Section 4. Weather Phraseology

2-4-1. SURFACE OBSERVATIONS

Use the following phraseology and procedures for stating surface weather observations and for information similarly encoded in other aviation weather products and forecasts.

  1. Location.
    1. Announce the geographic name (not the identifier) once.
    2. When the location name is duplicated within 500 miles, follow the location name with the state name.
    3. When weather reports originate at more than one airport at the same geographical location, identify the airport.
    4. Where it is considered necessary or is requested by the military base commander, broadcast military observations by stating the location, the name of the airport if different, and the controlling military branch.
  2. Special and automated weather reports.
    1. If a special report is the most recent observation available, follow the location with the words “SPECIAL WEATHER REPORT,” (last two digits of the time) “OBSERVATION.”
    2. If “AUTO” appears after the date/time element and is presented as a singular report, follow the location with the word “AUTOMATED.”
    3. If the current report is both a special report and automated, follow the location with the words “SPECIAL WEATHER REPORT, (last two digits of the time) OBSERVATION AUTOMATED.”
  3. Missing weather data. If the weather data is not available, state the location and the word “MISSING.”
  4. Wind direction and speed.
    1. Announce surface wind direction and speed by stating the word “WIND” followed by the separate digits of the wind direction to the nearest 10 degrees and the separate digits of the speed.
    2. A “G” between two wind speed values is announced as “GUSTS.”
    3. A “V” between two wind direction values is announced as “VARIABLE.”
    4. When indicated, preface the values with the words “VARIABLE BETWEEN,” followed by the first value, the word “AND,” and then the second value.
    5. Announce the variability of wind at the end of the wind group.

      EXAMPLE-

      Wind

      Phraseology

      00000KT

      WIND CALM

      26012KT

      WIND TWO SIX ZERO AT ONE TWO

      29012KT 260V320

      WIND TWO NINER ZERO AT ONE TWO, VARIABLE BETWEEN TWO SIX ZERO AND THREE TWO ZERO

      30008KT

      WIND THREE ZERO ZERO AT EIGHT

      36012G20KT

      WIND THREE SIX ZERO AT ONE TWO, GUSTS TWO ZERO

      VRB04KT

      WIND VARIABLE AT FOUR

  5. Visibility. State the word “VISIBILITY” followed by the visibility values in miles and/or fractions of miles, except announce values indicated by the figure “0” as “ZERO.” When the reported value is indicated as less than (M), state the visibility as “LESS THAN” followed by the indicated value. Announce the separate digits of whole numbers as applicable.

    EXAMPLE-

    Contraction

    Phraseology

    0 SM

    VISIBILITY ZERO

    1/16 SM

    VISIBILITY ONE SIXTEENTH

    1/8 SM

    VISIBILITY ONE EIGHTH

    M ¼ SM

    VISIBILITY LESS THAN ONE QUARTER

    ¾ SM

    VISIBILITY THREE QUARTERS

    1 ½ SM

    VISIBILITY ONE AND ONE-HALF

    8 SM

    VISIBILITY EIGHT

    25 SM

    VISIBILITY TWO FIVE

  6. Runway visual range (RVR).
    1. Provide RVR information by stating the runway, the abbreviation “R-V-R,” and the indicated value.
    2. A “V” between two RVR values is announced as “VARIABLE.” When indicated, preface the values with the word “VARIABLE,” followed by the first value, the word “TO,” and then the second value.
    3. When issued along with other weather elements, transmit these values in the normal sequence used for weather reporting.

      EXAMPLE-

      RVR

      Phraseology

      R18/2000V3000FT

      RUNWAY ONE EIGHT, R-V-R VARIABLE TWO THOUSAND TO THREE THOUSAND

      R26R/2400FT

      RUNWAY TWO SIX RIGHT, R-V-R TWO THOUSAND FOUR HUNDRED

    4. When there is a requirement to issue an RVR value and a visibility condition greater than (P) or less than (M) the reportable values of the equipment is indicated, state the condition as “MORE THAN” or “LESS THAN” the appropriate minimum or maximum readable value.

