OUR Manual says,
Precision Appr. RVR or Visibility counts
Non.Prec : RVR / VIS AND Ceiling
BECMG AT :
Deterioration: Applicable for the whole time
Improvement : applicable
-steady windspeed must be within limits. Gusts may be disregarded.
BECMG FROM - TO:
Deterioration: Applicable from start.
Improvement: Applicable from the end
TEMPO FROM/TO AT PROB30/40:
Deterioration:
Transient Cond. (shower): Not applicable. Wind may be disregarded.
Persistent cond. (haze, fog): applicable.
Improvement:
Should be disregarded:
PROP TEMPO:
Deter: Should be disregarded.
Impr: may be disregarded.
In any Case: Gust may be disregarded.
BECMG: BAD FROM THE START.
GOOD FROM THE END.
TEMPO: LONG LASTING = BAD
SHORT TIME = NOT THAT BAD.
PROP TEMPO: I don't care.
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