12.1 General
The coding standards in this chapter conform to WMO Code Forms METAR FM 15-IX Ext. and SPECI FM 16-IX Ext. and the United States Exceptions filed with the WMO. These exceptions reflect national observing practices which differ from practices outlined in the WMO Manual on Codes No. 306.
12.2 Scope
This chapter contains the standards for coding a weather observation in either aviation routine weather report (METAR) and/or aviation selected special weather report (SPECI) format.
12.3 METAR/SPECI Code
METAR or SPECI_CCCC_YYGGggZ_AUTO or COR_dddff(f)Gfmfm(fm)KT_dndndnVdxdxdx_ VVVVVSM_[RDRDR/VRVRVRVRFT or RDRDR/VNVNVNVNVVXVXVXVXFT]_w'w'_[NsNsNshshshs or VVhshshs or SKC/CLR]_T'T'/T'dT'd_APHPHPHPH _RMK_(Automated, Manual, Plain Language)_ (Additive Data and Automated Maintenance Indicators)
METAR/SPECI has two major sections: the Body (consisting of a maximum of 11 groups) and the Remarks (consisting of 2 categories). Together, the body and remarks make up the complete METAR/SPECI. In general, the remarks are coded in the order depicted above and established in the remainder of this chapter.
12.4 Format and Content of the METAR/SPECI
a. Body of report.
(1) Type of Report - METAR/SPECI
(2) Station Identifier - CCCC
(3) Date and Time of Report - YYGGggZ
(4) Report Modifier - AUTO/COR
(5) Wind - dddff(f)Gfmfm(fm)KT_dndndnVdxdxdx
(6) Visibility - VVVVVSM
(7) Runway Visual Range - RDRDR/VRVRVRVRFT or
RDRDR/VNVNVNVNVVXVXVXVXFT
(8) Present Weather - w'w'
(9) Sky Condition - NsNsNshshshs or VVhshshs or SKC/CLR
(10) Temperature and Dew Point - T'T'/T'dT'd
(11) Altimeter - APHPHPHPH
b. Remarks section of report--RMK
(1) Automated, Manual, and Plain Language
(2) Additive and Maintenance Data
The underline character "_" indicates a required space between the groups. If a group is not reported, the preceding space is also not reported. In addition to the format given, agencies shall provide for the inclusion of any special Beginning-of-Message, End-of-Message, or End-of-Transmission signals required by their communications system.
The actual content of a METAR or SPECI depends on the observation program at the individual station. At designated stations, the 0000, 0600, 1200, and 1800 Coordinated Universal Time (UTC) METAR's include additional data specified by the responsible agency and are known as 6-hourly reports. At designated stations, the 0300, 0900, 1500, and 2100 UTC METAR's are known as 3-hourly reports and also contain additional information specified by the responsible agency.
12.5 Coding Missing Data in METAR/SPECI
When an element does not occur, or cannot be observed, the corresponding group and preceding space are omitted from that particular report.
12.6 Coding the Body of the METAR/SPECI
12.6.1 Type of Report (METAR and SPECI). The type, METAR or SPECI, shall be included in all reports. The type of report shall be separated from elements following it by a space. Whenever SPECI criteria are met at the time of the routine METAR, the type of report shall be METAR.
12.6.2 Station Identifier (CCCC). The station identifier, CCCC, shall be included in all reports to identify the station to which the coded report applies. The station identifier shall consist of four alphabetic-only characters if the METAR/SPECI is transmitted long-line. The agency with operational control when the station is first established shall be responsible for coordinating the location identifier with the FAA. A list of approved identifiers can be found in the FAA Manual 7350 Series, Location Identifiers.
12.6.3 Date and Time of Report (YYGGggZ). The date, YY, and time, GGgg, shall be included in all reports. The time shall be the actual time of the report or when the criteria for a SPECI is met or noted (see paragraph 2.6.4). If the report is a correction to a previously disseminated report, the time of the corrected report shall be the same time used in the report being corrected. The date and time group always ends with a Z indicating Zulu time (or UTC). For example, METAR KDCA 210855Z would be the 0900 scheduled report from station KDCA taken at 0855 UTC on the 21st of the month.
12.6.4 Report Modifier (AUTO or COR). The report modifier, AUTO, identifies the METAR/SPECI as a fully automated report with no human intervention or oversight. In the event of a corrected METAR or SPECI, the report modifier, COR, shall be substituted in place of AUTO.
12.6.5 Wind Group (dddff(f)Gfmfm(fm)KT_dndndnVdxdxdx). The standards for observing and reporting wind are described in Chapter 5.
The wind direction, ddd, shall be coded in tens of degrees using three figures. Directions less than 100 degrees shall be preceded with a "0". For example, a wind direction of 90 is coded as "090". The wind speed, ff(f), shall be coded in two or three digits immediately following the wind direction. The wind speed shall be coded, in whole knots, using the units and tens digits and, if required, the hundreds digit. Speeds of less than 10 knots shall be coded using a leading zero. The wind group shall always end with KT to indicate that wind speeds are reported in knots. For example, a wind speed of 8 knots shall be coded "08KT"; a wind speed of 112 knots shall be coded "112KT".
a. Gust. Wind gusts shall be coded in the format,
Gfmfm(fm) (see paragraphs 5.4.4 and 5.5.4). The wind
gust shall be coded in two or three digits immediately
following the wind speed. The wind gust shall be coded, in
whole knots, using the units and tens digits and, if required,
the hundreds digit. For example, a wind from due west at
20 knots with gusts to 35 knots would be coded "27020G35KT".
b. Variable Wind Direction (Speeds 6 knots or less). Variable
wind direction with wind speed 6 knots or less may be coded as
VRB in place of the ddd (see paragraphs 5.4.2 and
5.5.3). For example, if the wind is variable at three knots,
it would be coded "VRB03KT".
c. Variable Wind Direction (Speeds greater than 6 knots).
Variable wind direction with wind speed greater than 6 knots
shall be coded in the format, dndndnVdxdxdx. The variable
wind direction group shall immediately follow the wind group
(see paragraphs 5.4.2 and 5.5.3). The directional variability
shall be coded in a clockwise direction. For example, if
the wind is variable from 180 to 240 at 10 knots, it would be
coded "21010KT 180V240".
d. Calm Wind. Calm wind shall be coded as "00000KT"
(see paragraph 5.5.2).
12.6.6 Visibility Group (VVVVVSM). The standards for observing and reporting visibility are described in Chapter 6.
The surface visibility, VVVVVSM, shall be coded in statute miles using the values listed in Table 12- 1. A space shall be coded between whole numbers and fractions of reportable visibility values. The visibility group shall always end with SM to indicate that the visibility is in statute miles. For example, a visibility of one and a half statute miles would be coded "1 1/2SM".