      EXAMPLE-

      RVR

      Phraseology

      R16/M0600FT

      RUNWAY ONE SIX, R-V-R LESS THAN SIX HUNDRED

      R36L/M0600V2500FT

      RUNWAY THREE SIX LEFT, R-V-R VARIABLE LESS THAN SIX HUNDRED TO TWO THOUSAND FIVE HUNDRED

      R36/P6000FT

      RUNWAY THREE SIX, R-V-R MORE THAN SIX THOUSAND

  7. Weather elements. TBL 2-4-1 depicts sample phraseology for weather element contractions. Intensity refers to precipitation, not descriptors. Announce proximity after the phenomenon to which it refers. Announce descriptors ahead of weather phenomena with the exception of “showers,” which are announced after precipitation. TBL 2-4-2 contains a complete list of weather elements and appropriate phraseology.

    TBL 2-4-1
    Examples of Combining Intensity, Descriptors, and Weather Phenomenon

    Contractions

    Phraseology

    BLSN

    BLOWING SNOW

    -FZRAPL

    LIGHT FREEZING RAIN, ICE PELLETS

    FZRA

    FREEZING RAIN

    FZDZ

    FREEZING DRIZZLE

    MIFG

    SHALLOW FOG

    -SHRA

    LIGHT RAIN SHOWERS

    SHRA

    RAIN SHOWERS

    SHSN

    SNOW SHOWERS

    TSRA

    THUNDERSTORM, RAIN

    +TSRA

    THUNDERSTORM, HEAVY RAIN (SHOWERS)1

    +TSRAGR

    THUNDERSTORM, HEAVY RAIN, HAIL

    VCSH

    SHOWERS IN THE VICINITY

    1Since thunderstorms imply showery precipitation, “showers” may be used to describe precipitation that accompanies thunderstorms.

    TBL 2-4-2
    Weather Elements

    Intensity or Proximity

    1

    Descriptor

    2

    Precipitation

    3

    Obscuration

    4

    Other

    5

    -

    Light

    MI

    Shallow

    DZ

    Drizzle

    BR

    Mist

    PO

    Well-developed dust/sand whirls

    BC

    Patchy

    RA

    Rain

    FG

    Fog

    SQ

    Squalls

    Moderate (no qualifier)

    DR

    Low Drifting

    SN

    Snow

    FU

    Smoke

    FC

    +FC

    Funnel cloud, tornado, or
    waterspout

    BL

    Blowing

    SG

    Snow grains

    DU

    Dust

    SS

    Sandstorm

    +

    Heavy

    SH

    Showers

    IC

    Ice crystals

    SA

    Sand

    DS

    Duststorm

    TS

    Thunderstorm

    PL

    Ice pellets

    HZ

    Haze

    VC

    In the vicinity

    FZ

    Freezing

    GR

    Hail

    PY

    Spray

    PR

    Partial

    GS

    Snow pellets

    VA

    Volcanic Ash

    UP

    *Unknown precipitation

    *Automated stations only.

  8. Ceiling and sky coverage.
    1. State sky coverage in the same order as reported on the weather observation. Announce ceiling as shown on TBL 2-4-3.

      TBL 2-4-3
      Ceiling and Sky Coverage

      Designator

      Phraseology

      BKN0001

      SKY PARTIALLY OBSCURED

      BKN0002

      CEILING LESS THAN FIVE ZERO BROKEN

      FEW0001

      SKY PARTIALLY OBSCURED

      FEW0002

      FEW CLOUDS AT LESS THAN FIVE ZERO

      (lowest layer aloft) BKN/OVC

      (precede with) CEILING

      SCT0001

      SKY PARTIALLY OBSCURED

      SCT0002

      LESS THAN FIVE ZERO SCATTERED

      VV

      INDEFINITE CEILING

      1Surface-based obscurations; requires remarks (for example, RMK FG SCT000, FU BKN000).

