On January 26, 2011, the USDA granted the Illinois Department of Agriculture’s request for federal disaster assistance for southern Illinois farmers who suffered crop losses caused by drought in 2010. The 16 counties are for the most part south of Interstate 64. The full press release can be seen here.
Rainfall amounts in parts of southern Illinois were much below normal from May all the way through October. However, the pattern and sequence of rain events varied from month to month and place to place. Therefore it’s hard to make a general statement about all the counties in the declared region. For example, Cairo IL received 28.6″ of rain from April to September (over 6 inches above normal) while Fairfield received only 17.1 inches (over 6 inches below normal).
Two contributing factors to crop losses are the regions shallow soils that hold less water and temperatures that were about 3 degrees above normal.
Here are two maps that show the percent of normal precipitation for the period of April-June 2010 and July-September 2010. As a rule of thumb, any 3-month rainfall totals less than 70% of normal is cause for concern. Click maps to enlarge.
The statewide average temperature for November 2010 was 43.4 degrees, which was 1.6 degrees above normal. That makes it the 26th warmest November since statewide records began in 1895.
By the way, the 2000’s are well represented in the list of warm Novembers. Their rank and year include: #1 (2001), #5 (2009), #10 (2004), #14 (2003), #16 (2005), and #17 (2006).
The statewide average precipitation for November was 3.2 inches, only 0.1 inches below normal. November was exceptionally dry until the long Thanksgiving weekend arrived. Rains from that period signaled the recovery of soil moisture around the state. See the earlier posts on this subject.
The highest monthly total precipitation in Illinois for November was 7.15 inches recorded at Mt Carmel. The highest daily temperature for November was 82 degrees recorded at Cairo on November 13. The lowest daily temperature for November was 12 degrees recorded at Mt Carroll on November 26.
The statewide average temperature for fall (September-November) was 55.4 degrees, 1.2 degrees above normal.
The statewide average precipitation for fall was 8.6 inches, 0.8 inches below normal. Widespread rains in early September and late November masked the long period in between with dry conditions. Note: these numbers are preliminary and subject to change as more data arrives.
Heavy rains over the weekend put a major dent in the drought in southern Illinois and neighboring states. Amounts of two to four and a half inches were common throughout the southern half of the state. Some places saw more rain in the last week than in the last three months. For example, Mt Carmel reported 5.07 inches in the last 7 days while receiving a combined total of only 4.34 inches during the months of August, September, and October.
These widespread rains should give relief to other drought-stricken areas of the Midwest as well, including Missouri, Kentucky, Indiana, and Ohio.
Much needed rain arrived in Illinois over the last few days. As the map below shows, amounts of 0.50 inches or higher occurred across Illinois for the 7-day period ending November 23. And typical to these situations, the area in most need of rain misses out. In this case, that would be far southern Illinois. There is a second opportunity for rain in the next few days.
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.
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