Automated stations shall use an M to indicate "less than" when reporting visibility. For example, "M1/4SM" means a visibility of less than one-quarter statute mile.
| Source of Visibility Report | |||||||
|---|---|---|---|---|---|---|---|
| Automated | Manual | ||||||
| M¼ | 2 | 9¹ | 0 | 5/8 | 1 5/8 | 4 | 12 |
| ¼ | 2½ | 10 | 1/16 | ¾ | 1¾ | 5 | 13 |
| ½ | 3 | 1/8 | 7/8 | 1 7/8 | 6 | 14 | |
| ¾ | 4 | 3/16 | 1 | 2 | 7 | 15 | |
| 1 | 5 | ¼ | 1 1/8 | 2¼ | 8 | 20 | |
| 1¼ | 6¹ | 5/16 | 1¼ | 2½ | 9 | 25 | |
| 1½ | 7 | 3/8 | 1 3/8 | 2¾ | 10 | 30 | |
| 1¾ | 8¹ | ½ | 1½ | 3 | 11 | 35² | |
| Note 1: These values may not be reported by some automated stations. Note 2: Further values in increments of 5 statue mailes may be reported, i.e., 40, 45, 50, etc. |
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12.6.7. Runway Visual Range Group (RDRDR/VRVRVRVRFT or RDRDR/VnVnVnVnVVxVxVxVxFT). The standards for observing and reporting Runway Visual Range (RVR) are described in Chapter 7.
a. RVR shall be coded in the format RDRDR/VRVRVRVRFT,
where R indicates that the runway number follows,
DRDR is the runway number (an additional DR may
be used for runway approach directions, such as R for
right, L for left, and C for center), VRVRVRVR
is the constant reportable value, and FT indicates that
units of measurement are feet. A solidus "/" without spaces
separates the runway number from the constant reportable value.
For example, an RVR value for runway 01L of 800 feet would be
coded "R01L/0800FT".
b. RVR that is varying shall be coded in the format,
RDRDR/VnVnVnVnVVxVxVxVxFT, where R indicates that
the runway number follows, DRDR is the runway number
(an additional DR may be used for runway approach directions,
such as R for right, L for left, and C for
center), VnVnVnVn is the lowest reportable value in feet,
V separates lowest and highest visual range values,
VxVxVxVx is the highest reportable value, and FT
indicates that units of measurement are feet. A solidus "/"
without spaces separates the runway number from the reportable
values. For example, the 10-minute RVR for runway 01L varying
between 600 and 1,000 feet would be coded "R01L/0600V1000FT".
c. The values shall be based on light setting 5 at manual stations
regardless of the light setting actually in use (see Appendix D).
RVR values shall be coded in increments of 100 feet up to 1,000
feet, increments of 200 feet from 1,000 feet to 3,000 feet, and
increments of 500 feet from 3,000 feet to 6,000 feet. Manual
RVR shall not be reported below 600 feet. For automated stations,
RVR may be reported from up to four designated runways.
d. If the RVR is less than its lowest reportable value, the
VRVRVRVR or VnVnVnVn groups shall be preceded by
M. If the RVR is greater than its highest reportable value,
the VRVRVRVR or VxVxVxVx groups shall be preceded by
a P. For example, an RVR for runway 01L of less than 600
feet will be coded "R01L/M0600FT"; an RVR for runway 27 of greater
than 6,000 feet will be coded "R27/P6000FT".
12.6.8 Present Weather Group (w'w'). The standards for observing and reporting present weather are described in Chapter 8.
The appropriate notations found in Table 12-2 shall be used to code present weather.
| QUALIFIER | WEATHER PHENOMENA | |||
|---|---|---|---|---|
| INTENSITY OR PROXIMITY 1 |
DESCRIPTOR 2 |
PRECIPITATION 3 |
OBSCURATION 4 |
OTHER 5 |
- Light Moderate (see note 2) + Heavy VC In the Vicinity (see note 3) |
MI Shallow PR Partial BC Patches DR Low Drifting BL Blowing SH Shower(s) TS Thunderstorm FZ Freezing |
DZ Drizzle RA Rain SN Snow SG Snow Grains IC Ice Crystals PE Ice Pellets GR Hail GS Small Hail and/or Snow Pellets UP Unknown Precipitation |
BR Mist FG Fog FU Smoke VA Volcanic Ash DU Widespread Dust SA Sand HZ Haze PY Spray |
PO Well- Developed Dust/Sand Whirls SQ Squalls FC Funnel Cloud Tornado Waterspout (see note 4) SS Sandstorm SS Duststorm |
1. The weather groups shall be constructed by considering columns 1 to 5 in the table above in sequence, i.e. intensity, followed by description, followed by weather phenomena, e.g. heavy rain shower(s) is coded as +SHRA 2. To denote moderate intensity no entry or symbol is used. 3. See paragraph 8.4.1.a.(2), 8.5, and 8.5.1 for vicinity definitions. 4. Tornados and waterspouts shall be coded as +FC. |
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The following general rules apply when coding present weather for a METAR or SPECI:
a. Intensity or Proximity Qualifier.
(1) Intensity shall be coded with precipitation types, except ice crystals and hail,
including those associated with a thunderstorm (TS) and those of a showery nature
(SH). Tornadoes and waterspouts shall be coded as +FC. No intensity
shall be ascribed to the obscurations of blowing dust (BLDU), blowing sand
(BLSA), and blowing snow (BLSN). Only moderate or heavy intensity
shall be ascribed to sandstorm (SS) and duststorm (DS).
(2) The proximity qualifier for vicinity, VC, (weather phenomena observed in
the vicinity of but not at the point(s) of observation) shall be coded in
combination with thunderstorm (TS), fog (FG), shower(s) (SH),
well-developed dust/sand whirls (PO), blowing dust (BLDU), blowing
sand (BLSA), blowing snow (BLSN), sandstorm (SS), and
duststorm (DS). Intensity qualifiers shall not be coded with VC.
VCFG shall be coded to report any type of fog in the vicinity of the
point(s) of observation.
Precipitation not occurring at the point of observation but within 10 statute
miles shall be coded as showers in the vicinity (VCSH).
b. Descriptor Qualifier. Only one descriptor shall be coded for each weather
phenomena group, e.g., "-FZDZ". Mist (BR) shall not be coded with any
descriptor.
(1) The descriptors shallow (MI), partial (PR), and patches (BC)
shall only be coded with FG, e.g., "MIFG".
