Notwithstanding instructions in company operations manuals it's interesting to note that in the UK ANO under pre flight action of the commander of an aircraft that he/she shall obtain weather before flight that is "reasonably practical to obtain".
I know this is another part of the world but it would be interesting to see what ICAO says on this.
Sometimes you cannot get certain elements of weather before flight. It has been stated earlier in this thread that at the time of day of crew report the met services were often unavailable. In this day and age there are many other online ways of getting weather information many if which are better than some facilities at certain airports.
With respect to the Sig Weather charts it's interesting to look up the definitions of Isolated and Occasional - the former is up to 25% coverage and can "EASILY" be avoided, the latter 50% and can be avoided. On that basis a planned flight through those areas seems quite reasonable to me.
Last edited by fireflybob; 5th Jan 2015 at 08:11.