WBZ AccuWeather iScale

iscale topper 12 14 update WBZ AccuWeather iScale

In New England, we are accustomed to measuring each storm by the amount of snow it will drop, but the true measure of a storm should encompass more than just snowfall amounts, it should measure how the upcoming storm is going to IMPACT you.

The WBZ Weather team has designed the iScale, which will help you plan ahead and be better prepared before the first flakes fly.

The iScale values will differ from region to region, since the forecast can vary across our area. Here are the factors considered:

There is a big difference between snow falling during a commute and snow on the weekends.

Precipitation Type
If you have to clear your own driveway, by shovel or by snowblower, you know that a light fluffy snow is a lot easier to take than a heavy, wet, cement-like snowfall. Just a small amount of ice can also wreak havoc on the roadways and on your front steps.

Snowfall Amounts
The dreaded snowfall accumulation map.

Wind & Power Outages
Typically, wind speeds greater than 35mph are going to cause problems no matter what season you are in, many times leading to power outages as well.

Coastal Flooding
Many times this factor alone can be the difference between a minor event or a major one where life and property are at risk.

There can and will be vast differences in impact within just a few miles, therefore, each community and section of Southern New England will be assessed and placed in an impact category of Low, Moderate, High or Severe. Below are some general guidelines and example scenarios.


Wintry weather is happening, but it will have little effect on your day. An example might be a 1-3” snowfall during the day which is only sticking on grass with surface temperatures slightly above freezing. A very frequent occurrence during winter.


A definite disruption for travel and plans. Not likely a blockbuster storm but something on the magnitude of 6”, perhaps with wind and minor coastal issues as well. Could also indicate some icing. About 5-10 of these type events each winter season.


A major New England winter storm…Could indicate a foot or more of snow, school and business delays and cancellations, powerful and damaging winds, and perhaps some Coastal flooding. Likely only a handful of these events each year.


Life and property threatening event. Only occurs once every few years. A “Blockbuster” type storm, could be in the form of severe icing, well over a foot of snow (widespread) and/or major coastal flooding.