<p>It's become as certain as cold Thanksgiving leftovers, Christmas lights and cheap holiday parties with bad booze.</p><p>The legislative onslaught is about to begin.</p><p>As the calendar turns to December, Congress is about to encounter a legislative avalanche, ensuring the next 18 days will be filled with action on issues from education to transportation, from taxes to refugees.</p><p>And as if on cue — and seemingly out of nowhere — Capitol Hill is snapping into action.