School districts around the Portland metro area are keeping a wary eye on weather forecasts, with possible freezing rain, ice and even a little more snow on Tuesday, when classes are supposed to resume after the holiday weekend. For Portland Public Schools, the decision whether to cancel classes when snow or ice is forecast is especially fraught this year. A district spokesperson said Sunday that decision-makers would meet on Monday afternoon to review forecasts for the following day. That’s because the district has virtually no wiggle room left in its calendar, after the prolonged teachers’ strike in November ate up 11 instructional days plus a late start morning. To make up for those lost hours, Portland students are already scheduled to attend school during what would otherwise be the days set aside for make-up instruction in the event of snow — June 12, June 13 and June 14. That leaves the district in a pickle. Even though much of the Portland area received relatively low amoun...