At News5, the Storm Impact Scale, or "SIS" for short, was developed by our station to warn of threatening weather. The Storm Impact Scale goes from 1 to 5, and it all has to do with a storm's strength and its impact on our lives.
Where you'll see these numbers referenced is on the 7 Day Forecast.
Level 1 warns of light snow accumulations, and mostly minor traffic issues. We don't want you to cancel your plans, but encourage you to drive safely to and from work.
Level 2 means snowfall totals of 2 to 4 inches will be possible. Roads could become snow-packed and icy. School delays may occur, and your outdoor plans could be impacted for part of the day.
A level 3 alert is meant to be taken more seriously. This type of storm can make travel difficult and close schools for the day. Snow totals will range between 4 and 8 inches. Plan for some significant travel delays, especially during rush hour traffic.
If a level 4 or level 5 alert is issued, we suggest that you stay put. Level 4 is a major storm and potentially dangerous. Snow totals will range from 8 to 12 inches. Schools and businesses may close and some roads could become impassable.
On the rare occasion that we issue a level 5 alert, we urge you to stay home and remain sheltered. More than a foot of snow is expected. Blizzard conditions may occur at times, with winds over 35 mph and near whiteout conditions. Widespread road closures will happen, stranding drivers where they are for hours or days at a time.
With winter still more than a month away, find your First Alert5 forecast anytime on our website or download our app for news and weather on the go.