(2) The descriptors low drifting (DR) and blowing (BL) shall only
be coded with dust (DU), sand (SA), and snow (SN), e.g.,
"BLSN" or "DRSN". DR shall be coded for DU, SA, or
SN raised by the wind to less than six feet above the ground.
When blowing snow is observed with snow falling from clouds, both phenomena are
reported, e.g., "SN BLSN". If there is blowing snow and the observer cannot
determine whether or not snow is also falling, then BLSN shall be
reported. PY shall be coded only with blowing (BL).
(3) The descriptor shower(s) (SH) shall be coded only with one or more
of the precipitation types of rain (RA), snow (SN), ice
pellets (PE), small hail (GS), or large hail (GR).
The SH descriptor indicates showery-type precipitation. When
any type of precipitation is coded with VC, the intensity and
type of precipitation shall not be coded.
(4) The descriptor thunderstorm (TS) may be coded by itself, i.e.,
a thunderstorm without associated precipitation, or it may be coded
with the precipitation types of rain (RA), snow (SN),
ice pellets (PE), small hail and/or snow pellets (GS),
or hail (GR). For example, a thunderstorm with snow and small
hail and/or snow pellets would be coded as "TSSNGS". TS shall
not be coded with SH.
(5) The descriptor freezing (FZ) shall only be coded in combination
with fog (FG), drizzle (DZ), or rain (RA), e.g.,
"FZRA". FZ shall not be coded with SH.
c. Precipitation. Up to three types of precipitation may be coded in
a single present weather group. They shall be coded in order of decreasing
dominance based on intensity.
(1) Drizzle shall be coded as DZ; rain shall be coded as RA;
snow shall be coded as SN; snow grains shall be coded as
SG; ice crystals shall be coded as IC; ice pellets shall
be coded as PE, hail shall be coded as GR, and small hail
and/or snow pellets shall be coded as GS.
(2) At automated stations, precipitation of unknown type shall be coded as
UP.
d. Obscuration.
(1) Mist shall be coded as BR; fog shall be coded as FG;
smoke shall be coded as FU; volcanic ash shall be coded as
VA; widespread dust shall be coded as DU; sand shall be
coded as SA; and haze shall be coded as HZ
(2) Shallow fog (MIFG), patches (of) fog (BCFG), and partial
fog (PRFG) may be coded with prevailing visibility of 7 statute
miles or greater.
(3) Spray shall be coded only as BLPY.
e. Other Weather Phenomena
(1) Well-developed dust/sand whirls shall be coded as PO; squalls
shall be coded as SQ; sandstorm shall be coded as SS;
and duststorm shall be coded as DS.
(2) Tornadoes and waterspouts shall be coded as +FC. Funnel clouds
shall be coded as FC.
12.6.9 Sky Condition Group (NsNsNshshshs or VVhshshs or SKC/CLR). The standards for observing and reporting sky condition are described in Chapter 9.
a. Sky condition shall be coded in the format, NsNsNshshshs, where
NsNsNs is the amount of sky cover and hshshs is the height
of the layer. There shall be no space between the amount of sky cover
and the height of the layer. Sky condition shall be coded in an ascending
order up to thefirst overcast layer. At mountain stations, if the layer
is below station level, the height of the layer shall be coded as ///.
b. Vertical visibility shall be coded in the format, VVhshshs, where
VV identifies an indefinite ceiling and hshshs is the vertical
visibility into the indefinite ceiling (see paragraphs 9.4.4, 9.4.7, and
9.5.5). There shall be no space between the group identifier and the vertical
visibility.
c. Clear skies shall be coded in the format, SKC or CLR, where
SKC is the abbreviation used by manual stations to indicate no
layers are present and CLR is the abbreviation used by automated
stations to indicate no layers are detected at or below 12,000 feet (see
paragraph 9.5.4).
Each layer shall be separated from other layers by a space. The sky cover for each layer reported shall be coded by using the appropriate reportable contraction from Table 12-3. The report of clear skies (SKC or CLR) are complete layer reports within themselves. The abbreviations FEW, SCT, BKN, and OVC shall be followed, without a space, by the height of the layer.
| Reportable Contraction | Meaning | Summation Amount of Layer |
|---|---|---|
| VV | Vertical Visibility | 8/8 |
| SKC or CLR¹ | Clear | 0 |
| FEW² | Few | 1/8 - 2/8 |
| SCT | Scattered | 3/8 - 4/8 |
| BKN | Broken | 5/8 - 7/8 |
| OVC | Overcast | 8/8 |
1. The abbreviation CLR shall be used at automated stations when no layers at or below 12,000 feet are reported; the abbreviation SKC shall be used at manual stations when no layers are reported. 2. Any layer amount less than 1/8 is reported as FEW. |
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| Range of Height Values (feet) | Reportable Increment (feet) |
|---|---|
| <=5,000 | To nearest 100 |
| >5,000 but <=10,000 | To nearest 500 |
| >10,000 | To nearest 1,000 |
At manual stations, cumulonimbus (CB) or towering cumulus (TCU) shall be appended to the associated layer. For example, a scattered layer of towering cumulus at 1,500 feet would be coded "SCT015TCU" and would be followed by a space if there were additional higher layers to code.
12.6.10 Temperature/Dew Point Group (T'T'/T'dT'd). The standards for observing and reporting temperature and dew point are given in Chapter 10. The temperature shall be separated from the dew point with a solidus "/".
The temperature and dew point shall be coded as two digits rounded to the nearest whole degree Celsius (see paragraph 2.6.3). For example, a temperature of 0.3C would be coded as "00". Sub-zero temperatures and dew points shall be prefixed with an M. For example, a temperature of 4C with a dew point of -2C would be coded as "04/M02"; a temperature of -0.5C would be coded as "M00".
If the temperature is not available, the entire temperature/dew point group shall not be coded. If the dew point is not available, the temperature shall be coded followed by a solidus "/" and no entry made for dew point. For example, a temperature of 1.5C and a missing dew point would be coded as "02/".
12.6.11 Altimeter (APHPHPHPH). The standards for observing and reporting altimeter are described in Chapter 11.
The altimeter group always starts with an A (the international indicator for altimeter in inches of mercury). The altimeter shall be coded as a four digit group immediately following the A using the tens, units, tenths, and hundredths of inches of mercury. The decimal point is not coded.
12.7 Remarks (RMK)
Remarks shall be included in all METAR and SPECI, if appropriate.
Remarks shall be separated from the body of the report by a space and the contraction RMK. If there are no remarks, the contraction RMK is not required.
METAR/SPECI remarks fall into 2 categories: (1) Automated, Manual, and Plain Language (see paragraph 12.7.1), and (2) Additive and Maintenance Data (see paragraph 12.7.2).
