I honestly can't ever remember a formal closure for snow west of North Bend in the past 15-20 years, so what she was referring to must have been due to accidents, or just being impractical to make it up the hills to North Bend in the snow storm. Plus unlike the pass, there are alternate routes to get to North Bend like SR 202, so I-90 being closed wouldn't strand her in itself, it seems more like she just didn't want to risk getting stuck (which is probably the right move given how many cars seem to end up abandoned on the side of the road when a snow storm messes up the evening commute here).