A look at what factors will impact this winter's weather

With the first heavy snow of the season on the national weather map, the calendar is quickly careening toward meteorological winter - a season that could prove complex to forecast.

In addition to a potentially fluctuating El Niño–Southern Oscillation , a significant marine heat wave across the northern Pacific and climate change could all play a role, alongside the usual disruptions of the polar vortex.

In its early seasonal outlooks, NOAA called for above-average temperatures along the southern tier of the country, as well as the East Coast.

Much of the nation’s heartland is expected to experience near-normal conditions, while the Pacific Northwest could trend below average.

On the precipitation front, the Northern Rockies and Ohio Valley stand out as regions with the highest chances