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METAR Decoding Information
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METAR Decoding Information

METAR code is a standardized textual format for describing weather conditions at wx stations and airports.  To decode items, use the table below (applies to METAR and TAF items):

METAR
KPIT 091955Z COR 22015G25KT 3/4SM R28L/2600FT TSRA OVC010CB 18/16 A2992 RMK SLP045 T01820159

TAF
KPIT 091730Z 091818 15005KT 5SM HZ FEW020 WS010/31022KT FM1930 30015G25KT 3SM SHRA OVC015 TEMPO 2022 1/2SM +TSRA OVC008CB FM0100 27008KT 5SM SHRA BKN020 0VC040 PROB40 0407 1SM -RA BR FM1015 18005KT 6SM -SHRA OVC020 BECMG 1315 P6SM NSW SKC

Forecast

Explanation

Report

TAF

Message type:

TAF -routine or TAF AMD-amended forecast, METAR-hourly, SPECI-special or TESTM-non-commissioned ASOS report.

METAR

KPIT

ICAO location indicator

KPIT

091730Z

Issuance time:

ALL times in UTC "Z", 2-digit date, 4-digit time

091955Z

091818

Valid period:

2-digit date, 2-digit beginning, 2-digit ending times

In U.S. METAR:

CORrected ob; or AUTOmated ob for automated report with no human intervention; omitted when observer logs on

COR

15005KT

Wind:

3 digit true-north direction, nearest 10 degrees (or VaRiaBle);

next 2-3 digits for speed and unit, KT (KMH or MPS); as needed, Gust and maximum speed; 00000KT for calm;

for METAR, if direction varies 60 degrees or more, Variability appended, e.g. 180V260

22015G25KT

5SM

Prevailing visibility: in U.S., Statute Miles & fractions; above 6 miles in TAF Plus 6SM. (Or, 4-digit minimum visibility in meters and as required, lowest value with direction)

3/4SM

Runway Visual Range:

R; 2-digit runway designator Left, Center, or Right as needed; "/"; Minus or Plus in U.S, 4-digit value, FeeT in U.S. (usually meters elsewhere); 4-digit value Varialbility 4-digit value (and tendency Down, Up or No change)

R28L/2600FT

HZ

Significant present, forecast and recent weather: see table (below)

TSRA

FEW020

Cloud amount, height and type:

SKy Clear 0/8,
FEW>0/8-2/8,
SCaTtered 3/8-4/8,
BroKeN 5/8-7/8,
OVerCast 8/8;
3-digit height in hundreds of ft;

Towering CUmulus or CumulonimBus in METAR; in TAF, only CB. Vertical Visibility for obscured sky and height "VV004". More than 1 layer may be reported or forecast. In automated METAR reports only, CLeaR for "clear below 12,000 feet"

OVC010CB

Temperature:

degrees Celsius; first 2 digits, temperature "/" last 2 digits, dew-point temperature;

Minus for below zero, e.g., M06 18/16

Altimeter setting:

indicator and 4 digits; in U.S., A-inches and hundredths; (Q -hectoPascals, e.g. Q1013)

A2992

WS010/31022KT

In U.S. TAF, non-convective low-level (<=2,000 ft) Wind Shear; 3-digit height (hundreds of ft); "/" , 3-digit wind direction and 2-3 digit wind speed above the indicated height, and unit, KT

In METAR, ReMarK indicator & remarks. For example:
Sea-Level Pressure in hectoPascals & tenths, as shown: 1004.5 hPa;
Temp/dew-point in tenths °C, as shown: temp 18.2°C, dew-point 15.9°C
RMK
SLP045
T01820159
FM1930

FroM and 2-digit hour and 2-digit

minute beginning time: indicates significant change.

Each FM starts on a new line, indented 5 spaces.

TEMPO 2022 TEMPOrary: changes expected for < 1 hour and in total, < half of 2-digit hour beginning and 2-digit hour ending time period
PROB40 0407 PROBability and 2-digit percent (30 or 40): probable condition during 2-digit hour beginning and 2-digit hour ending time period
BECMG 1315 BECoMinG: change expected during 2-digit hour beginning and 2-digit hour ending time period
Table of Significant Present, Forecast and Recent Weather - Grouped in categories and used in the order listed below; or as needed in TAF, No Significant Weather.

QUALIFIER

Intensity or Proximity:

- Light "no sign" Moderate + Heavy
VC Vicinity: but not at aerodrome; in U.S. METAR, between 5 and 10SM of the point(s) of observation; in U.S. TAF, 5 to 10SM from center of runway complex (elsewhere within 8000m)

Descriptor: Precipitation:
MI Shallow
BC Patches
PR Partial
TS Thunderstorm
BL Blowing
SH Showers
DR Drifting
FZ Freezing
DZ Drizzle
RA Rain
SN Snow
SG Snow grains
IC Ice crystals
PL Ice pellets
GR Hail
GS Small hail/snow pellets
UP Unknown precipitation in automated observations
Obscuration: Other:
BR Mist(>= 5/8SM)
FG Fog(< 5/8SM)
FU Smoke
VA Volcanic Ash
SA Sand
HZ Haze
PY Spray
DU Widespread dust
SQ Squall
SS Sandstorm
DS Duststorm
PO Well developed
FC Funnel cloud
+FC tornado/waterspout dust/sand whirls