Having been caught with their predictive pants down last week (10+" snow rather than 2), amid the entire country in weather chaos, the Portland Bureau of Transportation just sent out a long email regarding the ongoing Winter Travel Advisory (more snow likely} with this little snippet tucked in about halfway through:

"The public should be prepared for worse conditions than is forecast, including more snow and snowfall that arrives earlier or later than expected."

So, yeah, all bets are off and they hold no credibility . . . !