Published: November 20,2015
Winter Storm Bella will bring the first, not to mention locally heavy, accumulating snow of the season for some in the Upper Midwest, Corn Belt, and Great Lakes.
(MORE: Science Behind Naming Winter Storms)
Winter Weather Alerts
Parts of the Sioux City, South Dakota metro area picked up over a foot of snow in an intense snowband Friday. Some of those heavy snowfall rates have since spread across northern Iowa.
(MORE: Bella's Travel Impacts)
Winter storm warnings continue from much of Iowa into northern Illinois and southern Wisconsin, including the Quad Cities, Madison, Rockford, Milwaukee and Chicago.
In the much of the Upper Midwest, this means a likelihood for at least 6 inches of snow in 12 hours, or 8 inches of snow in 24 hours.
Winter weather advisories are posted for much of Lower Michigan and far northern Indiana, including Detroit, Grand Rapids and Lansing, where somewhat lower snowfall totals are expected.
With the cold air in place, another jet-stream level disturbance will intensify as it sweeps eastward over the newly-arrived cold air from the northern Rockies to the Great Lakes and eastern Canada into the weekend.
(FORECAST: Cold Has Returned)
Moisture will be markedly more limited with this system than with Winter Storm Ajax, as well as the severe weather and flooding rain that plagued the Plains and South.
However, the strength of the jet-stream disturbance, forcing a wave of low pressure along the frontal boundary, then strengthening it over the Great Lakes, will still squeeze out a swath of significant snow Friday and Saturday from the Plains to the Great Lakes.
Snowfall Reports
Despite lacking strong surface low pressure, these systems are notorious heavy snow generators in the Midwest.
Snowfall Totals So Far
As of Friday night, several locations in southeastern South Dakota and northern Iowa have reported a foot or more of snow from the storm. The highest reported total was 18 inches at Tea, South Dakota.Here is a sampling of official snowfall totals around the area:
- 7.2 inches: Sioux Falls Airport, South Dakota
- 6.0 inches: National Weather Service, Johnston, Iowa.
- 2.0 inches: Norfolk, Nebraska.
- 0.3 inches: Omaha, Nebraska.
Winter Storm Bella Snow Forecast
Snowfall Forecast
However, a swath of moderate to heavy snow is still expected from southern Wisconsin and northern Illinois to Michigan. Where smaller-scale, more intense snowbands temporarily set up, snowfall rates from 1-2 inches per hour can be expected, for a time.
These are the areas where at least 6 inches of snow is most likely through Saturday. Some of the highest snow totals will exceed one foot.
Warm ground from what had been an exceptionally warm first half of November may take a small cut from total accumulations of snow, particularly on pavement. Also, while winds off Lake Michigan will contribute low-level moisture to the storm, relatively warm lake temperatures may also mitigate snowfall totals a bit near the lakeshore.
However, heavier snowfall rates may overcome these warming factors near the lakeshore, if they occur.
Surface low pressure is expected to strengthen a bit once it reaches the Great Lakes, thanks to the intensifying jet stream disturbance.
The pressure gradient between this developing low and high pressure building in the Rockies and High Plains will produce increasing winds in the snow area Friday night and Saturday, leading to some reduced visibilities in blowing snow, and some minor drifting, but we are not anticipating blizzard conditions with Winter Storm Bella.
Once the surface low wraps up in eastern Canada, some bands of lake-effect snow are possible off Lakes Ontario and Erie, and a little wrap-around snow may blanket the Allegheny Plateau, Appalachians, Adirondacks and high country of northern New England.
Given this first snow of the season in some of these areas may be locally heavy, slow down, leave extra time if you must travel, or consider postponing your trip.
Latest Winter Weather Radar
Flight delays are probable Saturday out of Chicago-O'Hare Airport, and are possible out of smaller regional airports, as well. Check your flight status before leaving for the airport.
(MORE: Average First Snow Dates | Snow & El Niño)
Winter Storm Bella Snow Timing
Through Daybreak
Snow will gradually taper off across eastern Iowa. Further east, snow continues across southern Wisconsin and northern Illinois. Snow becomes heavy at times across Chicagoland and some light snow showers may affect areas as far south as northern Missouri.Some blowing and minor drifting snow is possible across portions of Iowa.
Season's first accumulating snow cities: Milwaukee, Chicago
Saturday
Saturday's Forecast
Snow will end by midday in eastern Iowa and northern Missouri.
Any rain may change to snow in northern Ohio, northwestern Pennsylvania and western New York Saturday night.
Increasing winds Saturday night may produce areas of reduced visibility in Michigan, and all the Great Lake snowbelts with the exception of the Lake Ontario snowbelt.
Season's first accumulating snow cities:
- Saturday: Chicago, Grand Rapids, South Bend, Detroit
- Saturday night: Erie, Pennsylvania
Sunday
Sunday's Forecast
A few snow showers are possible across northern New England, although moisture appears to be relatively limited.
Gusty winds may persist around the eastern Great Lakes and New England.
A few flakes may even fly across the central Appalachians from West Virginia into interior Pennsylvania, though little to no accumulation is anticipated.
(MORE: Winter Storm Central)
Check back with us at weather.com and The Weather Channel for updates and the latest forecast of Winter Storm Bella.
November Heavy Snow: It's Been Awhile For Some
Despite the Upper Midwest's snowy reputation, heavy snow in November outside the Great Lakes snowbelts isn't as common as you might think.According to National Weather Service data, Chicago hasn't seen a November with 6 inches or more of snow since 1978, much less 6 inches of snow in one November storm.
Average November snow in the Windy City is only 1.4 inches, just under 4 percent of their average seasonal snow. Their average date of the season's first 1 inch-plus snow is December 7.
Last season, it took the Windy City until January 5 to accumulate a season total of 6 inches, which they may do so with Bella here in late November. In fact, their first 6-inch-plus snow event of last season was Winter Storm Linus just before Groundhog Day.
Similarly, Milwaukee hasn't seen a 6-inch-plus November snow total in 20 years. In terms of snowfall so early in the season, Milwaukee has only recorded four 2-day snowfall totals of greater than 6 inches before Nov. 22, dating back to the late 1800s.
Five of the past nine Novembers in the Brew City haven't even produced one-half inch of snow, total.
Across the lake, however, Grand Rapids, Michigan, has had a break so far this November, lacking measurable snow prior to this weekend system. November 2014 was their record snowiest November, with 31 inches of snow during the month.
(MORE: Winter 2015-2016 Outlook)
Also of interest is the tendency for less snowy seasons during strong El Niños, which we are currently in.
In five previous strong El Niño seasons (1997-98, 1982-83, 1972-73, 1965-66, 1957-58), Chicago has picked up an average of only 23 inches of seasonal snow, which is 15.4 inches below the 1950-2015 average of 38.4 inches.
(MORE: Snow & El Niño)
Jonathan Erdman is a senior meteorologist at weather.com and has been an incurable weather geek since a tornado narrowly missed his childhood home in Wisconsin at age 7. Follow him on Twitter and Google Plus.
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