Northern Lights Webcams
A simple search online will bring up a lot of aurora webcams. The webcams I use the most to see northern lights are:
Using webcams to see the skies is the easiest way of knowing a storm has hit. Looking at the numbers and information on websites is very useful. But a lot of warnings rely on KP level.
Although the KP level is a good identifier if a minor storm KP2 has high density, good windspeed 600+ and a strong negative BZ it is possible to see them in Southern Finland.
Find your own? Good searches are:
Northern Lights webcams list
Aurora Borealis webcam live
Other searches I would recommend is the country you are visiting or living in. eg: Finland Northern Lights webcams OR suomi revontulet webcam
Some more Links (including Webcams) can be found here