常见航空气象符号总结

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Plotted Station (surface analysis)

Example

Overcast, with an air temperature of 24 degrees Celsius, dew point of 21 degrees Celsius. The wind was from the north-east between 10 and 14 knots. The pressure was 1003.8 millibars decreasing () of 1.1 millibars in the last 3 hours (1 1 on the chart). Rain showers with low clouds which were Stratus, the visibility was reduced to less than one kilometre. In the preceding hour of the observation, fog was the weather.

Plotted Station (upper air analysis)

	hh	Height of pressure level in decametres
h2h2	Thickness between two pressure levels (decametres). ex. 500 -1000 mb thickness
TT	Air Temperature (in degrees Celsius)
DD	Temperature - Dew Point Spread (in degrees Celsius)
ddd	Wind Direction (in tens of degrees)
ff	Wind speed (in knots)

Significant Weather Prog

	moderate turbulence
	severe turbulence
–	moderate to severe turbulence in Clear Air above 10000 feet
	moderate icing
	severe icing

	format used for convective cloud description
	few TCU / ACC embedded with tops at 18000 feet
	numerous TCU / ACC embedded with tops at 24000 feet

Cloud Cover in oktas Cloud Convective DescriptionTopBase	format used for cloud description
	6 oktas of cloud in layers with base lower than 10000 feet (or 700 mb) and tops from 16000 to 20000 feet
	6 oktas of cloud in layers with base at 12000 feet and tops at 18000 feet
	8 oktas of Nimbostratus cloud type with base lower than 10000 feet and tops at 22000 feet

Types of Fronts

	cold front
	warm front
	stationnary front
	occluded front
	Trough of warm air aloft (TROWAL)

Examples of Symbols used to illustrate the weather (ww)

	rain		ice pellets
	drizzle		hail
	rain shower		haze
	freezing rain		mist
	snow		fog
	snow shower		fog, depositing rime
	heavy rain shower		thunderstorm
	squalls		thunderstorm, heavy, with rain and/or snow
	ice pellets (shower)		thunderstorm, heavy, with hail
	lightning

Winds

	less than 5 knots		30 to 34 knots
	5 to 9 knots		35 to 39 knots
	10 to 14 knots		40 to 44 knots
	15 to 19 knots		50 to 54 knots
	20 to 24 knots		70 to 74 knots
	25 to 29 knots		105 to 110 knots and so on

Cloud Cover

	in oktas (/ 8)	in tenths (/ 10)
	no clouds
	1 okta or less	1 tenth or less but with a presence of cloud
	2 oktas	2 or 3 tenths
	3 oktas	4 tenths
	4 oktas	5 tenths
	5 oktas	6 tenths
	6 oktas	7 or 8 tenths
	7 oktas or more but not 8	9 tenths or more but not 10
	completely overcast
	Sky completely obscured by a layer at the surface or by a phenomenon with a base not at the surface

High Clouds : type CH

	CI (cirrus) in the form of filaments, strands, or hooks, not progressively invading the sky
	dense Ci, in patches or entangled sheaves, which usually do not increase
	dense Ci, often in the form of an anvil, being the remains of the upper parts of Cb (cumulonimbus)
	Ci in the form of hooks or of filaments, or both, progressively invading the sky
	Ci and Cs (CirroStratus) or Cs alone; in either case, they are progressively invading the sky, and generally growing denser as a whole, but the continuous veil does not reach 45 degrees above the horizon
	Ci and Cs or Cs alone; in either case, they are progressively invading the sky, and generally growing denser as a whole; the continuous veil extends more than 45 degrees above the horizon
	veil of Cs covering the celestial dome
	Cs not progressively invading the sky and not completely covering the celestial dome, Ci and Cc (CirroCumulus) may be present
	Cc alone, or Cc accompanied by Ci or Cs, or both, but Cc is predominant

Middle Clouds : type CM

	As (AltoStratus), the greater part of which is semi-transparent; through this part the sun or moon may be weakly visible, as through ground glass.
	As, the greater part of which is sufficiently dense to hide the sun or moon, or Ns (NimboStratus)
	Ac (AltoCumulus), the greater part of which is semi-transparent; the various elements of the cloud change only slowly and are all at a single level mince
	patches (often in the form of almonds or fishes) of Ac, the greater part of which is semi-transparent; the clouds occur at one or more levels and the elements are continually changing in appearance
	semi-transparent Ac in bands, or Ac in one or more fairly continuous layers (semi-transparent or opaque), progressively invading the sky; these altocumulus clouds generally thicken as a whole
	Ac resulting from the spreading out of Cu (Cumulus)
	Ac in two or more layers, usually opaque in places, and not progressively invading the sky; or opaque layer of Ac, not progressively invading the sky; or Ac together with As
	Ac with sproutings in the form of small towers or battlements; or altocumulus having the appearance of cumuliform tufts
	Ac of a chaotic sky, generally at several levels

Low Clouds : type CL

	Cu (Cumulus) with little vertical extent and seemingly flattened
	Cu of moderate or strong vertical extent, generally with protuberances in the form of domes or towers, either accompanied or not by other cumulus or by stratocumulus, all having their base at the same level.
	Cb (CumuloNimbus) the summits of which, at least partially, lack sharp outlines but are neither clearly fibrous (cirriform) nor in the form of an anvil; cumulus, stratocumulus, or stratus may also be present
	Sc (StratoCumulus) formed by the spreading out of cumulus; cumulus may also be present
	Sc not resulting from the spreading out of cumulus
	St (Stratus) or Sf (Stratus Fractus) in a more or less continuous sheet or layer, or in ragged shreds, or both, but no stratus fractus of bad weather
	Sf (stratus Fractus) of bad weather or cumulus fractus of bad weather, or both (pannus), usually below altostratus or nimbostratus
	Cu and Sc other than that formed from the spreading out of cumulus; the base of the cumulus is at a different level from that of the stratocumulus
	Cb cumulonimbus, the upper part of which is clearly fibrous (cirriform), often in the form of an anvil; either accompanied or not by cumulonimbus without anvil or fibrous upper part, by cumulus, stratocumulus, stratus, or pannus

Horizontal Visibility Code vs Kilometers (VV)

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