EXPLAINER: January 2008 Archives

--By Tom Skilling, WGN-TV Chief Meteorologist

--By Paul Dailey, WGN Weather Center Meteorologist

--By Tom Skilling, WGN-TV Chief Meteorologist

--By Tom Skilling, WGN-TV Chief Meteorologist

--By Tom Skilling, WGN-TV Chief Meteorologist

--By Paul Dailey, WGN Weather Center Meteorologist

--By Tom Skilling, WGN-TV Chief Meteorologist

With arctic air returning to the Chicago area and the Midwest this week, snow and colder weather are on tap instead of the recent siege of unseasonable warmth, rain and storminess.
A series of cold fronts are expected to pass through the area, each accompanied by a period of snow or snow showers and followed by a shot of arctic air. The coldest air will hold off until the end of next week, when strong northerly flow is expected to keep highs in the teens and send overnight lows below zero for the first time this winter. However, a build-up of at least an inch or two of snow cover here will be necessary to help maintain the strength of the incoming cold air.
Levels are falling, but many areas on the Illinois, Kankakee and Iroquois rivers (along with many streams and creeks south of Chicago) remain above flood stage. With colder weather ending the threat of additional rain, river levels should continue to fall over the next few days.
--By Steve Kahn, WGN Weather Center Meteorologist

Saturday's expected 40-degree high may be the city's last maximum temperature to reach that level for quite a while.
Frigid air which has been confined to areas far to the north across northern Canada in recent days is ready to begin a plunge south into the United States again, propelled by a buckling of the jet stream that will open the arctic floodgates.
The cold air will arrive here in progressively colder stages, each proceeded by a period of snow that should re-establish some snow cover in the region.
Though a large snowfall does not appear to be in the cards, even a few inches of snow would go a long way in sustaining the newly arriving deep freeze.
Cold air swept into Iraq Friday, where Baghdad experienced its first snowfall in memory. The snow, mixed with rain at times, melted quickly. High temperatures there in the middle 30s were more than 20 degrees below normal.
--By Steve Kahn, WGN Weather Center Meteorologist

As snow flurries end this morning in the wake of low pressure departing to the east, another strengthening low pressure system in the northern Plains is headed this way and forecast to give northern Illinois more snow later Saturday night and Sunday.
Temperatures will be slowly trending lower with succeeding fast-moving low pressure systems next Monday and Wednesday. Frigid arctic air will follow a strong cold front next Wednesday and dominate the remainder of the week.
Unusual January severe weather broke out along the mid-Gulf Coast Thursday. By Thursday evening, five people were injured and extensive property damage was reported after 17 tornadoes hit Mississippi, Alabama and Louisiana). To top it off, three tornado touchdowns occurred in the southwest corner of Washington in Clark County. The nation's tornado total thus far this January is more than triple that recorded as of this date last year (87 vs. 27).
--By Paul Dailey, WGN Weather Center Meteorologist

This week's unseasonable warmth is now history, and is soon to be replaced by colder weather and snow. Temperatures during the three-day Sunday-Tuesday warm spell averaged 30 degrees above normal, placing it fourth among similar January warm spells since 1871.
The next storm system which will arrive Thursday will begin as rain here, but a change over to snow can be expected Thursday night into Friday as colder air sweeps into the area on the storm’s backside. Heaviest accumulations appear headed for Wisconsin and Michigan where up to 6 inches of snow could fall.
The mercury will continue its downslide through the weekend, and the latest ensemble of long-range computer forecasts predict even colder air is to reach the Midwest and Northeast in the period beyond Jan. 20.

--By Steve Kahn, WGN Weather Center Meteorologist

The warm spell made this just the 4th January since 1928 to produce 3 consecutive high temps of 55°+. Thunderstorm-driven severe weather and heavy rains have moved east, leaving behind tornado damage and rain-swollen rivers. Only the second January tornado in this area since at least 1950 cut a 15-mile swath from Popular Grove to Harvard in McHenry County Monday afternoon. Later Monday into Tuesday, “training” storms, repeatedly developing and moving over the same area ahead of a slow-moving weather system gave widespread rain totals from 1 to 5”. A band of 4”+ rainfall extended from Pontiac in Livingston County east into southern Newton and Jasper Counties in Indiana. Due to saturated soils, most of the rain was runoff into area creeks and streams, resulting in major rivers south of I-80 being near or in flood. Temps will fall the remainder of the week with highs next week in the low to mid 20s.

--By Paul Dailey, WGN Weather Center Meteorologist

Swarms of at least 30 tornadoes blasted portions of the Midwest from southwest Missouri to southeast Wisconsin Monday afternoon and evening, producing at least one fatality, numerous injuries and swaths of devastation. Prior to Monday, the state of Wisconsin had only one January twister on record, occurring near Janesville back in 1967, while the closest twister to northeast Illinois struck near Kankakee on January 24, 1950.
All that changed in less than an hour on an unseasonably warm mid 60º January afternoon as a series of twisters inflicted major damage along a line from just north of Rockford to just west of Racine in southeast Wisconsin. At least three people were injured in Boone county where storm debris made roads impassible near Poplar Grove. Some of the worst damage was inflicted near New Munster, Wisconsin west of Kenosha where 12 homes were destroyed.

