[Edited on October 26 to reflect update] Based on data through October 25, the statewide average temperature for Illinois in October is 60.7 degrees. That is 6.3 degrees above normal and the fourth warmest October on record. Temperatures for the rest of October are expected to be 3 to 5 degrees above normal. Therefore, this October could slip in the polls. Here are the top ten warmest Octobers
1963 with 63.6°F
1947 with 62.2°F
1971 with 61.3°F
2016 with 60.7°F
1900 with 60.6°F
1956 with 60.2°F
2007 with 59.9°F
1897 with 59.7°F
1950 with 59.3°F
1920 with 59.2°F
Here are the U.S. temperature departures for October so far . Illinois and the eastern two-thirds of the U.S. are experiencing above-normal temperatures (shown in various shades of pumpkin spice, appropriately enough). Speaking of pumpkins, the harvest for this year looks much better than last year.
October has been both warmer and drier than average so far for Illinois.
Temperatures have run 1 to 2 degrees above average in Illinois and across most of the Midwest (first map). This follows close on the heels of a September that is now considered the 8th warmest on record at 70.4 degrees according to NCEI.
Meanwhile, precipitation has been largely missing in action in October (map below). The areas in gray across Iowa, and parts of surrounding states indicate almost no measurable precipitation has fallen. It’s hard to tell on this map because of the scale, but most of Illinois has received less a tenth of an inch for the month so far. The statewide average is 0.05 inches. Continue reading “October Warm and Dry So Far in Illinois”
While there were a few cold stretches in April, the statewide average temperature for the month was 54.1 degrees, 1.7 degrees above average.
Precipitation in Illinois for April was more complicated. April precipitation was in the range of two to four inches in northern and central Illinois, and 4 to 7 inches in southern Illinois. As a result, the northern two-thirds of the state was slightly below average while the southern third was up to 2 inches above average. Fort Massac State Park reported the highest monthly precipitation total of 7.80 inches.
A glance at the forecast for Memorial Weekend shows near record-breaking temperatures in Illinois. Already the statewide average temperature for May 1-22 is 66.1 degrees, and 3.7 degrees above average. It is now in 19th place as far as the warmest May on record. We will see how that changes over the weekend and into next week.
Monthly Temperatures Since 2011
Below are the temperature departures in Illinois since the beginning of 2011. The statewide average temperature in every month in 2012 has been above average in Illinois. As a result, we are now at 48.4 degrees for the period of January – May 22. That makes this January-May the warmest on record. It beats second place by a full 1.1 degrees (47.3 degrees set in 1921). Statewide records go back to 1895. By the way, the summer of 1921 was about 3 degrees above average with average precipitation.
The streak of warmer than average temperatures extends back to October 2011. Also, eight of the 12 months in 2011 had above average temperatures.
NOAA’s Climate Prediction Center has come out with a new forecast for December and for December-February (winter). This is part of their routine update cycle.
The outlook for December in Illinois calls for an increased chance of above normal temperatures. An increased chance of above normal temperatures translates into just a few degrees above normal. Temperatures in Illinois have run an average of 2.9 degrees above normal for every month since March of this year. Therefore, continuing with a forecast for above-normal temperatures is not surprising.
The outlook calls for equal chances of above, below, or near-normal precipitation (or equal chances as they call it) in December in Illinois.
The outlook for December-February remains the same as last month. There is an increased chance of above-normal precipitation for all of Illinois. And, there is an increased chance of above-normal temperatures for the southern two-thirds of the state. See the figure below for more details.
The first half of November in Illinois has been warm and dry, according to preliminary data from November 1-15, 2010. The statewide average temperature was 47.3 degrees, 2.9 degrees above normal. The statewide average precipitation was only 0.21 inches, only 13 percent of normal for the first half of November.
Past November’s in Illinois
The driest November on record was 1904 with 0.28 inches.
November 2007 was the 25th driest with 1.75 inches.
November 2008 was the 20th driest with 1.48 inches.
November 2009 was near-normal with 2.47 inches.
Normal state-wide precipitation for November is 3.34 inches.
The term “normal” refers to the 1971-2000 average.
For Illinois, the statewide average rainfall for October was 1.4 inches, 1.5 inches below normal or 48 percent of normal. This ranks as the 20th driest October on record. The largest monthly rainfall total was reported at Belvidere with 3.94 inches. See map below for rainfall departures across the state.
