Originally Posted by Iccy
There is a legal grey area here.
I'm surprised you'd ask such a question. What's logical, safety-wise? Say even on a short sector, you depart for a place that has an Inter; you're not carrying a "proper" Alternate but have your 30 minutes, just. Half way there, the forecast goes to Fog (or Tempo 95TS). Logic surely says you now do not have the required fuel, and you must go somewhere else to top up (if you can). If you can't, then obviously press-on and become a Mildura statistic, hopefully with a satisfactory outcome, although you wouldn't have a leg to stand on in court if you could have diverted but didn't.
Curtain Twitcher, I would say if the forecast says Tempo, that's what is needed for the weather, nothing more. If you were the only aircraft in the sky, then the extra holding you required constitutes a f-up on BoM's part. If you were being held up by numerous other aircraft, then ATC has stuffed up because they didn't correctly predict the traffic holding.
It's about time the "system" started taking responsibility for the issues brought to light after this almighty stuffup. What would have been the consequences had the DJ 737 landed in the drain, or worse, on the tarmac??