Now that the three-month meteorological spring season is underway, history tells us the area’s “normal” daytime highs are likely to surge an average of 35 degrees over the coming three months and that sunshine here is to expand by well over three hours. But, it’s quite likely the area—despite a lackluster 20.3” season snow tally to date—hasn’t seen the last snow. Weather records indicate snow has fallen measurably beyond March 1 an average of six times totaling 8.1”. The numbers in a particular year can vary widely. A March 25-26 snowstorm in 1930 generated 22.3” of snow—one of the city’s biggest single snows ever. Another March snowstorm a year later between the 7th and 9th buried the area beneath 19.5”.
A few flurries are possible Thursday, but a disturbance Sunday night and Monday is the first with even the potential to produce more. That’s far enough into the future to suggest that system isn’t yet carved in stone.
--Tom Skilling, WGN-TV Meteorologist
February 2006 Archives
Another mild meteorological winter, the warmest here in four years and 7th of the past ten years to finish with an above average temperature, closes as February concludes Tuesday night. The December through February period’s 29.1° temperature ranks 38th mildest of the 135 winters on file since 1871 and 2.4° above the long term average for that period.
Chicagoans get reaquainted with an all too familiar feature of spring weather here for a second day Tuesday—northeast winds. It’s the wind direction of choice here through March, April, May and June, detested by many because of its tendency to short-circuit warming.
Chilly NE winds limited Chicago’s temperatures to the 30s Monday—20°+ colder than downstate readings, including 59° highs at Springfield, Bloomington and Lincoln. Warmth farther west established new records at Denver (73°) and at Grand Island, (77°) and North Platte (75°)—both in Nebraska.
-Tom Skilling.
The static electricity had to be near a maximum in Chicago yesterday afternoon as the relative humidity officially dropped to 17 percent at O’Hare Airport. This was the second driest February day in Chicago since 1900 (humidity records are unreliable before that time) and tied for the ninth driest all-time. Continental-source high pressure centered over southern Illinois was responsible for this rare occurrence.
Meanwhile, Californians were bracing for just the opposite—a strong low pressure system slamming into the West Coast. High wind warnings (50-70 m.p.h.) were posted for the west slopes of the Sierra Nevada Mountains along with winter storm warnings projecting as much as 6 feet of new snow above 8,000 feet and a foot or more at lower elevations. Downpours of an inch per hour were forecast for some areas with flash flood warnings up for most of the state, and mudslides were expected in recent burn areas in southwest California.
--Paul Dailey, WGN Weather Center Meteorologist
While March will probably not “roar in like a lion” this year, the first few days of the month will give Chicagoans a “feel” that spring 2006 is on it’s way. Climatology records tell us that Feb. 28 is the average date of the first occurring 60° or higher temperature in Chicago, and it might not be far off the mark this time around as the highs on Wednesday (March 1) may possibly reach the 60s at least in southern sections of the metro area. Showers and possibly even thunderstorms will probably accompany the warmer air Friday and Saturday. The passage of a strong cold front should mark a sudden change to colder next Sunday. Below normal readings will then hold over the Great Lakes well into the following week before the next storm system brings another spring-like surge of warm air and thunderstorms.
California is bracing for a tough week ahead with winter storm warnings issued for heavy snow in higher elevations while flood-producing rains are anticipated.
Friday’s weather was a study in contrasts, with springlike 60s less than 250 miles west of Chicago at the same time snow accumulated at a rate of 2” an hour to the north on the shores of Lake Superior. Duluth, Minn., was hit by 9” in just five hours while nearby Adolph, Minn., was home to the Midwest’s heaviest daytime snow tally of 14”.
Snow stands more than two feet deep across much of Michigan’s Upper Peninsula.
Though February’s 1.80” monthly precipitation in Chicago is headed for the books as the second consecutive month to produce a surplus, it hasn’t rained or snowed here at O’Hare, the city’s official observation site, in 9 days—the longest dry spell since a 14-day stretch four months ago from Oct. 3 through the 16th.
This final weekend of meteorological winter 2005-06 is to feel the part with daytime 30s. But, six years ago, Chicago’s temperature soared to 72°—a record for this date.
—Tom Skilling, WGN-TV meteorologist
Chicago’s temperatures are in for quite a ride Friday courtesy of the strongest in a recent series of Alberta Clippers to sweep into the area.
