EXPLAINER: October 2008 Archives

Readings soared into the 70s across the Chicago area Friday -- the region's warmest in
18 days and only the fifth 70-degree or higher temperature in October. A typical
October produces nearly twice as many.
O'Hare Airport's 70-degree high was the mildest Halloween reading here in eight years.
Even warmer readings were observed in other parts of the area. Northerly Island
reached 73 degrees while the WeatherBug sensor in Libertyville and New Lenox recorded
75 degrees. Highs of 73 degrees were reported at DeKalb and Plainfield. Warmest of all
was Burlington, Wis., where the mercury hit 79 degrees.
October 2008 closed 6.3 degrees cooler than its 2007 counterpart, but still managed to
be 0.6 of a degree warmer than normal.

RESURGING WARMTH PROMISES
NEAR-RECORD ELECTION DAY HIGHS
The passage of a cool front overnight has introduced northeast winds which slash
temperatures here by at least 14 degrees Saturday. But the front moves north of the
area Sunday afternoon, placing Chicago back in unseasonably mild air expected to last
through midweek. South winds and abundant sunshine could push Election Day
temperatures to near-record levels here.
--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune

Chicagoans basked in the first 60-degree temperatures in 11 days Thursday. The
mercury reached 62 at O'Hare International Airport just before 4 p.m. and 63 at Midway.
Even warmer readings were reported at Rockford (65 degrees), Joliet (66), St. Charles
(66), Marseilles (67), Morris (68), and Peru (70). Converging winds ahead of a
southbound late-day cold front Friday are likely to drive readings even higher on
Halloween with 70-degree temperatures a distinct possibility.

The warm-up dominates much of the country's Heartland. In Marquette, Mich., where 2
inches of snow fell Monday, high temperatures Thursday soared to 64 degrees -- a new
record and even warmer than Chicago's high. The dome of warm air produced 80s in
sections of the Plains just east of the Rockies including 82 degrees at Boulder, Colo.,
and 82 at Kearney, Neb.

FAIRBANKS, ALASKA TO CLOSE BOOKS ON 4TH COLDEST OCTOBER EVER

Bitterly cold air has gripped our 49th state over the past week. At Chandalar Lake,
Alaska, temperatures plunged to 42 degrees below zero. In Fairbanks, the books are
poised to close on the city's 4th coldest October.

--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune

A mild late-autumn pattern is poised to take over from the chill of recent days. The
cold readings of late have slashed October's average temperature to 52.6 degreesa --
6.8 degrees cooler than the same period a year ago and 1.7 degrees below the 137-year
average. That places this month among the coolest third of Octobers on the books here
since 1871.

The U.S. was a country meteorologically divided on Wednesday between the record-
breaking morning chill that gripped Florida -- nearly all of the state's weather
observing stations recorded new lows -- and surging readings in the Plains. Down-
sloping winds compressed and warmed in the Dakotas sending afternoon highs to 78
degrees at Dickinson -- a record. The mild air is surging eastward and is behind the
warm-up predicted for Chicago. Highs in the 60s on Thursday and Friday mark the first
time in 11 days readings have broken above 60 degrees.

If Friday's high temperature matches the 69-degree prediction, it would make
Halloween 2008 the warmest since the 68 degree Halloween high in 2001.

ELECTION DAY (TUESDAY) COULD BE THE MILDEST HERE IN 44 YEARS

--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune

The powerful early season cold blast in recent days responsible for Chicago's chilliest
weather in 6 months, and freezing temperatures south to Florida, produced explosive
storm development on the Mid-Atlantic coast Tuesday. Barometric pressure readings
-- a gauge of storm intensity -- went into a 12-hour dive which revved coastal winds
to gale force (39+ m.p.h.) while burying northern New Jersey, eastern Pennsylvania and
a swath of eastern New York beneath one of the region's heaviest early season
snowfalls. National Weather Service forecasters ranked the 17 inches that fell in
northeast Pennsylvania as that area's heaviest early season accumulation in at least
three decades while the 14 inches measured at High Point State Park, N.J., was that
state's heaviest early snowfall on record. New York fared little better. New Kingston was
buried beneath 15 inches. Winds drove rain horizontally in Cape May, N.J., and roared at
velocities up to 66 m.p.h.

By contrast, temperatures in the Plains soared 25 degrees Tuesday afternoon over
readings 24 hours earlier. The eastbound mild air promised relief from the chill in the
Midwest.