Remarks shall be made in accordance with the following:
a. Where plain language is called for, authorized contractions,
abbreviations, and symbols should be used to conserve time and
space. However, in no case should an essential remark, of which
the observer is aware, be omitted for the lack of readily available
contractions. In such cases, the only requirement is that the
remark be clear. For a detailed list of authorized contractions,
see FAA Order 7340 Series, Contractions.
b. Time entries shall be made in minutes past the hour if the time
reported occurs during the same hour the observation is taken.
Hours and minutes shall be used if the hour is different, or this
Handbook prescribes the use of the hour and minutes.
c. Present weather coded in the body of the report as VC may
be further described, i.e., direction from the station, if known.
Weather phenomena beyond 10 statute miles of the point(s) of
observation shall be coded as distant (DSNT) followed by the
direction from the station. For example, precipitation of unknown
intensity within 10 statute miles east of the station would be coded
as "VCSH E"; lightning 25 statute miles west of the station would be
coded as "LTG DSNT W".
d. Distance remarks shall be statute miles except for automated lightning
remarks which are in nautical miles.
e. Movement of clouds or weather, if known, shall be coded with respect
to the direction toward which the phenomena is moving. For example,
a thunderstorm moving toward the northeast would be coded as "TS MOV NE".
f. Directions shall use the eight points of the compass coded in a
clockwise order.
g. Insofar as possible, remarks shall be entered in the order they are
presented in the following paragraphs.
12.7.1 Automated, Manual, and Plain Language Remarks. These remarks generally elaborate on parameters reported in the body of the report. Automated and manual remarks may be generated either by an automated or manual station. Plain language remarks are only provided from manual stations.
a. Volcanic Eruptions (Plain Language). Volcanic eruptions shall be coded.
The remark shall be plain language and contain the following, if known:
(1) Name of volcano.
(2) Latitude and longitude or the direction and the approximate
distance from the station.
(3) Date/Time (UTC) of the eruption.
(4) Size description, approximate height, and direction of
movement of the ash cloud.
(5) Any other pertinent data about the eruption.
For example, a remark on a volcanic eruption would look like
the following:
MT. AUGUSTINE VOLCANO 70 MILES SW ERUPTED 231505 LARGE ASH CLOUD
EXTENDING TO APRX 30000 FEET MOVING NE.
Pre-eruption volcanic activity shall not be coded. Pre-eruption
refers to unusual and/or increasing volcanic activity which
could presage a volcanic eruption.
b. Funnel Cloud (Tornadic activity_B/E(hh)mm_LOC/DIR_(MOV)). At
manual stations, tornadoes, funnel clouds, or waterspouts shall be
coded in the format, Tornadic activity_B/E(hh)mm_LOC/DIR_(MOV),
where TORNADO, FUNNEL CLOUD, orWATERSPOUT identifies the
specific tornadic activity, B/E denotes the beginning and/or
ending time, (hh)mm is the time of occurrence (only the minutes
are required if the hour can be inferred from the report time), LOC/DIR
is the location and/or direction of the phenomena from the station,
and MOV is the movement, if known (see paragraphs 8.3.3.c, 8.5.3.c,
and 8.5.5.b). Tornadic activity shall be coded as the first remark after
the "RMK" entry. For example, "TORNADO B13 6 NE" would indicate that a
tornado, which began at 13 minutes past the hour, was 6 statute miles
northeast of the station.
c. Type of Automated Station (AO1 or AO2). AO1 or AO2
shall be coded in all METAR/SPECI from automated stations. Automated
stations without a precipitation discriminator shall be identified as
AO1; automated station with a precipitation discriminator shall
be identified as AO2.
d. Peak Wind (PK_WND_dddff(f)/(hh)mm). The peak wind shall be coded
in the format,PK_WND dddff(f)/(hh)mm of the next METAR, where PK_WND
is the remark identifier, ddd is the direction of the peak wind,
ff(f) is the peak wind speed since the last METAR, and (hh)mm is
the time of occurrence (only the minutes are required if the hour can be
inferred from the report time) (see paragraphs 5.4.5 and 5.5.5). There
shall be a space between the two elements of the remark identifier and the
wind direction/speed group; a solidus "/" (without spaces) shall
separate the wind direction/speed group and the time. For example, a peak
wind of 45 knots from 280 degrees that occurred at 15 minutes past the hour
would be coded "PK WND 28045/15".
e. Wind Shift (WSHFT_(hh)mm). A wind shift shall be coded in the format,
WSHFT_(hh)mm, where WSHFT is the remark identifier and (hh)mm
is the time the wind shift began (only the minutes are required if the hour
can be inferred from the report time) (see paragraphs 5.4.6 and 5.5.6). The
contraction FROPA may be entered following the time if it is reasonably
certain that the wind shift was the result of a frontal passage. There shall
be a space between the remark identifier and the time and, if applicable,
between the time and the frontal passage contraction. For example, a remark
reporting a wind shift accompanied by a frontal passage that began at
30 minutes after the hour would be coded as "WSHFT 30 FROPA".
f. Tower or Surface Visibility (TWR_VIS_vvvvv or SFC_VIS_vvvvv).
Tower visibility or surface visibility (see paragraphs 6.5.4 and 6.5.5)
shall be coded in the formats, TWR_VIS_vvvvv or SFC_VIS_vvvvv,
respectively, where vvvvv is the observed tower/surface
visibility value. A space shall be coded between each of the remark
elements. For example, the control tower visibility of 1 1/2 statute
miles would be coded "TWR VIS 1 1/2".
g. Variable Prevailing Visibility (VIS_vnvnvnvnvnVvxvxvxvxvx).
Variable prevailing visibility shall be coded in the format
VIS_vnvnvnvnvnVvxvxvxvxvx, where VIS is the remark
identifier, vnvnvnvnvn is the lowest visibility evaluated,
V denotes variability between two values, and vxvxvxvxvx
is the highest visibility evaluated. There shall be one space following
the remark identifier; no spaces between the letter V and the
lowest/highest values. For example, a visibility that was varying
between 1/2 and 2 statute miles would be coded "VIS 1/2V2" (see
paragraphs 6.4.5 and 6.5.3).
h. Sector Visibility (VIS_[DIR]_vvvvv) [Plain Language]. The
sector visibility shall be coded in the format, VIS_[DIR]_vvvvv,
where VIS is the remark identifier, [DIR] defines
the sector to 8 points of the compass, and vvvvv is the sector
visibility in statute miles, using the appropriate set of values in
Table 12-1 (see paragraphs 6.4.6 and 6.5.7). For example, a visibility
of 2 1/2 statute miles in the northeastern octant would be
coded "VIS NE 2 1/2".
i. Visibility At Second Location (VIS_vvvvv_[LOC]). At designated
automated stations, the visibility at a second location shall be coded
in the format VIS_vvvvv_[LOC], where VIS is the remark
identifier, vvvvv is the measured visibility value, and [LOC]
is the specific location of the visibility sensor(s) at the station (see
paragraph 6.5.6). This remark shall only be generated when the condition
is lower than that contained in the body of the report. For example, a
visibility of 2 1/2 statute miles measured by a second sensor located at
runway 11 would be coded "VIS 2 1/2 RWY11".
j. Lightning (Frequency_LTG(type)_[LOC]).
