The Washington region’s big dig out from under this weekend’s historic snowstorm seemingly progressed well Monday as temperatures neared 40 degrees and many commuters stayed off the roads, easing the way for plows to get into the neighborhoods.

Despite some progress, many challenges remained. Side streets were partly snow covered and bumpy from new potholes. Travelers stranded by the unprecedented December nor’easter that dumped 16.6 inches at Ronald Reagan Washington National Airport, and up to 2 feet elsewhere, struggled to escape the region. And melted snow was expected to refreeze overnight.