Chicago’s cool spring redeemed itself Sunday by delivering to the city its warmest Easter in nearly 30 years, matching the 79-degree high logged on March 30, 1986. Areas west and south of the city topped 80 and even lakeshore communities reached 70 before cooling afternoon lake breezes set in. Another round of 70s is expected Monday, but a gathering overcast leading to periods of showers and thunderstorms in the afternoon and evening will put a damper on the day. Cooler weather returns for Tuesday and Wednesday as Canadian high pressure moves in. More showers and thunderstorms are possible Thursday as another storm system approaches from the plains. The expected precipitation will be beneficial with the growing season moving into high gear, as Chicago area rainfall has been spotty this spring coming off a very snowy winter.
By Meteorologist Steve Kahn
High temperatures are forecast to climb into the 70s Sunday as south winds and ample sunshine deliver holiday warmth. Winds cutting in off chilly Lake Michigan, however, will keep areas along the north lakeshore a bit cooler. It should be the city’s warmest Easter in four years since a 76-degree high on April 4, 2010.
A cool-down will follow the passage of a cold front Monday, which will be accompanied by showers and thunderstorms. Despite the Chicago area’s very snowy winter, precipitation since March 1 is running about 1.5 inches below normal. A return to cooler weather is expected Tuesday and Wednesday before another round of showers and thunderstorms arrives Thursday setting the stage for a chilly weekend with temperatures forecast to only reach the lower 50s Saturday.
Afternoon temperatures across the Chicago area spanned about 25 degrees Friday afternoon ranging from the mild lower and middle 60s well inland to the chilly middle and upper 30s near the lake chilled by brisk onshore winds. A similar, but less dramatic scenario is on tap for Saturday with lakeside areas warming to near 50 as winds become southeasterly. Spring warmth will flourish across much of the area Easter Sunday as gusty south winds boost afternoon temperatures into the middle and upper 70s bring the city it warmest Easter since 2010 when the mercury peaked at 76 degrees. Dry weather is expected to prevail through the weekend with the first chance of precipitation coming in the form of showers and thunderstorms on Monday afternoon and evening ahead of an approaching cold front.
Thanks to Valerie Baxter of Elmhurst for sending along this shot of Elmhurst newly-emerged daffodils covered with Monday late-season snowfall.
Snowfall in Chicago in mid-April is not that uncommon. Dsating back to 1885 at least a trace of snow has been reported in about two-thirds of the years from April 14th on and measurabgle snow (0.1″ or more) has occurred in a little less than a quarter of the years.
In 1961 the Chicago area was about to be hit with its largest late season snowfall when 6.8 inches of snow fell on April 15-17, the bulk of it 5.4 inches coming on April 16th. The city was hit by a 3.1 inch snowfall on April 23, 1967, just two days after the deadly Oak Lawn tornado. In 1982 the city received 1.2 inches of snow on April 16th.
Chicago has even received measurable snow in May in eight years, the biggest an official 2.2 inch snowfall on May 1-2, 1940, but many areas north and wet of the city received up to 5 inches of snow. The city’s all-time latest-in-the season measurable snowfall was 0.2 inches on May 11, 1966.
The city’s latest trace of snow occurred in June 2, 1910.
Saturday’s 80-degree warmth is but a distant memory this Monday afternoon as this spring’s persistent chill has returned. Early afternoon temperatures are holding in the upper 30s and lower 40s and brisk north wind are adding to the chill. Light sprinkles are falling across portions of the area and as colder air continues to seep into the region the precipitation is expected to gradually mix with then change to snow and increase in intensity later this afternoon and early tonight. Light snow is currently falling in north central and northwest Illinois including Rockford, Moline, Freeport, Rochelle and De Kalb, but with temperatures in the middle 30s, the snow is melting as it hits the ground.
With pavement temperatures well above freezing most of the snow should melt, but as the snow continues through the evening, some small accumulations are possible especially on grassy areas. As temperatures drop into the lower and middle 30s later this evening, some sidewalks, driveways and lesser traveled roads surfaces could gradually whiten with a covering of snow. Snowfall amounts should be minor, less than an inch, and in most cases just a few tenths of an inch.
Saturday’s 80-degree high, occurring about two weeks ahead of schedule, was an aberration in Chicago slow-starting spring. The unusual warmth lingered into Sunday morning with highs peaking around 70 before the return of a chilly northeast flow dropped the mercury into the familiar 40s that have dominated much of this spring. What may be winter’s last hurrah is expected Monday afternoon and evening when an influx of cold air will change the lingering rain to snow before ending. Most of the snow is expected to melt on contact with the warm pavements, the some snow could whiten grassy areas especially north and west of the city.
Eclipse viewing iffy
Chicagoans ability to view Tuesday’s predawn total lunar eclipse will hinge on the rate of clearing as Monday’s rain and snow pull out of the area. Latest forecasts time the clearing to coincide with the start of the eclipse, but a lingering overcast would ruin the sky show.
The Storm Prediction Center in Norman, Oklahoma has just issued Severe Thunderstorm Watch #72 for much of Iowa, southern Wisconsin and portions of extreme north and northwest Illinois valid until 5am Sunday morning.
Severe thunderstorms currently affecting portions of south central and southwest Wisconsin extending back into Iowa is expected to move to the east and south overnight and could reach northwest portions of the Chicago Metro area before daybreak Sunday morning. Large hail, gusty winds and torrential downpours and the primary severe threats from these storms.
Counties in north central Illinois included in the severe thunderstorm watch include..
Boone, McHenry, Ogle and Winnebago