      2No remark means the layer is aloft.

    2. State cloud heights in tens, hundreds and/or thousands of feet.

      EXAMPLE-

      Designator

      Phraseology

      0001

      ZERO

      003

      THREE HUNDRED

      018

      ONE THOUSAND EIGHT HUNDRED

      200

      TWO ZERO THOUSAND

      1Spoken as zero only when used with VV.

    3. Announce sky conditions as indicated in TBL 2-4-4.

      TBL 2-4-4
      Sky Conditions

      Contraction

      Phraseology

      BKN

      (height) BROKEN

      CLR1

      CLEAR BELOW ONE TWO THOUSAND

      FEW

      FEW CLOUDS AT (height)

      OVC

      (height) OVERCAST

      SCT

      (height) SCATTERED

      SKC

      CLEAR

      1Automated weather reports.

    4. The following are examples of phraseology of ceiling and sky conditions.

      EXAMPLE-

      Condition

      Phraseology

      BKN000 BKN010 BKN050 RMK FG BKN000

      SKY PARTIALLY OBSCURED, CEILING ONE THOUSAND BROKEN, FIVE THOUSAND BROKEN, FOG OBSCURING FIVE TO SEVEN EIGHTS OF THE SKY

      BKN010

      CEILING ONE THOUSAND BROKEN

      SCT000 SCT020 OVC035 RMK FG SCT000

      SKY PARTIALLY OBSCURED, TWO THOUSAND SCATTERED, CEILING THREE THOUSAND FIVE HUNDRED OVERCAST, FOG OBSCURING THREE TO FOUR EIGHTS OF THE SKY

      SCT020 OVC250

      TWO THOUSAND SCATTERED, CEILING TWO FIVE THOUSAND OVERCAST

      VV000

      INDEFINITE CEILING ZERO

      VV012

      INDEFINITE CEILING ONE THOUSAND TWO HUNDRED

  9. Temperature and dew point. Announce surface temperature and dew point by stating the words “TEMPERATURE” or “DEW POINT,” as appropriate, followed by the temperature in degrees Celsius. Announce temperatures below zero by prefixing the word “MINUS” before the values.

    EXAMPLE-

    Reading

    Phraseology

    02/M01

    TEMPERATURE TWO, DEW POINT MINUS ONE

    04/02

    TEMPERATURE FOUR, DEW POINT TWO

    18/13

    TEMPERATURE ONE EIGHT, DEW POINT ONE THREE

  10. Altimeter setting.
    1. State the word “ALTIMETER” followed by the four digits of the altimeter setting.

      EXAMPLE-

      Altimeter Setting

      Phraseology

      A2989

      ALTIMETER TWO NINER EIGHT NINER

      A3001

      ALTIMETER THREE ZERO ZERO ONE

      A3025

      ALTIMETER THREE ZERO TWO FIVE

    2. Identify the source of all altimeter settings when issued, if not given as part of an identified surface observation. Provide the time of the report if more than one hour old.
    3. If a request for the altimeter setting in millibars is received, announce the separate digits of the millibars equivalent value, using the millibars conversion chart, followed by the word “MILLIBARS.” If the millibars setting is not a whole number, always round down.

      EXAMPLE-

      Millibar Conversion

      Phraseology

      956.3

      ALTIMETER NINER FIVE SIX MILLIBARS

      1002.0

      ALTIMETER ONE ZERO ZERO TWO MILLIBARS

      1058.9

      ALTIMETER ONE ZERO FIVE EIGHT MILLIBARS

    4. When altimeter is in excess of 31.00:
      1. Advise all aircraft.
      2. Advise VFR aircraft to set altimeter to 31.00 en route.

2-4-2. ANNOUNCING MISSING ITEMS

With the exception of the RVR, announce the word “MISSING” when any item or component of a weather report is not reported, or in place of unreadable or obviously incorrect items or portions of weather reports. When appropriate, instead of speaking the name of several locations with missing reports, announce “other scheduled reports missing.”

