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$:maintenance needed
A:Altimeter
ACC:altocumulus castellanus
ACFT MSHP:aircraft mishap
ACSL:altocumulus standing lenticular cloud
ALP:airport location point
AMD:amended
AO1:automated station without precipitation discriminator
AO2:automated station with precipitation discriminator
APRNT:apparent
APRX:approximately
ATCT:airport traffic control tower
AUTO:automated report
B:began
BC:patches
BECMG:becoming
BKN:broken (5/8 - 7/8 coverage)
BL:blowing
BR:mist (visibility > 1/2 mile)
C:center (with reference to runway designation)
CA:cloud-air lightning
CAVOK:ceiling and visibility OK (viz >10 km, ceiling > 5000 feet, no precip)
CB:cumulonimbus cloud
CBMAM:cumulonimbus mammatus cloud
CC:cloud-cloud lightning
CCSL:cirrocumulus standing lenticular cloud
CG:cloud-ground lightning
CHI:cloud-height indicator
CHINO:sky condition at secondary location not available
CIG:ceiling
CLR:clear below 12,000 feet (automated)
CONS:continuous
COR:correction to a previously disseminated report
DOC:Department of Commerce
DOD:Department of Defense
DOT:Department of Transportation
DR:low drifting
DS:duststorm
DSNT:distant
DU:widespread dust
DZ:drizzle
E:east, ended
FAA:Federal Aviation Administration
FC:funnel cloud
FEW:few clouds (0/8 - 2/8 coverage)
FG:fog
FIBI:filed but impracticable to transmit
FIRST:first observation after a break in coverage at manual station
FROPA:frontal passage
FRQ:frequent
FT:feet
FU:smoke
FZ:freezing
FZRANO:freezing rain sensor not available
G:gust
GR:hail
GS:small hail and/or snow pellets
HZ:haze
IC:ice crystals, in-cloud lightning
ICAO:International Civil Aviation Organization
LTGIC:lightning in cloud
LTGICCG:lightning in cloud and cloud to ground
KT:knots
L:left (with reference to runway designation)
LAST:last observation before a break in coverage at a manual station
LST:Local Standard Time
LTG:lightning
LWR:lower
M:minus, less than
METAR:aviation routine weather report (observation)
MI:shallow
MOV:moved/moving/movement
MT:mountains
N:north
N/A:not applicable
NCDC:National Climatic Data Center
NE:northeast
NOS:National Ocean Service
NOSPECI:no SPECI reports are taken at the station
NSW:no significant weather
NW:northwest
NWS:National Weather Service
OCNL:occasional
OFCM:Office of the Federal Coordinator for Meteorology
OVC:overcast (8/8 coverage)
OHD:overhead
P:greater than 
PE:ice pellets
PK:peak
PK WND:peak wind
PNO:precipitation amount not available
PO:well-developed dust/sand whirls (dust devils)
PR:partial
PRESFR:pressure falling rapidly
PRESRR:pressure rising rapidly
PWINO:precipitation identifier sensor not available
PY:spray
R:right (with reference to runway designation)
RA:rain
RMK:Remarks
RVR:Runway Visual Range
RVRNO:RVR system not available
RWY:runway
S:south
SA:sand
SCSL:stratocumulus standing lenticular cloud
SCT:scattered (3/8 - 4/8 coverage)
SE:southeast
SFC:surface
SG:snow grains
SH:shower(s)
SKC:sky clear
SLP:sea-level pressure
SLPNO:sea-level pressure not available
SM:statute miles
SN:snow
SNINCR:snow increasing rapidly
SPECI:an unscheduled report taken when certain criteria have been met
SQ:squalls
SS:sandstorm
SW:southwest
TAF:routine terminal aerodrome forecast
TCU:towering cumulus
TEMPO:temporary
TESTM:AWOS METAR Test Report
TRSA:thunderstorm and rain shower
TS:thunderstorm
TSNO:thunderstorm information not available
TWR:tower
UP:unknown precipitation
UTC:Coordinated Universal Time
V:variable
VA:volcanic ash
VC:in the vicinity (5 - 10 miles from airport)
VIRGA:rain that doesn't reach ground
VIS:visibility
VISNO:visibility at secondary location not available
VRB:variable
VV:vertical visibility
W:west
WG/SO:Working Group for Surface Observations
WMO:World Meteorological Organization
WND:wind
WSHFT:wind shift
Z:zulu, i.e., Coordinated Universal Time