While residents of the Upper Midwest prepare for wind-driven snows Friday afternoon into Saturday, February’s second 50°+ high temperature seems likely to accompany roaring SW winds expected to rake the region this afternoon into Friday night. In combination with late winter sunlight which is more than two and a quarter times stronger than just two months ago, Friday afternoon is likely to hint at spring’s approach, though howling winds may act to temper the “warmth” a bit. Such a reading would become the 60th above normal temperature since the meteorological winter season began on Dec. 1.
One thing Friday’s clipper won’t do here is produce widespread precipitation. It’s been seven days since measurable rain or snow has fallen.
-Tom Skilling
The harsh but thankfully brief five days of sub-normal temperatures ended Wednesday as readings surged back into surplus territory, topping out at 46°. It marked the 6th time this month Chicago has reached or exceeded 40°. Nine such days are typical in February, though 11 had occurred by this date a year ago. Even so, this month’s modestly above normal temperature (+1.5°) is 5.3° behind February’s opening three weeks last year.
The frigid arctic air mass, responsible for the bitterly cold readings last weekend and a more seasonable brand of cold air (33° here Monday and 37° Tuesday) in this week’s opening days, has pulled back into Canada. The air mass was responsible for a heartstopping -48° low early Wednesday at Eureka, 700 miles north of the Arctic Circle in Canada’s vast Nunavut Territory. This in stark contrast to the 88° high in McAllen, Texas during the afternoon.
-Tom Skilling
It’s not been a great season for snow in Chicago. The city’s 20.3” seasonal tally is just 70% normal and a whopping 14.7”—just over half—the 35.0” which had accumulated by this time a year ago.
December’s 10.4” tops the area’s monthly snowfall tallies and dwarfs the 2.5” which has been measured so far this month at O’Hare. Totals through Feb. 22 have been lower in only 5 of the 26 snow seasons since 1980.
Playing a huge role in depressing these numbers has been this winter’s milder than normal temperatures. Average daily readings have been above normal on 69% of meteorological winter days.
While Chicago temperatures continue their rebound Wednesday and Thursday by pushing above 40°, an unusual chill gripped northern California Tuesday morning breaking records. Among the new cold temperature benchmarks there were 27° at Red Bluff and 29° at both Sacramento and Redding.
-Tom Skilling
Monday’s 33° high was 40 degrees warmer than the bone-chilling -7° low on Saturday—the coldest single February temperature here in a decade. While an impressive turnaround, temperature surges of that magnitude in the space of three February days are not unusual. The month has hosted 195 such thermal rebounds since records began here in 1871.
The chill of the most recent four days, while hardly a record, was formidable. The downturn ended up producing the coldest Feb. 17-20 period on the books since 1979. It was especially jarring because it came in the midst of an unseasonably mild winter. Up to the time of its arrival late this past Thursday night, Chicagoans had basked in nearly seven weeks of substantially milder than normal temperatures before the late-season arctic air crashed into the area on powerful winds. But, even with the recent chill factored in, this winter’s 28.8° average still ranks among the mildest 27 percent in Chicago.
—Tom Skilling, WGN-TV meteorologist
Chicago’s weekend subzero blast is now history as temperatures have started a rebound that will take them into the 40s later in the week. However, the moderating trend will not last, and a repeat blast of arctic air is poised to descend into the Midwest next weekend, once again sending the mercury tumbling toward single digits or lower.
Memories of a mild January and early February are fading rapidly as the final weeks of meteorological winter deal much of the nation some harsh wintry blows. Just a week ago, the East was pounded by record snowfall, while this weekend dangerous cold grips the much of the north half of the nation from the Pacific Northwest to New England. The South is also cold as an icy mix of snow, sleet and freezing rain is glazing highways from Texas to the southern Appalachians. Record lows were set Sunday at Portland Ore. (23º) and Casper, Wyo. (-17º), while Houston set a new record minimum high of 38º.
Chicago’s official low temperature dropped to -7º Saturday morning at O’Hare, cold to be sure, but not an atypical reading for a Chicago winter. What was unusual was the fact that the mercury fell below zero with no snow on the ground for only the 22nd time in Chicago out of 865 sub-0° occurrences since late 1884. It was the first time this has happened here since a bare-ground low of -8º on Dec. 14, 1985. Saturday morning lows plunged to the -15º to -20º range over deeply snow-covered southern Wisconsin, values that would have been common here had the city not been spared last week’s snowfall.
Saturday’s cold was accompanied by a sky-high 30.76” barometer, the highest value here since a 30.86” reading on Jan. 17, 2005.
After today’s subzero start, a warm-up will commence that will see temperatures rebound into the lower 40s later this week, before another cold blast descends upon the city by next weekend.