--By Steve Kahn, WGN Weather Center Meteorologist

Not only did Chicago eclipse the 54 degree record high originally set in 1907 when the mercury reached 60 degrees Sunday afternoon, but the day's 41 degree low also established a new record high minimum, wiping the previous record of 40 degrees (also set in 1907) from the books.
With a strong southerly flow of air expected to blast the city again on Monday, it's a good bet that more records will tumble. With high temperatures forecast to reach the lower 60s, the Jan. 7 record high of 59 degrees (set in 1907) appears to be in jeopardy, and with downstate readings on Sunday climbing well into the 60s, it is not out of the question that the city's all-time January high temperature of 67 degrees, established on Jan. 25, 1950, could be equaled or surpassed.
However, the unseasonable warmth will be fleeting. Colder air poised to sweep into the area beginning late Tuesday sets up a gradual temperature decline expected to last for the rest of the week.
--By Steve Kahn, WGN Weather Center Meteorologist

Just three days after Thursday morning’s 0º low, Chicago area temperatures are threatening to break Sunday’s century-old 54º record high established in 1907. The stunning 50º+ temperature rise is rapidly devouring the area’s snow pack, releasing more than half an inch of meltwater into area soils. Coupled with the potential for copious rainfall from an approaching storm, area rivers, streams and creeks may experience rapid rises.
The storm promises to be a potent offshoot of the major system that crippled portions of the West with 100 m.p.h + winds, up to 6 feet of mountain snow and mudslide triggering deluges.
Being January, the abnormal warmth will, of course, be fleeting, with colder weather and some snow showers set to return to the Chicago area and the Midwest later in the week.
--By Steve Kahn, WGN Weather Center Meteorologist

Southerly winds generating low-level cloudiness, fog and a drizzle/light shower mix are the driving forces behind an expected rapid snowmelt over northeast Illinois this weekend. Temperatures rise steadily into the lower 40s today, hover at that level overnight, and then climb into the lower 50s Sunday -- possibly approaching the record high of 54 degrees set 101 years ago. This strong southerly flow over the central Plains and Midwest has been set up by a monster low pressure system off the northwest U.S. coast. Winds gusting over 100 m.p.h. have pounded northern California. Santa Clara, Ben Lomond and Big Sur, all south of San Francisco, respectively received 10, 8 and over 6 inches of rain. Meanwhile, just to the east in the higher Sierras, Aspendell had 16 inches of snow in 4 hours and Placer had 163 m.p.h. winds.
The storm will move across the Rockies, developing a low in the central Plains that will bring heavy rains and potential flooding here early next week.
--By Paul Dailey, WGN Weather Center Meteorologist

As frigid high pressure moved east, southerly flow returned to Illinois Thursday. The opening three days of January 2008 averaged some 10° below normal, 25° colder than a year ago. Arctic air penetrated deep into Florida with snow flurries observed at Daytona Beach. Citrus growers were pressed into protective actions with 29° at Tampa, and 31° at Orlando. Miami hit a low of 39°. Noticeable warming begins today, then picks up momentum this weekend. The strong weather system presently lashing the west coast with damaging winds and heavy rains (snow at higher elevations) will cross the Rockies and force the development of a low pressure system that will move through the Midwest early next week. This will mean an extended period (into next Tuesday) of southerly flow that will feed mild moist air over Northeast Illinois’ shrinking snow layer resulting in drizzle, fog and showers.
--By Paul Dailey, WGN Weather Center Meteorologist

Early-bird risers who step into sub-zero temperatures this morning might find it hard to believe, but it’s true: The city will be basking in 50° readings (or higher) in another three days.
A major weather pattern shift begins haltingly on Friday as upper winds that have been blowing with considerable strength from the northwest gradually diminish and are replaced by southwesterlies. Southwest winds, surface and aloft, strengthen on Saturday, then persist through Monday.
Mild, moist air from the Gulf of Mexico arrives here on Saturday and, as that air spreads across our snow-covered landscape, it becomes a recipe for a heavy gray overcast, widespread fog and plenty of light rain and drizzle through the weekend. The multi-inch layer of ice and crusty snow that blankets the area today will be history by Monday.
-By Richard Koeneman, WGN Weather Center Meteorologist

Chicagoans shivering in today's arctic cold can take consolation in the understanding that they are not alone.
Very cold air -- bitterly cold in some regions -- holds all of the nation east of the Rocky Mountains in its frigid grip. That constitutes literally two-thirds of the Lower 48.
Lake-effect snow swirling off Lake Michigan continues to cause problems today for residents of the snow-belt areas of northern Indiana and southwest Lower Michigan (and downwind of the other Great Lakes, as well) -- but they take that in stride.
Residents of the Deep South, however, are far less accustomed to the presence of harshly cold winter temperatures. Freezing conditions are pushing literally into south Florida -- and that's not the end of it. "Northern air," greatly modified but still chilly, is forecast to push across the north half of the Caribbean Sea by Friday.
--By Richard Koeneman, WGN Weather Center Meteorologist