Category: Snow

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First Half of May in Illinois – Warm, Wet, And Then Snow

According to preliminary records, the first half of May was both warmer and wetter than average for many locations in Illinois. The statewide average temperature was 61.2 degrees, about 1.4 degrees above average. Meanwhile, this morning there are reports of snow falling in northern Illinois. Talk about weather extremes. This was after last weekend when we saw widespread reports of highs in the upper 80s and low 90s.

The statewide average precipitation was 2.43 inches, 18 percent above average. Here is a screenshot of the last 14 days showing the widespread and heavy rainfall in much of the northeast, east-central, and southern parts of Illinois with many sites reporting between 3 to 6 inches of rain. Parts of western and central Illinois have not been as wet with amounts in the range of 1 to 3 inches of rain.
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Snow in May? Read more on the Chicago NWS page. It looks like Rockford set a new record for the latest report of snowfall in the season. The Chicago record still stands at June 2, 1910.

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Map courtesy of the Chicago NWS office.
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First Half of February – Cold and Snowy

It is Valentine’s Day. It is also halfway through February. The statewide average temperature so far in February is 11.5 degrees, 14 degrees below the long-term average.

The accumulated snowfall for February 1-14, 2014, ranges from 4 to 5 inches in far southern Illinois to and from 5 to 15 inches in the rest of the state. The band of heaviest snow extends from Quincy to Chicago with amounts of 12 to 15 inches.

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The long-term average (1981-2010) February snowfall is presented in this map below. Comparing it with what snow has fallen so far shows that many places have already exceeded their February average by more than double.

Click to enlarge. Illinois State Climatologist Office. ISWS.
Click to enlarge. Illinois State Climatologist Office. ISWS.

Right now almost all of Illinois is covered in snow, as shown by this image from the National Operational Hydrologic Remote Sensing Center. Southern Illinois is covered by 1 to 4 inches of snow, central Illinois by 4 to 10 inches, and northern Illinois by 10 to 20 inches.

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Click to enlarge. NWS National Operational Hydrologic Remote Sensing Center.

The water content of that snow pack is substantial in the northern half of the state with amounts of 1 to 4 inches (first map below) with higher amounts in states to the north, and upstream, of Illinois (second map). According to the National Weather Service, temperature are expected to be much warmer in the coming week with highs across the state above freezing from Monday through Thursday along with the possibility of rain. It is possible that the snow pack will be greatly reduced by the end of the week and likely gone for many areas in the southern and central Illinois.

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Click to enlarge. NWS National Operational Hydrologic Remote Sensing Center.

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First Major Snow for Some in Illinois

The recent winter storm dropped snow across western and northern Illinois. The first figure is a screenshot of a product found at http://www.srh.noaa.gov/ridge2/snow/
The Davenport, IA, NWS office provided a map with more detail on the heaviest snowfall amounts in northwestern Illinois (second figure). The heaviest snow in Illinois was 11 inches at Apple River Canyon in far northwestern Illinois.

Snowfall map for the period ending on the morning of December 21, 2012. Click to enlarge.
Snowfall map for the period ending on the morning of December 21, 2012. Click to enlarge.

Snowfall map for December 21, 2012, produced by the NWS office in Davenport, IA. Click to enlarge.
Snowfall map for December 21, 2012, produced by the NWS office in Davenport, IA. Click to enlarge.