2-4-3. WEATHER REMARKS

Announce pertinent remarks from surface weather observations in accordance with FAA Order JO 7340.2, Contractions, and as shown in the following tables. Do not state additive data or other information intended for NWS analysis or processing that does not contribute to the description of the conditions occurring at the station.

  1. Sky and ceiling.

    EXAMPLE-

    Contraction

    Phraseology

    CIG 005V010

    CEILING VARIABLE BETWEEN FIVE HUNDRED AND ONE THOUSAND

    CIG 020 RY11

    CEILING TWO THOUSAND AT RUNWAY ONE ONE

    CB N MOV E

    CUMULONIMBUS NORTH MOVING EAST

    CBMAM DSNT S

    CUMULONIMBUS MAMMATUS DISTANT SOUTH

    CLDS TPG MT SW

    CLOUDS TOPPING MOUNTAIN SOUTHWEST

    CONTRAILS N FL420

    CONDENSATION TRAILS NORTH AT FLIGHT LEVEL FOUR TWO ZERO

    FRQ LTCIC VC

    FREQUENT LIGHTNING IN CLOUD IN THE VICINITY

    LWR CLDS NE

    LOWER CLOUDS NORTHEAST

    OCNL LTGICCG NW

    OCCASIONAL LIGHTNING IN CLOUD AND CLOUD TO GROUND NORTHWEST

    RDGS OBSCD W-N

    RIDGES OBSCURED WEST THROUGH NORTH

  2. Obscuring phenomena.

    EXAMPLE-

    Contraction

    Phraseology

    BLSN SCT000

    BLOWING SNOW OBSCURING THREE TO FOUR-EIGHTS OF THE SKY

    DU BKN000

    DUST OBSCURING FIVE TO SEVEN-EIGHTS OF THE SKY

    FG FU FEW000

    FOG AND SMOKE OBSCURING ONE TO TWO-EIGHTS OF THE SKY

    FU SCT020

    SMOKE LAYER TWO THOUSAND SCATTERED

    SN BKN000

    SNOW OBSCURING FIVE TO SEVEN-EIGHTS OF THE SKY

  3. Visibility.

    EXAMPLE-

    Contraction

    Phraseology

    SFC VIS 1/2

    SURFACE VISIBILITY ONE-HALF

    SFC VIS 15 TWRINC

    SURFACE VISIBILITY ONE FIVE, TOWER IN CLOUDS

    TWR VIS 3/4

    TOWER VISIBILITY THREE-QUARTERS

    VIS S 1 W 1/4

    VISIBILITY SOUTH ONE, WEST ONE-QUARTER

    VIS 1V3

    VISIBILITY VARIABLE BETWEEN ONE AND THREE

  4. Weather and obstructions to visibility.

    EXAMPLE-

    Contraction

    Phraseology

    BCFG S

    PATCHY FOG SOUTH

    DUST DEVILS NW

    DUST DEVILS NORTHWEST

    FG DSIPTG

    FOG DISSIPATING

    FU DRFTG OVR FLD

    SMOKE DRIFTING OVER FIELD

    FUOCTY

    SMOKE OVER CITY

    GR 2

    HAILSTONES TWO INCHES IN DIAMETER

    INTMT -RA

    INTERMITTENT LIGHT RAIN

    OCNL LTG DSNT

    NW

    OCCASIONAL LIGHTNING DISTANT NORTHWEST

    OCNL SHRA

    OCCASIONAL MODERATE RAIN SHOWERS

    -RA OCNLY +RA

    LIGHT RAIN OCCASIONALLY HEAVY

    RAB30

    RAIN BEGAN AT THREE ZERO

    SNB15E40

    SNOW BEGAN AT ONE FIVE, ENDED AT FOUR ZERO

    SNINCR 5/10

    SNOW INCREASE FIVE INCHES DURING PAST HOUR, TEN INCHES ON THE GROUND

    TS OHD MOV E

    THUNDERSTORM OVERHEAD, MOVING EAST

    FRQ LTGCG TS W

    MOV E

    FREQUENT LIGHTNING CLOUD TO GROUND, THUNDERSTORM WEST MOVING EAST

    UNCONFIRMED TORNADO 15W OKC MOV NE 2015

    UNCONFIRMED TORNADO ONE FIVE WEST OF OKLAHOMA CITY,

    MOVING NORTHEAST SIGHTED AT TWO ZERO ONE FIVE ZULU

    WET SN

    WET SNOW

