Summary: January in Illinois finished out at 26.7 degrees, 0.3 degrees above average. Both precipitation and snowfall were below average. The statewide average precipitation (rain plus water content of snow) was 0.85 inches, 1.22 inches below average. Snowfall was below average across most of the state.
The temperatures in January in Illinois showed some very large swings that tended to cancel each other out in the end since we finished 0.3 degrees above average. The first 9 days were above average, followed by 4 days below average, then 3 days above average. The second half of January started out much below average, but steadily warmed and by the end of the month was 20 degrees above average.
While the magnitude of the swings were impressive, the pattern of warm and cold stretches is typical of winter in Illinois and represents the passage of warm and cold fronts across the region. Because it may take a day or more for a system to pass through Illinois, the dates and size of the temperature departures at a particular station may not correspond to the statewide numbers, especially in far southern Illinois.
The January precipitation (left) and departures from average (right) show that precipitation was uniformly light across Illinois, just under an inch in most places (light green) and just over an inch below average (shades of yellow).
The January snowfall (left) ranged from 2 to 5 inches in most locations. Western Illinois saw 5 to 7.5 inches. However, as the panel on the right indicates most of Illinois received below-average snowfall (shades of beige and yellows).
October ended up warmer and drier than average in Illinois. The statewide average temperature was 55.8 degrees, 1.7 degrees above average.
The statewide average precipitation was 1.47 inches, 1.79 inches below average and the 22nd driest October on record. Even so, there were a few areas on the border with Iowa and Kentucky that received 2 to 3 inches of precipitation (dark blue in map below). The two largest monthly totals came from Stockton IL (COOP) and Orion IL (IL-HY-1), both reporting totals of 3.47 inches of precipitation.
The outlook for November, according to the National Weather Service, shows an increased chance for above-average temperatures across Illinois and the Midwest. The outlook shows an increased for above-average precipitation for the southern two-thirds of Illinois. This is part of broad area of expected wetter conditions across the southern US. Meanwhile, the northern third of Illinois has equal chances (EC) for above, below, and near-average precipitation. Click on the maps to enlarge.
Here is the rainfall map for the past 7 days. Most of the rain in Illinois has come in the last 2 days of that mapping period. In fact, almost all the rain in October for Illinois has fallen in the last 2 days.
Most of Illinois was in the two lighter shades of green, indicating rainfall amount of between 0.5 and 1.5 inches. There is a hole in southwestern Illinois (blue) were rainfall amounts were less than 0.5 inches. Higher amounts of 2 or more inches just missed Illinois, and fell across the border in Kentucky and southern Indiana.
It looks like we have one last shot of rain in October on Saturday.
August was cool across the state and dry in most places in Illinois, capping off a summer that was cool and wet.
The statewide average precipitation for August in Illinois was 2.95 inches, 0.64 inches below average. However, this was followed by a very wet June with 9.44 inches, and a wet July with 4.84 inches. As a result, the summer precipitation total was 17.23 inches. That was 5.36 inches above average and the 6th wettest summer on record.
Here are the top ten wettest summer in Illinois. It was wetter than last summer and 2010, but nearly an inch away from the incredible summer of 1993.
How things are shaping up in 2015? The outstanding features so far are the extremely cold February and the extremely wet conditions in southern Illinois while dry elsewhere.
Monthly Temperature Departures from Average
Blue means colder than average, red means warmer than average. Temperature departures from average tend to cover very large areas, making the statewide average temperature departure a good indicator of conditions around 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.
Last week, the Climate Prediction Center released their outlooks for February and beyond. There is nothing exciting to report for Illinois. Both the outlook for February and the 3-month outlook for February-April have us in “EC” or equal chances of above, below, and near-average temperature and precipitation. See map below (click to enlarge). That’s not bad news – it means there are no increased risks of a colder than average winter. Continue reading “Seasonal Outlooks for Illinois”
Here are the patterns of precipitation and temperature departures across the Corn Belt for October so far. The eastern half of the Corn Belt experienced both wetter and cooler than average conditions for the month. Meanwhile, the western Corn Belt was both drier and warmer than average.
Today the NWS Climate Prediction Center has released their latest outlook for November and this winter. Below are the maps for November temperature, November precipitation, December-February temperature, and December-February precipitation.
For Illinois, November temperatures have equal chances (EC) of being above, below, or near-average. November precipitation is rated as EC except for the northeast quarter of the state, which has an increased chance of below-average precipitation. This is part of a larger area with increased chances of below-average precipitation across the Great Lakes region.
The category of EC is a little hard to interpret. Basically, it means that there are no consistent indications that conditions could be too warm/cold/wet/dry. Sometimes I call it a neutral forecast.
For December-February, the traditional winter months, Illinois has equal chances (EC) of above, below, and near-average temperatures. However, Illinois has an increased chance of below-average precipitation.
The statewide average temperature for October so far in Illinois is 56.5 degrees, 1.4 degrees below average. The statewide average precipitation for October so far is 2.5 inches.
Here is the map showing how the precipitation has fallen in Illinois and surrounding states. The heaviest amounts in Illinois were the 3 to 5 inches between Interstates 70 and 74. Amounts of 1 to 3 inches were common in the northern and southern thirds of the state. The largest total so far is 8.38 inches reported at Greenfield in Greene County