This 12th weekend of meteorological winter is to deliver the coldest February temperatures here in three years—a noteworthy achievement given the lack of snow cover. Not since 1963 has a five-day period in February hosted a more dramatic temperature pullback in the Chicago area. Daybreak wind chills open near -20° and aren’t to break above -5° today. But, the chill is even more intense to Chicago’s north. Thermometer readings under -30° combined with gusty WNW winds are producing life-threatening wind chills to -50° across a wide swath of Minnesota and Wisconsin this morning.
Chicago’s high of 24° on Friday was the city’s coldest in 59 days—since a 20° maximum on Dec. 21.
Arctic air is notoriously dry, having originated in a region that lacks access to moisture. That’s why dew points are so incredibly low today and why in the absence of additional moisture, indoor humidities will hold between 2 and 4 percent.
One of this winter’s coldest blasts to date—easily the coldest of 2006—threatens to produce sub-zero lows over much of the metro area Friday night after a day of blustery winds and single digit wind chills.
Thursday’s Wisconsin blizzard, which buried the area from Madison (9.6”) to Green Bay (13.4”), has opened the cold air spigot by covering the ground with snow, which reflects 90% of sunlight back to space before it can produce warming. No snowstorm since 1997 near Green Bay has been heavier. And 40 m.p.h. gusts produced near blizzard conditions.
Thursday’s overcast here was so dense, the day took on a dark, almost dusk-like appearance. Thunderstorms brought the heaviest rains in 6 months including 1.19” at O’Hare, 1.18” at Arlington Heights, and 0.87” at Midway. Funnels prompted tornado warnings in some southern suburbs.
-Tom Skilling
A dizzying set of temperature swings, the by-product of a mammoth winter storm draped across 14 states, is targeting Chicago. As winter’s biggest snowstorm hammers a wide swath of Wisconsin with a blizzard north of Milwaukee, downpour-generating thunderstorms threaten to sweep the Chicago area Thursday afternoon. In the wake of north suburban sleet and snow overnight, unseasonable warmth is to reach south suburban areas beyond midday Thursday. Powerful south winds are responsible and have transported unseasonably mild air more than 800 miles from the Gulf Coast. The set-up sends 60s into Kankakee and Valparaiso—and 50s reach parts of the city briefly before the bottom drops out Thursday night. The equivalent of Chicago’s October to January seasonal temperature decline is to take place in just 12 hours Thursday night.
--Tom Skilling
It felt almost springlike across the Chicago area Tuesday. The afternoon high surged to 56°—just 6° off the mildest Valentine’s Day temperature on the books here: 62° in 1954. It was 2006’s second warmest day. Only January 12 produced a higher temperature (57°). The unseasonable warmth established new high temperature records for the date in Cedar Rapids (63°) and Dubuque (59°)—both in Iowa. The 59° in nearby Rockford tied the record.
But, near 0° temperatures from North Dakota through northern Minnesota late Tuesday signaled the big weather changes are on the way.
The coming weekend threatens to be one of the coldest of the winter. Only the stronger sunlight of February has a chance of tempering the full impact of the incoming cold air, which may arrive over a fresh cover of snow most favored over northern counties north into Wisconsin.
-Tom Skilling
For only the fifth time this year, Chicago’s temperature appears headed to 50° or higher Tuesday. Nearly eight out of 10 Februarys have included at least one 50° day, so there’s nothing especially surprising about a reading at that level this time of year. But, such temperatures aren’t everyday occurrences in February. The predicted high of 52° Tuesday is 18° above normal and easily qualifies as our mildest temperature here since 55° on Jan. 19—more than three weeks ago! Chicago’s last 40°+ high (44°) occurred on Feb. 3
The mild air mass sent readings in the Plains soaring to the 50s and 60s Monday. While Miami, Florida only made it to 58°, Rapid City, S.D. surged to 59° while a series of Nebraska communities made it into the 60s, including Hastings with 64°, Hebron at 65° and McCook topped out at 63°.
The entire Florida peninsula was placed under a freeze warning Monday night.
-Tom Skilling
As the East Coast digs out of a record-breaking snow storm, Chicagoans look at a disappearing thin cover of white left behind by lake-effect snow showers the past couple days. Moderately strong southwest winds will bring a gradual warming to northern Illinois, pushing Chicago’s high temperatures into the 40s starting Tuesday and continuing into Thursday. However, low pressure will develop in the central Plains and move northeast, spreading rain over the area Thursday. A huge cold high pressure air mass in south-central Canada is poised to drop into the Midwest behind the low, bringing a potential 40-degree change for Chicago from Thursday’s highs in the 40s to single-digit lows Friday night.