(1) When lightning is observed at a manual station, the frequency,
type of lightning, and location shall be reported. The remark
shall be coded in the format Frequency_LTG(type)_[LOC].
The contractions for the type and frequency of lightning shall
be based on Table 12-5. The location and direction shall be coded
in accordance with paragraph 12.7.c. For example, "OCNL LTGICCG OHD",
"FRQ LTG VC", or "LTG DSNT W".
(2) When lightning is detected by an automated system:
(a) Within 5 nautical miles of the Airport Location Point (ALP),
it will be reported as TS in the body of the report
with no remark;
(b) Between 5 and 10 nautical miles of the ALP, it will be reported
as VCTS in the body of the report with no remark;
(c) Beyond 10 but less than 30 nautical miles of the ALP, it will
be reported in remarks only as LTG DSNT followed by the
direction from the ALP.
| Type of Lightning | ||
|---|---|---|
| Type | Contraction | Definition |
| Cloud-ground | CG | Lightning occurring between cloud and ground. |
| In-cloud | IC | Lightning which takes place within the cloud. |
| Cloud-cloud | CC | Streaks of lightning reaching from one cloud to another. |
| Cloud-air | CA | Streaks of lightning which pass from a cloud to air, but do not strike the ground. |
| Frequency of Lightning | ||
| Frequency | Contraction | Definition |
| Occasional | OCNL | Less than 1 flash/minute. |
| Frequent | FRQ | About 1 to 6 flashes/minute. |
| Continuous | CONS | More than 6 flashes/minute. |
k. Beginning and Ending of Precipitation (w'w'B(hh)mmE(hh)mm).
At designated stations, the beginning and ending of precipitation
shall be coded in the format, w'w'B(hh)mmE(hh)mm, where w'w'
is the type of precipitation, B denotes the beginning, E
denotes the ending, and (hh)mm is the time of occurrence (only the
minutes are required if the hour can be inferred from the report time)
(see paragraph 8.5.5.a). There shall be no spaces between the elements.
The coded remarks are not required in SPECI and should be reported in
the next METAR. Intensity qualifiers shall not be coded. For example,
if rain began at 0005, ended at 0030, and snow began at 0020, and ended
at 0055, the remarks would be coded "RAB05E30SNB20E55". If the precipitation
were showery, the remark would be coded "SHRAB05E30SHSNB20E55".
l. Beginning and Ending of Thunderstorms (TSB(hh)mmE(hh)mm). The
beginning and ending of thunderstorm(s) shall be coded in the format,
TSB(hh)mmE(hh)mm, where TS indicates thunderstorm, B
denotes the beginning, E denotes the ending, and (hh)mm
is the time of occurrence (only the minutes are required if the hour can be
inferred from the report time) (see paragraph 8.5.4). There shall be no
spaces between the elements. For example, if a thunderstorm began at 0159
and ended at 0230, the remark would be coded "TSB0159E30".
m. Thunderstorm Location (TS_LOC_(MOV_DIR)) [Plain Language].
Thunderstorm(s) shall be coded in the format, TS_LOC_(MOV_DIR),
where TS identifies the thunderstorm activity, LOC is the
location of the thunderstorm(s) from the station, and MOV_DIR is
the movement with direction, if known (see paragraph 8.4.1.b(5) and 8.5.4).
For example, a thunderstorm southeast of the station and moving toward the
northeast would be coded "TS SE MOV NE".
n. Hailstone Size (GR_[size]) [Plain Language]. At designated
stations, the hailstone size shall be coded in the format, GR_[size],
where GR is the remark identifier and [size] is the
diameter of the largest hailstone. The hailstone size shall be coded in
1/4 inch increments (see paragraph 8.5.1.c(8)). For example, "GR 1 3/4"
would indicate that the largest hailstones were 1 3/4 inches in diameter.
If GS is coded in the body of the report, no hailstone size remark
is required.
o. Virga (VIRGA_(DIR)) [Plain Language]. Virga shall be coded
in the format, VIRGA_(DIR), where VIRGA is the remark
identifier and DIR is the direction from the station. The
direction of the phenomena from the station is optional, e.g., "VIRGA"
or "VIRGA SW".
p. Variable Ceiling Height (CIG_hnhnhnVhxhxhx). The variable
ceiling height shall be coded in the format, CIG_hnhnhnVhxhxhx,
where CIG is the remark identifier, hnhnhn is the
lowest ceiling height evaluated, V denotes variability between
two values, and hxhxhx is the highest ceiling height evaluated
(see paragraph 9.5.7 and Table 9-1). There shall be one space
following the remark identifier; no spaces between the
letter V and the lowest/highest ceiling values. For example,
"CIG 005V010" would indicate a ceiling that was varying between 500
and 1,000 feet.
q. Obscurations (w'w'_[NsNsNs]hshshs). [Plain Language]
Obscurations (surface-based or aloft) shall be coded in the format,
w'w'_[NsNsNs]hshshs, where w'w' is the weather causing
the obscuration at the surface or aloft, NsNsNs is the applicable sky
cover amount of the obscuration aloft (FEW, SCT, BKN, OVC) or at the
surface (FEW, SCT, BKN), and hshshs is the applicable height
(see paragraphs 9.4.3 and 9.5.6). Surface-based obscurations shall have
a height of "000". There shall be a space separating the weather
causing the obscuration and the sky cover amount; there shall be no space
between the sky cover amount and the height. For example, fog hiding
3-4 oktas of the sky would be coded "FG SCT000"; a broken layer at 2,000 feet
composed of smoke would be coded "FU BKN020".
r. Variable Sky Condition (NsNsNs(hshshs)_V_NsNsNs). [Plain Language]
The variable sky condition remark shall be coded in the format,
NsNsNs(hshshs)_V_NsNsNs, where NsNsNs(hshshs) and NsNsNs
identifies the two operationally significant sky conditions and V denotes
the variability between the two ranges (see paragraphs 9.4.2.d and 9.5.9).
