Above is the storm total accumulations from a big snow storm that hit St. Louis a year ago, March 3rd and 4th 2008. In fact, the 10" of snow at Lambert International Airport made this storm tied for the 3rd heaviest snowfall in March in St. Louis history. Thanks to the weather service for putting together this complicated map, because it shows some interesting details.
First of all, notice the main heavy snow band that cuts through the St. Louis area. That's a 6-9" or more area of snowfall. So, the metro took the brunt of this snow storm.
Then, notice the sharp drop off in snowfall as you go West or East of that main heavy snow band. For instance, some parts of Western St. Louis County had 12" or more of snowfall. But if you were to travel only about 5 to 10 miles to the Northwest into St. Charles County, the snowfall totals were 3 inches or less! And if you went into Illinois, you would encounter not only lesser snowfall totals than St. Louis, but ice and sleet too.
This is a classic example of snow banding. Relatively thin bands or strips of heavy snow will develop within a snow storm. These bands produce intense snowfall, sometimes with thundersnow and snow rates of 2" or more an hour. You see these bands a lot with lake effect snow, though in our case no body of water was a major influence. Instead, it was almost how a spring storm system will develop isolated intense thunderstorms. In this case, it's an isolated intense band of snow.
The guys and gals at the weather service put together a great web page to archive this storm event, click here for the link.
Meteorologist Steve TempletonView image