Reading and decoding METAR reports

How to Read a METAR Weather Report

KPIT 201955Z (COR for correction to observation) 22015G25KT 3/4SM R28R/2600FT TSRA OVC01OCB 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

WHERE

KPIT is the ICAO station identifier. The usual
3 letter identifiers we are all familiar with are now preceded by a “K” for the contiguous United States. Alaska and Hawaii will use 4 letter identifiers beginning with “PA” and “PH” respectively. Changes are planned to incorporate alphabetic identifiers for those weather reporting stations where numbers and letters are now used (e.g., W10 to KHEF).

WHEN

201955Z is the 20th day of the month.

201955Z at 1955Z time

WIND

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 knots.

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

VISIBILITY

3/4SM meaning 3/4 statue mile visibility. Miles and fractions are also reported (e.g., 2 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

“C” In the vicinity

CLOUDS

OVC010CB: Specifies cloud amount, height, and type. Overcast clouds are present at 1000 feet consisting of cumulonimbus clouds.

Cloud height is reported in hundreds of feet. When clouds are composed of towering cumulus or cumulonimbus TCU or CBwill 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.

RMK SLP013 T01760158. Selected stations will contain SLP for Sea Level Pressure reported as the last three digits in 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 as10142, 20012, or 401120084, may appear to document temperatures not related to aviation.

METAR ON ASOS/AWOS

ASOS/AWOS reports will also use METAR/SPECI code formats. An ASOS/AWOS report can be identified by the term A01 or A02 (see abbreviations in back cover) in the remarks (RMK) section. Example:

METAR KOFP 251955Z AUTO 30008KT 10SM CLR 22/10 A3010 RMK AO2 SLP138 T02180096

Some ASOS/AWOS sites are attended. When a site is attended, the term AUTO is not included in the report (A01 or A02 remain). An attended site may contain information that has been manually provided by the observer.

Only a fully automated site without human intervention will contain the word AUTO.

When ASOS/AWOS reported sky condition is clear (CLR) it means no clouds at or below 12,000 feet.

METAR (SPECI or Special Report)

Note: When METAR data is missing (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.

METAR KPIT 201955Z 22015G25KT 3/4SM R28R/2600FT TSRA OVC010CB 18/16 A2992 RMK SLP013 T01760158

Where: KPIT

When: 201955Z 20th day of month at 1955Z

Wind: 22015G25KT 220 degrees at 15 gusting to 25 knots

V: Variable direction e.g., 20015KT 220V280

VRB: Variable direction when speed is less than or equal to 6 knots

Visibility: 3/4SM 3/4 statute miles, typical: 2 3/4SM, 1SM,

RVR R28R/2600FT Runway 28 Right visibility 2600 feet

M: Used for RVR less than lowest reportable sensor value (e.g. M0600FT)

P: Used for RVR greater than highest reportable sensor value

(e.g. P6000FT)

V: Variable

Significant Weather: TSRA thunderstorm/moderate rain (See Abbreviations)

Sky Condition: OVC010CB overcast clouds at 1000 feet consisting of cumulonimbus

Typical: SKC, FEW, SCT, BKN, VV004 indefinite ceiling (Vertical Visibility) 400 feet

Temperature/Dew Point: 18/16 18 degrees Celsius/dew point 16 degrees Celsius

M = Minus (below zero)

Altimeter: A2992 inches of mercury and preceded by an “A”

RMK SLP013 T01760158 10142 20012 401120084 At selected stations, Sea Level Pressure is reported as the last three digits in hectoPascals (milibars) (e.g., 1001.3 is reported as SLP013). Codes such as T01760158 10142 20012 and 401120084 are climate temperature information.

TAF (TAF AMD is Amended Forecast when included)

KPIT 091730Z 091818 22020KT 3SM -SHRA BKN020 WS015/30045KT

FM2030 30015G25KT 3SM SHRA OVC015 TEMPO 2022 1/2 TSRA OVC008CB

FM2300 27008KT 5SM -SHRA BKN020 OVC040 PROB40 0407 00000KT 1SM -RA BR

FM1000 22010KT 5SM -SHRA OVC020 BECMG 1315 20010KT P6SM NSW SKC

Where: KPIT

When: 091730Z issuance day and time: 9th day at 1720Z

091818 valid period: 9th day at 1800Z to next day (10th) at 1800Z

Wind: 22020KT 220 degrees at 20 knots

Visibility: 3SM 3 statute miles, typical – 2 3/4SM, 1SM,

P6SM: Greater than 6 statute miles

Significant WX: – SHRA light rain showers (See Abbreviations)

Sky Condition: BKN020 broken clouds at 2000 feet.

Typical: FEW, SCT, BKN, OVC.

VV004 indefinite ceiling (Vertical Visibility) 400 feet. CB and TCU clouds noted when present.

Wind Shear: WS015/30045KT low level wind shear at 1500 feet forecast to be 300 degrees at 45 knots (only nonconvective, low level, wind shear is forecast)

Sequence of Wind, Visibility, Significant Weather and Sky Condition repeats preceded by:

FM2030: From 2030Z

TEMPO 2022: Temporarily between 2000Z and 2200Z.

FM2300: From 2300Z

PROB40 0407: There is a 40 percent probability between 0400Z and 0700Z

FM1000: From 1000Z

BECMG 1315: Becoming between 1300Z and 1500Z

Note: Weather conditions such as wind and sky condition may be omitted after

PROB40, TEMPO, and BECMG if no change is expected from those same conditions given in the previous time block.