Monthly Archives: December 2010

Record December Snowfall: Champaign-Urbana

Champaign-Urbana set a record for their heaviest December snowfall total on record. The 20.4 inches of snow that has fallen so far in December surpassed the old record of 19.1 inches set in 1983.

The 5.0 inches of snow on Christmas Day clinched the December snowfall record. By the way, it was also the biggest snowfall on record for that date. It surpassed the old record of 3.8 inches that fell on December 25, 1944.

We have had measurable snow on the ground since December 4.

It has been persistently cold as well. The average temperature for December through the 27 is 21.3 degrees, the ninth coldest December on record. The forecast is for milder temperatures for the rest of the month so this December may slip a little in the rankings. Oddly, we only dropped below zero once, on December 9 with -1°F.

A complete listing of Champaign-Urbana observations are found  here.

What happened to the rest of the 1983-84 winter? The snowfall total for January was  only 5.6 inches. However, the heavy snow returned in February with 11.6 inches and 8.4 inches in March. Combined with the 0.2 inches that fell in November 1983, that winter season ended up with 44.9 inches.

Update on Cold Weather in Illinois

As of December 21, Illinois remains 10.2 degrees below normal for the month. At 20.9 degrees, this is now the 5th coldest December since statewide records began in 1895. It could still move up or down in the ranking, depending on how the rest of December behaves.

Statewide precipitation stands at 1.06 inches of precipitation (rainfall plus the water equivalent of any snow).

Snowfall totals for the month ranges from less than 2 inches in far southern Illinois to over 14 inches in northwest Illinois (see map below). Right now the two spots with the most snowfall in the state for December are a CoCoRaHS site near Marseilles with 18.5 inches and a CoCoRaHS site near Champaign with 18.3 inches of snow.

From my web page on current conditions in Illinois, here is the breakdown by region within the state as well as the statewide numbers at the bottom for December 1-21.

                        12/01/2010 to 12/21/2010

Climate          <------Temperature----->   <---------Precipitation--------->
Division         Actual   Normal      Dev   Actual   Normal     Dev   Percent
Northwest          15.2     26.3    -11.0     1.44     1.45    -0.01       99
Northeast          17.0     27.9    -10.9     1.30     1.63    -0.33       80
West               21.4     29.7     -8.3     0.56     1.63    -1.07       34
Central            18.9     29.7    -10.8     1.13     1.76    -0.63       64
East               17.6     30.1    -12.4     1.53     1.75    -0.23       87
West-southwest     23.8     32.5     -8.6     0.56     1.91    -1.35       29
East-southeast     23.3     33.6    -10.2     1.23     2.04    -0.80       61
Southwest          26.2     35.7     -9.5     0.79     2.31    -1.52       34
Southeast          26.4     36.4    -10.0     0.93     2.43    -1.50       38

State              20.9     31.1    -10.2     1.06     1.86    -0.79       57

Dev means Deviation From Normal, Percent means Percent of Normal
December snowfall in Illinois

Snowfall for Illinois for December 1-21, 2010.

Champaign-Urbana December Snowfall

The December 2010 snowfall in Champaign-Urbana is at 15.4 inches as of the morning of December 21. That makes it the 7th snowiest December on record.

  1. 19.1″ in 1983
  2. 18.5″ in 1981
  3. 18.1″ in 1973
  4. 18.0″ in 1909
  5. 17.4″ in 1977
  6. 15.7″ in 1950
  7. 15.4″ in 2010 (as of December 21)
  8. 14.7″ in 2000
  9. 14.0″ in 1990
  10. 13.3″ in 1915

Looking at the NWS forecast, we can still move up the ranks. Given the 6 inches of snow on the ground in C-U, the forecast for cold temperatures to persist, and the chance of snow on Christmas Eve means we have a very good chance of a white Christmas.

Revised Winter Forecast

NOAA’s Climate Prediction Center has revised their winter forecast today. Their earlier outlook for December-February called for increased chances of above normal temperatures in the southern two-thirds of Illinois and above normal precipitation for all of Illinois.

However, December is already shaping up to be on the cold and dry side (see earlier post).

Now their outlook for January calls for equal chances of above, below, and near-normal temperature and precipitation in Illinois. It’s what I call a neutral forecast.

In their forecast for January-March, they call for an increased chance of above-normal precipitation in Illinois as well as much of the Ohio River Valley and Great Lakes region (see map below). Their temperature outlook remains neutral for Illinois for this period.

NOAA precipitation outlook for January-March

NOAA's Climate Prediction Center precipitation outlook for January-March.

Cold Start to December

After such nice weather in October and most of November, real winter weather arrived in Illinois for December. The statewide average temperature for the first 14 days of December was 22.0 degrees, 10.6 degrees below normal.

The statewide average precipitation is 0.83 inches, 0.5 inches below normal.

Snowfall has been widespread across the state in early December. Snowfall totals range from less than an inch in far southern Illinois to over 10 inches in northwestern Illinois. See map below for snowfall totals for December 1-14, 2010.

December 1-14, 2010 snowfall.

Snowfall for December 1-14, 2010, for Illinois.