IRFP-01
Metro Review
(4) Visibility
(a) Internationally, visibility is reported in 4 digits, using
meters, with the direction of the lowest visibility sector
(e.g., 6000SW—meaning visibility is lowest at 6,000
meters to the southwest)
(b) In the United States, we use prevailing visibility in
statute miles, not the lowest visibility, so the same
conditions would be reported differently
(c) International visibility reports also contain a trend, such
as:
i)
D—Down
ii)
U—Up
iii) N—No change
iv) V—Variable
2. Other
a. Remarks (RMK) included in U.S. METAR are transmitted to
only Canada and Mexico and no other international stations
b. Pilots may also see the following notation on International
METAR/TAF: CAVOK (Ceiling and Visibility OK)
(1) CAVOK is used to replace weather and clouds if visibility is
Fig 26: METAR
10 km or more, and there are no clouds below 1,500
Abbreviations
meters (5,000 ft) or below the highest minimum air traffic
control sector altitude, whichever is greater
Fig 27: METAR
(2) Also, there must be no other significant weather. NSC
(SPECI or Special
means no significant clouds
Report)
c.
International TAFs may include temperature, turbulence, and
icing forecasts
E. Area Forecast (FA) 21.1.1.5.3
Fig 28: Area
Forecast Coverage
1. General - provides overview of aviation weather conditions over the
United States and adjacent coastal waters
a. Used for flight planning and a weather briefing aid
(8-97) Original
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