If there are several layers with the same sky condition amount, the layer
height (hshshs) of the variable layer shall be coded. For example,
a cloud layer at 1,400 feet that is varying between broken and overcast would
be coded "BKN014 V OVC".
s. Significant Cloud Types [Plain Language]. The significant cloud
type remark shall be coded in all reports in the following manner (see
paragraphs 9.4.6 and 9.5.10):
(1) Cumulonimbus or Cumulonimbus Mammatus (CB or CBMAM_LOC_(MOV_DIR).
Cumulonimbus or cumulonimbus mammatus, as appropriate, (for which no
thunderstorm is being reported) shall be coded in the format, CB or
CBMAM_LOC_(MOV_DIR), where CB or CBMAM is the cloud
type, LOC is the direction from the station, and MOV_DIR is
the movement with direction (if known). The cloud type, location, movement,
and direction entries shall be separated from each other with a space.
For example, a CB up to 10 statute miles west of the station moving
toward the east would be coded "CB W MOV E". If the CB was more than
10 statute miles to the west, the remark would be coded "CB DSNT W".
(2) Towering cumulus (TCU_[DIR]). Towering cumulus clouds shall be
coded in the format, TCU_[DIR], where TCU is the cloud
type and DIR is the direction from the station. The cloud type
and direction entries shall be separated by a space. For example, a
towering cumulus cloud up to 10 statute miles west of the station would
be coded "TCU W".
(3) Altocumulus castellanus (ACC_[DIR]). Altocumulus castellanus
shall be coded in the format, ACC_[DIR], where ACC is
the cloud type and DIR is the direction from the station. The
cloud type and direction entries shall be separated by a space. For
example, an altocumulus cloud 5 to 10 statute miles northwest of the
station would be coded "ACC NW".
(4) Standing lenticular or Rotor clouds (CLD_[DIR]). Stratocumulus
(SCSL), altocumulus (ACSL), or cirrocumulus (CCSL), or rotor clouds shall
be coded in the format, CLD_[DIR], where CLD is the cloud
type and DIR is the direction from the station. The cloud type
and direction entries shall be separated by a space. For example,
altocumulus standing lenticular clouds observed southwest through west
of the station would be coded "ACSL SW-W"; an apparent rotor cloud 5 to
10 statute miles northeast of the station would be coded "APRNT ROTOR CLD
NE"; and cirrocumulus clouds south of the station would be coded "CCSL S".
t. Ceiling Height at Second Location (CIG_hhh_[LOC]). At
designated stations, the ceiling height at a second location shall be
coded in the format, CIG_hhh_[LOC], where CIG is the remark
identifier, hhh is the measured height of the ceiling, and [LOC]
is the specific location of the ceilometer(s) at the station (see paragraph
9.5.8). This remark shall only be generated when the ceiling is lower than
that contained in the body of the report. For example, if the ceiling
measured by a second sensor located at runway 11 is broken at 200 feet,
the remark would be "CIG 002RWY11".
u. Pressure Rising or Falling Rapidly (PRESRR/PRESFR). At designated
stations, when the pressure is rising or falling rapidly at the time of
observation (see paragraphs 11.4.6 and 11.5.5), the remark PRESRR
(pressure rising rapidly) or PRESFR (pressure falling rapidly) shall
be included in the report.
v. Sea-Level Pressure (SLPppp). At designated stations, the sea-level
pressure shall be coded in the format SLPppp, where SLP is
the remark identifier and ppp is the sea-level pressure in
hectopascals (see paragraphs 11.4.4 and 11.5.4). For example, a sea-level
pressure of 998.2 hectopascals would be coded as "SLP982". For a METAR, if
sea-level pressure is not available, it is coded as "SLPNO".
w. Aircraft Mishap (ACFT_MSHP) [Plain Language]. If a report is
taken to document weather conditions when notified of an aircraft mishap,
the remark ACFT_MSHP shall be coded in the report but not transmitted.
The act of non-transmission shall be indicated by enclosing the remark in
parentheses in the record, i.e., "(ACFT MSHP)".
x. No SPECI Reports Taken (NOSPECI) [Plain Language]. At manual
stations where SPECI's are not taken, the remark NOSPECI shall
be coded to indicate that no changes in weather conditions will be
reported until the next METAR.
y. Snow Increasing Rapidly (SNINCR_[inches-hour/inches on ground]).
At designated stations, the snow increasing rapidly remark shall be
reported, in the next METAR, whenever the snow depth increases by 1 inch
or more in the past hour. The remark shall be coded in the format,
SNINCR [inches-hour/inches on ground], where SNINCR is the
remark indicator, inches-hour is the depth increase in the past hour,
and inches on ground is the total depth of snow on the ground at
the time of the report. The depth increase in the past hour and the total
depth on the ground are separated from each other by a solidus "/".
For example, a snow depth increase of 2 inches in the past hour with a
total depth on the ground of 10 inches would be coded "SNINCR 2/10".
z. Other Significant Information [Plain Language]. Agencies may
add to a report other information significant to their operations, such
as information on fog dispersal operations, runway conditions, "FIRST"
or "LAST" report from station, etc.
12.7.2 Additive and Automated Maintenance Data. Additive data groups are only reported at designated stations. The maintenance data groups are only reported from automated stations.
a. Precipitation
(1) Amount of Precipitation. The amount of liquid precipitation
shall be coded as the depth of precipitation that accumulates in an
exposed vessel during the time period being evaluated. The amount
of freezing or frozen precipitation shall be the water equivalent of
the solid precipitation accumulated during the appropriate time period.
(2) Units of Measure for Precipitation. Precipitation measurements
shall be in inches, tenths of inches, or hundredths of inches
depending on the precipitation being measured (see Table 12-6).
| Type of Measurement | Unit of Measure |
|---|---|
| Liquid Precipitation | 0.01 inch |
| Water Equivalent of Solid Precipitation | 0.01 inch |
| Solid Precipitation | 0.1 inch |
| Snow Depth | 1.0 inch |
(3) Depth of Freezing or Frozen Precipitation. The depth
of freezing and/or frozen precipitation shall be the actual
vertical depth of the precipitation accumulated on a horizontal
surface during the appropriate time period (see paragraphs 12.7.2.a(3)(b)
and 12.7.2.a(3)(c). If snow falls, melts, and refreezes, the
depth of ice formed shall be included in the measurement.
(a) Hourly Precipitation Amount (Prrrr). At designated
automated stations, the hourly precipitation amount shall
be coded in the format, Prrrr, where P is the
group indicator and rrrr is the water equivalent of all
precipitation that has occurred since the last METAR (see
paragraph 12.7.2.a(1)). The amount shall be coded in
hundredths of an inch. For example, "P0009" would indicate
9/100 of an inch of precipitation fell in the past hour; "P0000"
would indicate that less than 1/100 of an inch of precipitation
fell in the past hour.