While northern Illinois was close to normal on rainfall in October, parts of southern and eastern Illinois remained dry. The U.S. Drought Monitor lists those areas as “abnormally dry” and southeastern Illinois as”moderate drought”. At this time of year, the main impacts on agriculture would be on pasture conditions and winter wheat.
With the vegetation preparing for a long winter’s nap and lower temperatures, the demands on soil moisture are close to zero. So soil moisture should start to recover in the next few months even if precipitation remains below normal. The Illinois State Water Survey posts their latest soil moisture survey a few days after the end of the month here.
The statewide average temperature for October was 56.2 degrees, 1.6 degrees above normal. The highest temperature for the month was reported at Fairfield with 93 degrees on October 10. The lowest temperature for the month was reported at Minonk with 22 degrees on October 29 and Sidell with 22 degrees on October 30.
During October, nearly all of Illinois has experienced temperatures down to 32 degrees and many areas have reached 28 degrees or less. See map below.
So far, October in Illinois has been both warmer and drier than normal. As of October 19, the statewide average temperature was 59.8 degrees, 1 degree warmer than normal. The statewide average rainfall was only 0.22 inches, 12 percent of normal. See table below.
If this were July, the dryness would be a major source of concern. However, the impacts are much less in fall. In fact, the warm, dry weather aided in the maturing and harvesting of corn and soybeans. At the moment, the impacts are mostly focused on:
winter wheat – farmers are waiting on rains for germination;
landscaping – trees and shrubs may need more water before winter arrives;
fall color – I’ve noticed that the fall colors on trees and shrubs this year are muted with lots of shades of brown and yellow.
The NWS forecast shows a weather system moving through Illinois over the weekend. The potential rainfall amounts from this system range from 0.25 inches along the Wabash River in south-eastern Illinois to 1.25 inches in north-central Illinois. Another system is expected to move into the region on Tuesday/Wednesday. So the current dry weather may be short-lived.
10/01/2010 to 10/19/2010
Climate <------Temperature-----> <---------Precipitation--------->
Division Actual Normal Dev Actual Normal Dev Percent
Northwest 55.2 53.4 1.9 0.09 1.82 -1.73 5
Northeast 55.8 53.7 2.0 0.27 1.82 -1.56 15
West 57.6 56.3 1.4 0.10 1.90 -1.80 5
Central 56.7 55.7 1.0 0.22 1.86 -1.64 12
East 56.0 55.4 0.6 0.38 1.86 -1.48 20
West-southwest 58.0 57.5 0.5 0.13 1.72 -1.60 7
East-southeast 58.4 57.8 0.6 0.28 1.92 -1.65 14
Southwest 58.9 58.9 0.0 0.23 1.85 -1.63 12
Southeast 59.8 59.2 0.6 0.35 1.84 -1.49 19
State 57.3 56.3 1.0 0.22 1.84 -1.62 12
Dev means Deviation From Normal, Percent means Percent of Normal
NOAA’s Climate Prediction Center issued new outlooks today for October and beyond. The latest outlook for October shows all of Illinois having increased chances of being both warmer and drier than normal.
BTW, this is the exact opposite of how last October turned out. The statewide precipitation total in October 2009 was 8.40 inches. That was 5.5 inches above normal and the 2nd wettest October on record. The statewide average temperature was 49.6 degrees. That was 4.6 degrees below normal and the 6th coldest on record.
The outlook for October-December shows all of Illinois having an increased chance of warmer than normal conditions. Precipitation has “equal chances” of being above, below, and near-normal, or what I call a neutral forecast.
This summer was one of the warmest and wettest in Illinois history, based on preliminary data. The average statewide temperature for this summer (June-August) was 76.4 degrees, 2.7 degrees above normal and the seventh warmest summer on record. The average statewide rainfall was 16.7 inches, 5.2 inches above normal and the sixth wettest summer on record. Statewide records for Illinois extend back to 1895.
The average statewide temperature for August was 76.8 degrees, 3.2 degrees above normal. That puts it at the 13th warmest August on record. August was on track to being even warmer but a late-month cool spell knocked it down a few notches in the ranking. August rainfall has been close to normal with a statewide average of 3.4 inches, just 0.3 inches below normal.
[This is an update of a post earlier in August, now removed to avoid confusion]