870.2008.00331.x.pdf |archive-date=2 May 2019 |url-status=live |journal=Tellus A |volume=60 |issue=4 |pages=688–699 |bibcode=2008TellA..60..688R |doi=10.1111/j.1600-0870.2008.00331.x |hdl-access=free |hdl=2027.42/73164}}</ref> Of all these possible cumulonimbus-related events, lightning is the only one of these that requires a thunderstorm to be taking place since it is the lightning that creates the thunder. Cumulonimbus clouds can form in unstable airmass conditions, but tend to be more concentrated and intense when they are associated with unstable [[cold front]]s.<ref name="G&N:207-212" />