The group shall be omitted if no precipitation occurred since the
last METAR.
(b) 3- and 6-Hour Precipitation Amount (6RRRR). At designated
stations, the 3- and 6-hourly precipitation group shall be coded
in the format, 6RRRR, where 6 is the group indicator
and RRRR is the amount of precipitation. The amount of
precipitation (water equivalent) accumulated in the past 3 hours
shall be reported in the 3-hourly report; the amount accumulated
in the past 6 hours shall be reported in the 6-hourly report. The
amount of precipitation shall be coded in inches, using the tens,
units, tenths and hundredths digits of the amount. When an
indeterminable amount of precipitation has occurred during the
period, RRRR shall be coded 6////. For example, 2.17 inches
of precipitation would be coded "60217". A trace shall be
coded "60000".
(c) 24-Hour Precipitation Amount (7R24R24R24R24). At
designated stations, the 24-hour precipitation amount shall be
coded in the format, 7R24R24R24R24, where 7 is the
group indicator and R24R24R24R24 is the 24-hour precipitation
amount. The 24-hour precipitation amount shall be included in the
1200 UTC (or other agency designated time) report whenever more
than a trace of precipitation (water equivalent) has fallen in the
preceding 24 hours. The amount of precipitation shall be coded by
using the tens, units, tenths, and hundredths of inches (water
equivalent) for the 24-hour period. If more than a trace (water
equivalent) has occurred and the amount cannot be determined, the
group shall be coded 7////. For example, 1.25 inches of
precipitation (water equivalent) in the past 24 hours shall be
coded "70125".
(d) Snow Depth on Ground (4/sss). At designated stations,
the total snow depth on the ground group shall be coded in the
0000 and 1200 UTC observation whenever there is more than a trace
of snow on the ground. It shall be coded in the 0600 and 1800 UTC
observation if there is more than a trace of snow on the ground
and more than a trace of precipitation (water equivalent) has
occurred within the past 6 hours. The remark shall be coded in
the format, 4/sss, where 4/ is the group indicator
and sss is the snow depth in whole inches using three digits.
For example, a snow depth of 21 inches shall be coded as "4/021".
(e) Water Equivalent of Snow on Ground (933RRR). At
designated stations, the water equivalent of snow on the ground
shall be coded each day, in the 1800 UTC report, if the average
snow depth is 2 inches or more. Theremark shall be coded in the
format, 933RRR, where 933 is the group indicator
and RRR is the water equivalent of snow, i.e., snow, snow
pellets, snow grains, ice pellets, ice crystals, and hail, on
the ground. The water equivalent shall be coded in tens, units,
and tenths of inches, using three digits. If the water equivalent
of snow consists entirely of hail, the group shall not be coded.
A water equivalent of 3.6 inches of snow would be coded as "933036";
a water equivalent of 12.5 would be coded as "933125".
b. Cloud Types (8/CLCMCH). At designated stations, the group,
8/CLCMCH, shall be reported and coded in 3- and 6-hourly reports
when clouds are observed. The predominant low cloud (CL), middle
cloud (CM), and high cloud (CH), shall be identified in
accordance with the WMO International Cloud Atlas, Volumes I and II,
or the WMO Abridged International Cloud Atlas or agency observing
aids for cloud identification. A 0 shall be coded for the low,
middle, or high cloud type if no cloud is present in that classification.
A solidus "/" shall be coded for layers above an overcast. If no
clouds are observed due to clear skies, the cloud type group shall not
be coded. For example, a report of "8/6//" would indicate an overcast
layer of stratus clouds; a report of "8/903" would indicate cumulonimbus
type low clouds, no middle clouds, and dense cirrus high clouds.
c. Duration of Sunshine (98mmm). The duration of sunshine that
occurred the previous calendar day shall be coded in the 0800 UTC report.
If the station is closed at 0800 UTC, the group shall be coded in the
first 6-hourly METAR after the station opens. The duration of sunshine
shall be coded in the format, 98mmm, where 98 is the group
indicator and mmm is the total minutes of sunshine. The minutes
of sunshine shall be coded by using the hundreds, tens, and units digits.
For example, 96 minutes of sunshine would be coded "98096". If no
sunshine occurred, the group would be coded "98000".
d. Hourly Temperature and Dew Point (TsnT'T'T'snT'dT'dT'd). At
designated stations, the hourly temperature and dew point group shall
be coded to the tenth of a degree Celsius in the format, TsnT'T'T'snT'dT'dT'd,
where T is the group indicator, sn is the sign of the temperature,
T'T'T' is the temperature, and T'dT'dT'd is the dew point
(see paragraphs 10.5.1 and 10.5.3). The sign of the temperature and
dew point shall be coded as 1 if the value is below 0°C and 0 if the value
is 0°C or higher. The temperature and dew point shall be reported
in tens, units, and tenths of degrees Celsius. There shall be no spaces
between the entries. For example, a temperature of 2.6°C and dew
point of -1.5°C would be reported in the body of the report as
"03/M01" and the TsnT'T'T'snT'dT'dT'd group as "T00261015". If
dew point is missing report the temperature; if the temperature is missing
do not report the temperature/dew point group.
e. 6-Hourly Maximum Temperature (1snTxTxTx). At designated
stations, the 6-hourly maximum temperature group shall be coded in the
format, 1snTxTxTx, where 1 is the group indicator, sn
is the sign of the temperature, TxTxTx is the maximum temperature
in tenths of degrees Celsius using three digits (see paragraphs 10.4.4,
10.5.2, and 10.5.3). The sign of the maximum temperature shall be coded
as 1 if the maximum temperature is below 0°C and 0 if the maximum
temperature is 0°C or higher. For example, a maximum temperature
of -2.1°C would be coded "11021"; 14.2°C would be coded "10142".
f. 6-Hourly Minimum Temperature (2snTnTnTn). At designated stations,
the 6-hourly minimum temperature group shall be coded in the format,
2snTnTnTn, where 2 is the group indicator, sn is the
sign of the temperature, and TnTnTn is the minimum temperature in
tenths of degrees Celsius using three digits (see paragraphs 10.4.4,
10.5.2, and 10.5.3). The sign of the minimum temperature shall be coded
as 1 if the minimum temperature is below 0°C and 0 if the minimum
temperature is 0°C or higher. For example, a minimum temperature
of -0.1°C would be coded "21001"; 1.2°C would be coded "20012".