Back in the East Coast, snow was still falling in some areas Sunday night, but storm totals were well over 10 inches over a wide expanse from North Carolina to Maine. As the blizzard subsided, New York City, hit by the epicenter of the storm, was at a standstill.
Blizzard warnings were posted for the northeast and heavy snows were expected along the East Coast from the mid-Atlantic to New England including the Appalachians overnight and this morning. New York City and Boston braced for blizzard conditions with forecasts of 50 m.p.h. winds, over 15" of snow and extensive drifting. Some areas of New England were anticipating up to two feet of new snow. Travel was expected to be at a standstill this morning all along the east coast from Virginia to Maine. Yesterday the strong upper air low responsible for the east coast system was centered over the lower Ohio Valley and convective clouds that developed under the cold core air aloft dumped 5 to 7" of new snow over southern and central Illinois. Heavy snow showers also occurred in southern Indiana and Kentucky. Cold air spread deep into the Gulf of Mexico with Florida bracing for freezing temperatures Monday and Tuesday mornings.
As much snow fell Friday in Memphis, Tenn., as typically falls over an entire season. That city’s 3-5” accumulations are but the opening salvo of a winter storm expected to race into the Boston-New York-Washington, D.C. corridor with 6-10” of snow amid increasing winds. Rapid intensification once the system has access to moisture and heat energy over the Atlantic Saturday threatens to turn the snowstorm into a blizzard over New York City and coastal southern New England including Boston. Winds there could gust to 50 m.p.h. as hourly snow rates increase to 2-3” per hour Saturday night.
Though well to its west, Chicago isn’t completely escaping the storm’s impact. North winds between the East Coast low and a sprawling Canadian high in the Rockies set the stage for the city’s second lake-snow event in four days. Wind trajectories off the “warm” lake waters favor waves of lake-enhanced snowfall of varying intensities Saturday.
There have been few streaks of above normal temperatures quite like it in 136 years of weather records. Until Thursday, 48 consecutive days spanning what is typically the year’s coldest period here, posted temperature surpluses. The warmth was so dramatic, the city’s temperature ranking slipped an unprecedented 107 slots, moving in just under 7 weeks from 4th coldest to 111th coldest of all Dec. 1 through Feb. 8 periods on the books since 1871. The chill responsible for bringing the mild spell to its unceremonious end Thursday produced 2006’s lowest temperatures, including a 16° morning low at O’Hare and lows of 6° at west suburban Aurora and 9° at Rockford. Even colder readings gripped areas to the north. Perennially cold Embarrass, Minn. took honors for coldest Midwest location with its -20° morning low while Hayward, Wisc. bottomed out at -10° and nearby Rhinelander posted -7°.
-Tom Skilling
Bursts of visibility-slashing lake-effect snow descended on Chicago and parts of Illinois, Wisconsin and Indiana counties bordering Lake Michigan, generating stunning weather variations across the area Wednesday. While cold, snow-free weather was front and center over a majority of the metro area, the weather seesawed dramatically between near whiteout conditions one moment and bright sun the next over a narrow corridor 220 miles long and less than 20 miles wide, originating to Chicago’s north over central Lake Michigan, then extending south/southwest into Lake, Cook and Will counties in Illinois and east to Lake County, Indiana. Radar scanned cloud tops as high as 9,000 feet—twice the height of flurry-generating lake-effect clouds. Several inches accumulated at hardest-hit locations.
Residents shivered with a 30° high here for only the second time in 2006 (the other occurred Jan. 23). By this time a year ago, there had been 14 highs below 30°.
The remarkable 47-consecutive day run of mild weather, which started in the final days of December, ends Wednesday with the arrival of the city’s first below-normal temperatures since Dec. 22. The unprecedented string of above normal readings has radically altered Winter 2005-06’s temperature ranking. What was once the 4th coldest winter on record back in December has surged to the 26th warmest spot here since 1871, good enough to rank among the mildest 19% of cold seasons on the books here. That news follows the official word late Tuesday from NOAA’s National Climatic Data Center, that Lower 48 residents experienced the mildest January on record (since 1895) last month.
Cold weather tightens its grip on the area this weekend. Wednesday’s lake snows may not be the last. Another disturbance brings snow back to the area Thursday night—and spells of flurries will come and go in the coming 7 days.
