NOAA has a
Space Weather Prediction Center. On that site (scroll down one screen) is a Aurora forecast overlaid on a satellite view of the northern polar area showing the forecast for the next 24 hr as a video. Click play and it will show the probability of seeing an aurora as a video loop for those parts of the globe.
How far south from the geomagnetic pole you can see the aurora depend the amount of energy in a solar "storm", which is correlated with sun spot activity and the solar cycle. Reported as Kp value on the
NOAA site. For more information about Kp and aurora, and how it effects viewing check out the
NOAA tips on viewing aurora page. Also on that page is an
Image Map for North America that shows relation of Kp and geomagnetic latitude and aurora visibility. Other maps of either hemisphere and alternate views can be found there as well. Since they moved the map from an older website it is no longer interactive.
Really impressive aurora display over Montreal in the PBS NOVA video
Edge of Space starting at 50:06 minutes
Other Products on the NOAA space weather site are:
27 day forecast of KpAurora 3 day ForecastAurora - 30 minute forecast (every 30 minutes for the next 24 hrs)
Space Weather Enthusiast Dashboard