g. 24-Hour Maximum and Minimum Temperature (4snTxTxTxsnTnTnTn). At
designated stations, the 24-hour maximum temperature and the 24-hour
minimum temperature shall be coded in the format, 4snTxTxTxsnTnTnTn,
where 4 is the group indicator, sn is the sign of the
temperature, TxTxTx is the maximum 24-hour temperature, and TnTnTn
is the 24-hour minimum temperature (see paragraphs 10.4.4, 10.5.2, and
10.5.3). TxTxTx and TnTnTn shall be coded in tenths of
degrees Celsius using three digits. The sign of the maximum or minimum
temperature shall be coded as 1 if it is below 0°C and 0 if it
is 0°C or higher. For example, a 24-hour maximum temperature of
10.0°C and a 24-hour minimum temperature of -1.5°C would be coded
"401001015"; a 24-hour maximum temperature of 11.2°C and a 24-hour
minimum temperature of 8.4C would be coded as"401120084".
h. 3-Hourly Pressure Tendency (5appp). At designated stations, the
3-hourly pressure tendency group shall be coded in the format, 5appp,
where 5 is the group indicator, a is the character of
pressure change over the past 3 hours (see Table 12-7), and ppp
is the amount of barometric change in tenths of hectopascals (see Table 12-8).
The amount of barometric change shall be coded using the tens, units, and
tenths digits (see paragraphs 11.4.7 and 11.5.4). For example, a steady
increase of 3.2 hectopascals in the past three hours would be coded "52032".
| Primary Requirement |
Description | Code Figure |
|---|---|---|
| Atmospheric pressure now higher than 3 hours ago. |
Increasing, then decreasing. | 0 |
| Increasing, then steady, or increasing then increasing more slowly. |
1 | |
| Increasing steadily or unsteadily. | 2 | |
| Decreasing or steady, then increasing; or increasing then increasing more rapidly. |
3 | |
| Atmospheric pressure now same as 3 hours ago. |
Increasing, then decreasing. | 0 |
| Steady | 4 | |
| Decreasing then increasing. | 5 | |
| Atmospheric pressure now lower than 3 hours ago. |
Decreasing, then increasing. | 5 |
| Decreasing, then steady, or decreasing then decreasing more slowly. |
6 | |
| Decreasing steadily or unsteadily. | 7 | |
| Steady or increasing, then decreasing; or decreasing then decreasing more rapidly. |
8 |
| Amount of Barometric Change (Rise or Fall) in the Past 3 hours "ppp" | ||||||||
|---|---|---|---|---|---|---|---|---|
| Code Figure |
Inches of Mercury |
Hectopascals | Code Figure |
Inches of Mercury |
Hectopascals | Code Figure |
Inches of Mercury |
Hectopascals |
| 000 002 003 005 007 008 010 012 014 015 017 019 020 022 024 025 027 029 030 032 034 036 037 039 041 042 044 046 047 049 051 052 054 056 058 059 061 063 064 066 |
0.000 0.005 0.010 0.015 0.020 0.025 0.030 0.035 0.040 0.045 0.050 0.055 0.060 0.065 0.070 0.075 0.080 0.085 0.090 0.095 0.100 0.105 0.110 0.115 0.120 0.125 0.130 0.135 0.140 0.145 0.150 0.155 0.160 0.165 0.170 0.175 0.180 0.185 0.190 0.195 |
0.0 0.2 0.3 0.5 0.7 0.8 1.0 1.2 1.4 1.5 1.7 1.9 2.0 2.2 2.4 2.5 2.7 2.9 3.0 3.2 3.4 3.6 3.7 3.9 4.1 4.2 4.4 4.6 4.7 4.9 5.1 5.2 5.4 5.6 5.8 5.9 6.1 6.3 6.4 6.6 |
068 069 071 073 075 076 078 080 081 083 085 086 088 090 091 093 095 097 098 100 102 103 105 107 108 110 112 113 115 117 119 120 122 124 125 127 129 130 132 134 |
0.200 0.205 0.210 0.215 0.220 0.225 0.230 0.235 0.240 0.245 0.250 0.255 0.260 0.265 0.270 0.275 0.280 0.285 0.290 0.295 0.300 0.305 0.310 0.315 0.320 0.325 0.330 0.335 0.340 0.345 0.350 0.355 0.360 0.365 0.370 0.375 0.380 0.385 0.390 0.395 |
6.8 6.9 7.1 7.3 7.5 7.6 7.8 8.0 8.1 8.3 8.5 8.6 8.8 9.0 9.1 9.3 9.5 9.7 9.8 10.0 10.2 10.3 10.5 10.7 10.8 11.0 11.2 11.3 11.5 11.7 11.9 12.0 12.2 12.4 12.5 12.7 12.9 13.0 13.2 13.4 |
135 137 139 141 142 144 146 147 149 151 152 154 156 157 159 161 163 164 166 168 169 171 173 174 176 178 179 181 183 185 186 188 190 191 193 195 196 198 200 201 |
0.400 0.405 0.410 0.415 0.420 0.425 0.430 0.435 0.440 0.445 0.450 0.455 0.460 0.465 0.470 0.475 0.480 0.485 0.490 0.495 0.500 0.505 0.510 0.515 0.520 0.525 0.530 0.535 0.540 0.545 0.550 0.555 0.560 0.565 0.570 0.575 0.580 0.585 0.590 0.595 |
13.5 13.7 13.9 14.1 14.2 14.4 14.6 14.7 14.9 15.1 15.2 15.4 15.6 15.7 15.9 16.1 16.3 16.4 16.6 16.8 16.9 17.1 17.3 17.4 17.6 17.8 17.9 18.1 18.3 18.5 18.6 18.8 19.0 19.1 19.3 19.5 19.6 19.8 20.0 20.1 |
i. Sensor Status Indicators. Sensor status indicators should be
reported as indicated below:
(1) if the Runway Visual Range should be reported but is missing,
RVRNO shall be coded.
(2) when automated stations are equipped with a present weather
identifier and that sensor is not operating, the remark PWINO
shall be coded.
(3) when automated stations are equipped with a tipping bucket
rain gauge and that sensor is not operating, PNO shall
be coded.
(4) when automated stations are equipped with a freezing rain
sensor and that sensor is not operating, the remark FZRANO
shall be coded.
(5) when automated stations are equipped with a lightning detection
system and that sensor is not operating, the remark TSNO
shall be coded.
(6) when automated stations are equipped with a secondary visibility
sensor and that sensor is not operating, the remark VISNO_LOC
shall be coded.
(7) when automated stations are equipped with a secondary ceiling height
indicator and that sensor is not operating, the remark CHINO_LOC
shall be coded.
j. Maintenance Indicator. A maintenance indicator sign, $,
shall be coded when an automated system detects that maintenance is
needed on the system.