This was the 5th warmest November on record for Illinois, based on preliminary data. The statewide average temperature was 47.4 degrees, and 4.9 degrees above normal. Here are the top ten warmest Novembers in Illinois since 1895:
2001 with 49.9°F
1931 with 49.1°F
1909 with 48.8°F
1999 with 48.4°F
2016 with 47.4°F
2009 with 47.2°F
1902 with 46.9°F
1990 with 46.8°F
2015 with 46.6°F
1913 with 46.4°F
It was also the 2nd warmest fall on record for Illinois. The statewide average temperature for fall was 59.4 degrees, 5 degrees above normal. Only the fall of 1931 was warmer at 59.8 degrees. The climatological fall months are September, October, and November.
Summary: Illinois just finished its third wettest and tenth warmest November on record. Even with the warmer conditions, significant snowfall fell across the northern half of the state over the weekend before Thanksgiving.
The statewide precipitation total was 5.60 inches, 2.13 inches above average and the third wettest November on record. In first place was 1985 with 9.05 inches, and in second place was 1992 with 6.51 inches. I remember November 1985 quite well – it was overcast every day and dreary the entire month.
The largest reported precipitation total for November was Rock Island Lock and Dam with 8.39 inches. This was followed closely by Sparta (IL-RH-8) with 8.09 inches. Precipitation includes both rainfall and the water content of snowfall.
Here is the map of total precipitation for November. Areas in yellow and orange received 6 to 9 inches of precipitation. Areas in the shades of green were not quite as wet but received between 3 and 6 inches of precipitation.
A large, slow-moving low-pressure system passed through the central US this week, bringing widespread rains from Louisiana all the way up the Mississippi River Valley. Areas in yellow and beige received 2 to 4 inches of rain, including large parts of Illinois. Some counties along the Illinois-Indiana border received amounts in the 1 to 2 inch range. Meanwhile, areas in Missouri and Arkansas received 5 to 8 inches.
The largest amount reported in Illinois in the last three days was 3.95 inches in White Hall, IL. White Hall is in Greene County and where my great-grandparents lived.
Here are the rainfall departures for November so far. Areas in green are between half an inch and two inches above average. Areas in blue are two to four inches above average. This should pretty much erase any concerns about dry conditions earlier this fall.
By the way, these maps came from a NWS product at http://water.weather.gov/precip/
It has been a very cold week in the US with temperature departures in the central US at 15 to 25 degrees below average. Yesterday, Champaign-Urbana was 26 degrees below average for the date and just 2 degrees shy of the record low of 6 degrees set back in 1891.
Here is the temperature departure for today from the site Climate Reanalyzer showing the bitterly cold temperatures in the eastern half of the US, while once again Alaska is well above average. We saw this pattern most of last winter, starting in late November.
Here is the plot of the jet stream (high winds at upper levels of the atmosphere – shaded in yellow and red) showing its dip down into the southern US. That means we pretty much have an open door to cold Arctic air in the Midwest.
So far, November has been cooler than average across Illinois and the eastern two-thirds of the Midwest (below). The statewide average temperature is about 5 degrees below average.
The NWS forecasts indicate that temperatures are likely to stay below-average for the next two weeks across Illinois and the Midwest. The second and third maps are the latest NWS 6-10 and 8-14 day forecasts.
The statewide average precipitation for November was only 1.26 inches. That is 36 percent of normal or 2.21 inches below normal. It ranks as the 17th driest November on record since 1895. The maps below show the distribution around the state and how it compares to normal (1981-2010 average).
The statewide average precipitation from January to November was only 27.6, nearly 10 inches below the normal of 37.5 inches. What does this mean for the drought? The recovery that began in late August and through October in much of the state has stalled out.
The statewide average temperature for November was 40.8 degrees, 1.1 degrees below normal.
November was an interesting month in Illinois. The four outstanding features were:
the sixth wettest November on record with a statewide average precipitation amount of 5.23 inches, 1.9 inches above average; several sites in southern Illinois had over 9 inches of rain, including Cairo with 9.92 inches (the most of any site in the state);
the end of drought for western and central Illinois as a result of the above average rainfall in November;
the ninth warmest November on record with a statewide average temperature of 45.3 degrees, 3.6 degrees above average;
the snowiest spot in the state was in far southern Illinois, 2.5 inches of snow fell by the morning of November 30 at Grand Chain Dam on the Ohio River. A few sites in northern Illinois reported an inch or less of snow. As was noted in an earlier post, the “normal” snowfall for November ranges from 1 to 2 inches in northern Illinois to no snowfall in southern Illinois – the near opposite of this year. It is just another example of Illinois weather “not playing by the rules.”
Statewide records of temperature and precipitation go back to 1895. Here are the precipitation and snowfall maps for November.
Based on preliminary numbers, the statewide average precipitation for the first 15 days of November in Illinois was 2.8 inches. That is 1.2 inches above average or 171 percent of average. The largest rainfall totals were in western Illinois, four to nearly five inches in some places, where it was most needed.
Soil moisture readings from Water Survey sites at Perry, Monmouth, Peoria, and Springfield, show that the water content in the top 20 inches of the soil is at 30-35 percent, nearly ideal for this time of year. That is a big improvement over this summer when the water content was only 15-20 percent in the top 20 inches.
With 97 percent of the corn and 98 percent of the soybeans harvested and winter wheat in good shape, many of the agricultural impacts of the 2011 “flash” drought in western and central Illinois are done. The recent precipitation and the precipitation in the next few months should leave Illinois soils fully recharged for spring.
The statewide average temperature for the first 15 days of November in Illinois was 49.2 degrees. That is 4.8 degrees above average.
We have generated maps of the new 1981-2010 normals for Illinois, including the new November snowfall normals and the number of days with “measurable” snowfall (0.1 inches or more). See the maps below (click to enlarge).
While we may sometimes see snow in late October, November is normally the start to the snowfall season for much of Illinois. However, the average amounts are small by the standard of later winter months, ranging from 1-2 inches in northern Illinois to less than an inch in central Illinois to zero in southeastern Illinois.
The number of days with measurable snowfall, or snowfall frequency, is uncannily like the snowfall totals. The snowfall frequency ranges from 1-2 days for November in northern Illinois, to less than a day in central Illinois, to zero in southeastern Illinois. When the frequency drops below one day it means snowfall does not occur every year. For example, an average frequency of 0.5 days means it happens only once every 2 years on average.
The NWS Climate Prediction Center has released their outlooks for October and October-December. For Illinois there is an increased chance that temperatures will be above-average in both the October and October-December time frames. Also there is an increased chance that precipitation will be below-average in both October and October-December.
As posted earlier, this forecast is consistent with the known impacts of the rejuvenated La Niña event occurring in the Pacific Basin. La Niña tends to give us warmer and drier than average conditions in fall. Last fall was a classic example of this with temperatures 1.2 degrees above average and precipitation 12% below average.