Cloud
species – classification by shape and form
|
Species |
abbreviation |
description |
Cloud types |
|
Humilis |
hum |
Flattened, base
wider than height |
Cu |
|
Mediocris |
med |
Width of base and
height approximately equal |
Cu |
|
Congestus |
con |
Height larger
than width, cauliflower tops |
Cu |
|
Fractus |
fra |
Ragged shreds of
clouds |
Cu, St |
|
Nebulosus |
neb |
Thins veil or
layer with no distinct features |
St, As, Cs |
|
Stratiformis |
str |
Very extensive
horizontal sheet or layer |
Sc, Ac, Cc |
|
Calvus |
cal |
Smooth tops,
loosing cauliflower appearance, no cirrus |
Cb |
|
Cappilatus |
cap |
Distinct icy
regions with fibrous, striated appearance (anvil, plume or disordered mass of
cirrus) |
Cb |
|
Floccus |
flo |
Small tufts of
cloud, with ragged lower portions, often virga |
Ac, Cc, Ci |
|
Castellatus |
cas |
Turrets connected
by a common base, sometimes arranged in lines |
Sc, Ac, Cc, Ci |
|
Lenticularis |
len |
Wave cloud,
almond or lense shaped |
Sc, Ac, Cc |
|
Fibratus |
fib |
Nearly straight,
or slightly curved, no hooks |
Ci, Cs |
|
Spissatus |
spi |
Dense enough to
appear grey toward the sun |
Ci |
|
Uncinus |
unc |
Comma- or hook
shaped, not rounded tuft of cloud |
Ci |
Cloud
varieties – classification by transparency or arrangement of elements
|
Variety |
Abbreviation |
Description |
Cloud types |
|
Intortus |
in |
Irregularly
curved, tangled |
Ci |
|
Vertebrates |
ve |
Looking like
ribs, fishbones |
Ci |
|
Undulatus |
un |
Patches or rolls
with parallel undulations, billows |
Sc, Ac, As, Cc, Cs |
|
Radiatus |
ra |
Broad parallel
bands, appearing to converge due to perspective |
Cu, Sc, Ac, As,
Ci |
|
Lacunosus |
la |
Thins cloud with
regularly spaced holes (rare) |
Ac, Cc |
|
Duplicatus |
du |
More than one
layer, at slightly different levels |
Sc, Ac, As, Ci,
Cs |
|
Translucidus |
tr |
Translucent
enough to show positions of sun or moon |
St, Sc, Ac, As |
|
Perlucidus |
pe |
Broad layers or
patches, with spaces (occasionally very small) that allow blue sky |
Sc, Ac |
|
Opacus |
op |
Completely masks
sun or moon |
St, Sc, Ac, As |
Accessory
clouds – always occur in association with a genus
|
Accessory
cloud |
Description |
Cloud type |
|
Pannus |
Shreds of
dark cloud beneath the main cloud |
Cu, Cb, As,
Ns |
|
Pileus |
Cap cloud,
smooth cloud appearing above Cu or Cs, short-lived |
Cu, Cb |
|
Velum |
Veil; dark
thin sheet of cloud accompanying cumuliform clouds; long-lived |
Cb |
Supplementary
cloud features – indicative of precip or cloud origin
|
Feature |
Description |
Cloud type |
|
Arcus |
Squall roll
preceding Cb, shelf cloud |
Cb |
|
Incus |
Anvil cloud,
mature thunderstorm |
Cb |
|
Mammatus |
Pouches
hanging from upper cloud, often anvil
clouds; occur when cold moist air is met by rising drier and warmer air |
Cb (Sc, Ac,
As, Ci, Cc) |
|
precipitatio |
Precipitation
reaching the ground, may appear as dark region beneath clouds |
Cb, Nb |
|
Virga |
Fall streaks
from precipitating clouds, which evaporate before reaching the ground |
Cb, Cu con,
St, Sc |
|
Tuba |
Funnel clouds
of any type |
Cb |
|
Contrails |
Lingering
remnants of aircraft exhaust and accompanying condensation |
|
Last
modified: 1/14/2008
Maintained
by Sylke Boyd