All those flakes add up to Chicago’s fifth-snowiest winter
BY HANNAH LUTZ AND ROSALIND ROSSI Sun-Times Media February 17, 2014 3:41PM
- Interactive graphic: Chicago's wet, cold and snowy numbers
- Winter seasons with the most subzero lows
- Video: Forecast updates from ABC7
Updated: March 19, 2014 6:18AM
Monday’s snowstorm pushed this season into the record books as Chicago’s fifth-snowiest winter.
And in the latest tweak from Mother Nature, downtown Chicago experienced “thundersnow” Monday.
Thunder crackled and lightning flashed as snow fell at Navy Pier about 3 p.m., at the beginning of an especially challenging evening rush hour, according to the National Weather Service.
“It’s pretty uncommon,” said Eric Lenning, a weather service meteorologist.
Quick-falling, heavy snow reduced visibility to as little as an eighth of a mile in some areas and turned roadways slushy and slick. At 10 p.m., some parts of the Kennedy still had a thin coating of snow.
By 11 p.m., O’Hare had recorded 5 inches of snow for the day, bringing the season’s total to 67.9 inches. That pushed this season past the winter of 1951-1952 for the fifth-snowiest on record, Lenning said. The next target: the winter of 1966-67, which saw 68.4 inches. Other parts of the Chicago area saw as much as 7 inches, according to the weather service.
More than 820 flights were canceled at O’Hare and 270 were scratched at Midway as snow fell at a rate of 2 to 3 inches an hour.
Temperatures expected to rise above freezing on Tuesday and Wednesday, with highs in the upper 30s. Then they’ll dip back down overnight, with lows in the upper 20s.
That should create an “ideal melting situation,’’ meteorologist Jamie Enderlen said — and that could cause flooding.
On Thursday, temperatures could jump to a high of 43 and rain showers are expected.
“The big question mark” is how much the rain will melt the snow and how much of the rain will be absorbed by the snow, Lenning said.
Snow already on the ground contains 1 to 4 inches of water, with the highest totals near the Wisconsin state line. The melting snow and rain may have no place to go because the moisture can’t soak into the frozen ground, according to the weather service. Instead, water will flow into rivers, and that might cause runoffs and flooding.
Rivers will start to rise when the snow melt and runoff stream into them. There is also a risk for an ice jam, which starts when ice breaks into blocks that collide with each other. Ice jamming can lead to significant increases in water levels and flooding, according to the weather service.
The weather service hasn’t issued a flood warning yet, but meteorologists are monitoring updates from the river forecast center.
City workers have cleared catch basins — openings on the sides of streets that drain excess water — to prevent flooding and give water a place to filter. If litter settles in a catch basin, water can’t reach the sewer.
Department of Water Management spokesman Tom LaPorte suggests that Chicago residents help drainage by raking litter out of basins near their homes so that water can flow into sewers.
“Rainblockers,” which keep water in the streets and gradually send it to sewers, are also part of catch basins on many Chicago streets, LaPorte said.
During a rainy season, rainblockers help water enter sewers, but trash clogging the blockers delays drainage. If water is in the street for a few hours, the rainblocker is probably working properly, LaPorte said. If the street is flooded with water for more than a few hours though, LaPorte suggests calling 311.