learing the AviationWeather Formats: METAR/TAF
With a little practice and the help of the tear-out "decoder" card included in this booklet,
pilots will find it is easy to understand METARS (Aviation Routine Weather Reports)
and the airport terminal forecast referred to as TAF (aerodrome Forecast).
Those who use DUATs (Direct User Access Terminal) or commercially provided weather services will find all providers have included a plain language interpreter.
Let's check out a METAR
METAR (or SPECI for Special Report) KPIT 201955Z (AUTO for automated observation)
(COR for correction to observation)
22015G25KT 3/4SM R28R/2600FT TSRA OVC010CB 18/16 A2992 RMK SLPO13 T01760158
Note: When METAR data is missing from the body of the report (e.g. dew point),
it is simply omitted and the user must know the sequence to recognize this.
Some exceptions apply in remarks such as RVRNO, or SLPNO
when RVR or SLP are normally reported but not currently available.
To help remember the sequence, think of 3W's at the beginning-Where, When, and Wind
This works for METAR as well as TAF!
METAR KPIT 201955Z 22015G25KT
KPIT is the ICAO station identifier. The usual 3 letter identifiers we are all familiar with are now
receded by a "K" for the contiguous United States.
Alaska and Hawaii will use 4 letter identifiers beginning with "PA" and "PH" respectively.
201955Z is the 20th day of the month.
201955Z at 1955Z time
22015G25KT is reported as the 3 digit true direction to the nearest 10 degrees.
(Note: ATC towers, ATIS and airport advisory service report wind as magnetic.)
22015G25KT next is the 2 or 3 digit speed.
22015G25KT a "G" comes next if the wind is gusting.
22015G25KT followed by the 2 or 3 digit maximum speed and units (KT).
00000KT for calm winds.
22015KT 180V260 When wind direction varies 60 degrees or more and wind is greater than 6
VRB Used when wind direction is variable and speed is less than or equal to 6 knots.
RMK Peak wind is one element reported in the remarks section whenever the maximum instantaneous speed is greater than 25 knots.
22030/15 means a maximum instantaneous wind of 30 knots occurred 15 minutes past the hour from 220 degrees.
PK WND 22030/15
3/4SM meaning 3/4 statue mile visibility.
Miles and fractions are also reported (e.g., 3/4SM for 2 and 3/4 statute miles visibility).
R28R/2600FT Means Runway Visual Range (RVR).
Signifies that the runway visual range for runway 28 Right is 2600 feet.
The format is R(XXX)
Runway Designator including (L)eft(C)enter or (R)ight /(XXXX) 4 digit visibility in feet.
Some coding pilots may also see for RVR include:
M Indicates that RVR is less than lowest reportable sensor value (e.g. M0600FT)
P Indicates RVR greater than highest reportable sensor value (e.g. P6000FT).
V Variable If the RVR is variable between 2000 and 4000 feet for runway 6L:
(R06L/2000V4000FT). May contain up to four RVR reports.
SIGNIFICANT PRESENT WEATHER
TSRA: Thunderstorm/Moderate Rain
Format is a two character descriptor (e.g. TS, SH, DR)
sometimes followed by a two character weather phenomenon (e.g. RA, SN, FG).
(See Abbreviations Section). Intensity or proximity of weather phenomenon:
- - Light
+ - Heavy
no sign - Moderate
VC - In the vicinity
OVC010CB: Specifies cloud amount, height, and type.
Overcast clouds are present at 1000 feet consisting of umulonimbus clouds. Cloud height is reported in hundreds of feet.
When clouds are composed of towering cumulus or cumulonimbus TCU or CB will follow cloud height.
The clouds are categorized based on eighths (octas) of the sky:
SKC - Sky Clear
FEW - 1-2 octas
SCT - 3-4 octas
BKN - 5-7 octas
OVC - 8 octas
VV may be listed here for indefinite ceiling such as "VV004"
for Vertical Visibility 400 feet.
18/16: Temperature/Dew Point listed in degrees Celsius.
When temperatures are below zero degrees Celsius, they are preceded by "M" for Minus
(e.g., 10/M06 for temperature 10 degrees C, dew point Minus 6 degrees C).
A2992 Altimeter Setting "A" indicates setting in inches of mercury for United States.
Consists of 4 digits: inches and hundredths.
RMK SLP013 T01760158
RMK SLP013 T01760158. Remarks come last.
RMKSLP013 T01760158. Selected stations will contain SLP for Sea Level Pressure
reported as the last three digits n hectoPascals (milibars) to the nearest tenth
(e.g., 1001.3 is reported as SLP013).
RMK SLP013 T01760158. Also, at selected stations, the 9 character code (T01760158)
breaks down the temperature and dew point to the nearest 1/10th of a degree Celsius.
The "T" stands for temperature and the "0" means positive temperature.
A "1" in place of the "0" stands for negative temperature.
At selected stations, other temperature codes, such as 0142,
20012, or 401120084, may appear to document temperatures not related to aviation. NOT FINISCHED