-Tom Skilling
There’s nothing like a trek across bare ground to ease the impact of an arctic air mass. That’s what’s happened in recent days. Snow cover reflects incoming sunlight away, reducing warming. But, bare ground has the opposite effect. Its dark color absorbs sunlight, a process which produces warming The difference between bare and snow covered ground can be dramatic. A combination of snow cover, clear skies and little or no wind at night has been known to reduce temperatures 12 or more degrees. By the same token, daytime readings surge 6-12° when the ground is bare. Despite the bare ground, readings are running 15-20° below the highest levels of the past six unseasonably mild weeks. But, while eastern North American temperatures have cooled, the same pattern change has boosted readings dramatically to the west. In just the past three days, Fairbanks, Alaska has warmed from -40° to Monday’s 34°—a 74° increase!
-Tom Skilling
Even though it’s gotten colder, daytime readings are still registering at seasonable levels in the lower 30s. That should change by next weekend, however, as two reinforcing surges of arctic air finally send the mercury plunging to levels not seen here since Dec. 21. Several periods of snow showers will occur through the week, but significant snowfall is not expected with the exception of the favored lake-effect snow belts of northern Indiana.
In contrast to the mild weather that has been so prevalent across Chicago and the Midwest for the last six weeks, cold weather—even by Alaska standards—has been gripping our northernmost state. An all-time record low of -56º was set on Feb. 3 at Point Lay on the western Arctic coast, while nearby Barrow’s low of -55º (also on Friday), came within one degree of that location’s lowest reading ever set back in 1924.
Chicago’s spectacular run of mild weather is over. After six weeks of above normal temperatures, the city is bracing for a dose of mid-winter reality. Arctic air is flooding into the Midwest on the back side of a major winter storm that is bringing a “super” snow to the Super Bowl in Detroit.
While portions of the eastern Midwest and lower Great Lakes may see a foot or more of snow from this storm, Chicago will escape with just enough to whiten the ground. However, snow could accumulate several inches just to our east in the lake-effect snow belts of northern Indiana.
On a sad note, the Chicago meteorological community is mourning the sudden and unexpected passing of Joe Bicek. Joe, a cooperative weather observer in Lake Villa for more than 30 years was well known and respected for his timely and accurate weather observations. He was a constant contributor to our WGN and Tribune weather efforts. Our condolences and prayers go out to his family.
The similarity between the track of a blizzard-generating system which crippled much of the Midwest in January 1978 and Saturday’s developing storm to Chicago’s east is striking.
It’s among the reasons forecasters are monitoring Saturday’s storm very closely, though today’s storm is to attain a 982 mb (28.99”) central pressure—a fraction of the astounding 959 mb (28.31”) pressure in the ’78 storm. What really set the ’78 system apart from most winter storms was the remarkably large area from Pennsylvania west to Illinois buried beneath 1-3 foot snows whipped in places into 10-15 foot drifts. Chicago’s 12.4” closed O’Hare Airport for only the third time up to that point.
Any westward jog in the path of Saturday’s storm could have major implications for Chicago. At present, flurries Saturday morning are expected to build to snow or snow showers Saturday afternoon and/or night on the storm’s far west side.
The last time mid-winter temperatures were any higher than those we’ve experienced over the past 43 days was the Winter of 1932-1933. This year’s 36.0° average temperature since Dec. 23—a reading 11.4° above the 24.6° long term average—was exceeded that winter by just 0.6°. The February which followed underwent stunning changes. Weather balloons weren’t launched in that era, so it’s impossible to know precisely what role any shift in high altitude steering winds played in the arctic outbreak which followed.
The temperature plunge here was breathtaking and hit within 8 days of February’s open. From 48° on the 1st, Chicago’s temperatures plunged 67° to -19° the morning of Feb. 9. Surface weather maps indicated a massive arctic high, boasting a barometric pressure exceeding 30.65” crashed southward into the country from Canada to produce to temperature dive. The chill didn’t last. Highs in the 50s returned in the month’s final week.
Chicago’s remarkable 42-day run of above normal temperatures, one of the city’s five longest in 136 years, is running out of steam. Only five strings of daily temperature surpluses have lasted longer in Chicago —the longest among them, one spanning 54-days in 1921, 52-days in 1931, 50 days in 1989, 49-days in 1998 and 44-days in 1947.
Not a single day in the Chicago area since Dec. 22 has fallen below normal. Thursday’s predicted 40s—and even Friday’s marginally reduced readings in the upper 30s--promise to keep the string of above normal daily temperature averages going two more days. But cooling this weekend promises the first temperature deficits in over 6 weeks, albeit modest ones in the early stages of the pattern change.
As any Chicagoan knows, February is perfectly capable of producing frigid weather. A quarter of the single digit or sub-zero temperatures have occurred historically beyond Feb. 2.