  5. Wind.

    EXAMPLE-

    Contraction

    Phraseology

    PK WND 33048/22

    PEAK WIND THREE THREE ZERO AT FOUR EIGHT OCCURRED AT TWO TWO PAST THE HOUR

    WSHFT 30

    WIND SHIFTED AT THREE ZERO

  6. Pressure.

    EXAMPLE-

    Contraction

    Phraseology

    PRESFR

    PRESSURE FALLING RAPIDLY

    PRESRR

    PRESSURE RISING RAPIDLY

  7. Maintenance data.

    EXAMPLE-

    RVR

    Phraseology

    PNO

    PRECIPITATION AMOUNT NOT AVAILABLE

    RVRNO

    R-V-R INFORMATION NOT AVAILABLE

    TSNO

    THUNDERSTORM/LIGHTNING INFORMATION NOT AVAILABLE

    VISNO

    VISIBILITY SENSOR INFORMATION NOT AVAILABLE

2-4-4. WEATHER ADVISORIES

  1. When announcing weather advisories, include the complete advisory description including the product name and alphanumeric identification. Specify eastern, central, or western section if applicable.
  2. Do not read the OUTLOOK section of Convective SIGMETs when stating the advisory. Data contained in the OUTLOOK concerning convective activity location, movement, and intensity may be extracted for compilation in forecast summarizations.
  3. VFR Flight Not Recommended (VNR). When VFR flight is proposed and sky conditions or visibilities are reported or forecast, surface or aloft, that, in your judgment, would make flight under VFR doubtful, include one of the following statements:

2-4-5. RADAR

When stating precipitation intensity from a radar display (for example, NEXRAD), use the following four categories as appropriate:

  1. Light (equates to radar return levels of less than 30 dBZ).
  2. Moderate (equates to radar return levels of 30 to 40 dBZ).
  3. Heavy (equates to radar return levels of greater than 40 to 50 dBZ).
  4. Extreme (equates to radar return levels of greater than 50 dBZ).

2-4-6. WINDS AND TEMPERATURES ALOFT FORECAST

When announcing the winds and temperatures aloft forecast, use the following phraseology and procedures:

  1. State the altitude, then announce wind direction and speed by the separate digits of the wind direction to the 5- or 10-degree multiple, the word “AT,” and the separate digits of the speed.
  2. When the forecast speed is less than five knots, the coded group is 9900 and read “LIGHT AND VARIABLE.”
  3. Encoded wind speed 100 to 199 knots have 50 added to the direction code and 100 subtracted from the speed.
  4. If wind speed is forecast at 200 knots or greater, the wind group is coded as 199 knots.
  5. A six-digit group includes forecast temperature. Provide temperatures on request only, stating the word ”TEMPERATURE,” followed by the word “MINUS,” as appropriate, and the separate digits.

    EXAMPLE-

    Coded

    Phraseology

    2707

    (altitude) TWO SEVEN ZERO AT SEVEN

    7799

    (altitude) TWO SEVEN ZERO AT ONE NINER NINER OR GREATER

    850552

    (altitude) THREE FIVE ZERO AT ONE ZERO FIVE, TEMPERATURE MINUS FIVE TWO

    9900+00

    (altitude) LIGHT AND VARIABLE, TEMPERATURE ZERO