As
bfisk wrote:
Anyways, your company manuals should address this.
We have in our OM-C the following:
If available, the TREND forecast appended to a METAR or SPECI overrules any TAF for the period of validity of the TREND.
TREND - TRENDTYPE LANDING FORECAST
Definition:
A forecast intended to meet requirements of local users and of aircraft within about 1 HR flying time from the AD.
The period of validity is normally 2 HR from the nominal observation time of the report to which the TREND is appended.