Lucy Weather

Polar Vortex (AO) — strength of the ring of winds around the North Pole. Positive values mean the vortex is locked tight and Arctic air stays bottled up north. Negative values mean a weak, wavy vortex that lets Arctic outbreaks spill south.

Storm Track (NAO) — the North Atlantic pressure seesaw that steers the jet stream. Positive favors a strong jet with milder, wetter weather across the eastern U.S. Negative favors blocking highs, colder eastern U.S., and more European storminess.

Pacific Pattern (PNA) — the ridge-and-trough setup over North America. Positive plants a ridge over the West and a trough over the East (cold eastern U.S.). Negative flips it — active Pacific storm track aiming into the Plains and a milder East.

Values generally run −3 to +3. Anything beyond ±1 is meaningful; ±2 or more is a strong signal. These indices drive weather 1–3 weeks out, which is why we track the trend as well as the current value.

Lucy reads these same numbers and folds them into her broadcast, tailoring the plain-language outlook to our region.