--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune

The coldest temperatures in nearly seven months will have Chicagoans shivering as
Tuesday gets under way. The mercury dropped into the 20s at O'Hare and over many
areas away from Lake Michigan overnight. It's the first time since the 28-degree
minimum on April 2 that the city's official low temperature dipped below 30 degrees.
The chill, which prompted frost and freeze advisories across sections of 17 states
overnight, is part of a massive early season cold air incursion that sent temperatures
plummeting into the 30s south to north Florida and the Gulf Coast.

Lake-effect rain and snow showers have targeted northwest Indiana and lower
Michigan. Snow covered the ground in the northern Midwest, with accumulations of 3
inches at Eagle River, Wis, and 2.2 inches at Marquette, Mich.

2008 GROWING SEASON ENDS 3 DAYS SHORTER THAN NORMAL

With sub-freezing temps overnight, the 2008 growing season has come to an end. The
growing season is the period between the last frost of spring and the first frost of fall.
Normally 183 days in length, this year it was 180 days.

--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune

Chicagoans got a sneak preview of upcoming winter Sunday afternoon as strong
west-northwest winds swept remaining leaves off trees and brought a late-autumn
chill into the area. Early afternoon readings that peaked in the middle and upper 50s
had dropped into the 30s by evening after an afternoon that featured rain, snow
showers and some small hail. Highest wind gusts were clocked at 61 m.p.h. at West
Chicago, Gary and the Harrison-Dever Crib. Sunday's winds produced scattered tree
damage and power outages throughout the city and suburbs.
Several locations reported snow pellets Sunday afternoon including the official O'Hare
site, marking the start of the 2008-09 snow season five days ahead of schedule.

FREEZE TO END GROWING SEASON; SHARP WARM-UP TO FOLLOW
Frosts have occurred in scattered inland areas already this fall, but this vigorous cold
snap should bring widespread subfreezing temperatures to many inland areas this
morning and to much of the region tonight with the possible exception of the
immediate lakeshore. Southwest winds return by Wednesday, sending the mercury back
to the 60s by Thursday and Halloween.
--By Steve Kahn, WGN Weather Center Meteorologist

West winds will howl across the Chicago area Sunday, a harbinger of the season’s first
cold-air blast that will send the mercury tumbling to its lowest levels since April.
Though readings peak in the middle 50s on Sunday, west winds will gust as high as 50
m.p.h. as the colder air arrives. Skies will cloud over by evening as temperatures fall
through the 40s and into the lower 30s by Monday morning, which could bring not only
the season’s first freezing temperatures but the first snow flurries as well. The
combination of gusty northwest winds and high temperatures struggling to reach only
the lower 40s Monday will give the day an early-December feel. The chill will be
fleeting, as readings rebound to the middle and upper 50s midweek, setting the stage
for a mild Halloween with temperatures surging into the 60s.

MIDWEST’S FIRST WINTER STORM WATCHES IN WISCONSIN, MICHIGAN

The system responsible for Chicago’s chill will bring lake-effect snowfall to portions of
the upper Midwest downwind of Lake Superior. Winter storm watches have been posted
for up to 8 inches of snow from Bay- field, Wis., to just south of Upper Michigan’s
Keweenaw Peninsula by Monday.

Lightning flashed late Friday from low-topped thunderstorms across the Chicago area.
The storms bubbled into existence as a pool of unseasonably cold air at the heart of a
slow-moving storm system aloft swept directly overhead. It's a development which
encouraged 54-degree air at ground level to ascend into subfreezing air hovering less
than a mile above the surface and fostered hailstone formation. Quarter- to
half-inch-diameter hail was reported at Sugar Grove, Pecatonica, Elburn, Plano and
Flossmoor, as well as Munster and Crown Point in Indiana. The rainfall spawned by the
storm had pushed Midway Airport's two-day tally to 0.65 inches by late Friday. Heavier
rain totals occurred to the west where 1.01 inches fell at Pontiac, 0.92 inches at Morris
and 0.87 inches at Marseilles.
A classic high-wind scenario threatens to take shape Sunday as west-northwest surface
and jet stream winds align.
Subsidence as arctic air approaches could mix 40-50 m.p.h. gusts down to the surface --
inducing compressional warming which initially delays the onset of the coldest air but is
still likely to whisk the coldest air in six months into the area Sunday night and Monday.
--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune

The powerful easterly winds that tapped dry air for a time and held rain at bay much of
Thursday finally eased and yielded to rain late in the day. The winds were behind
6-foot-high waves that pounded the Illinois shoreline for a time. But as velocities fell,
the atmosphere became saturated with moisture and the heavens opened. Rains that had
drenched areas of Illinois west and south of Chicago much of the day began falling in the
western suburbs from Aurora and Joliet around 4 p.m. and began falling in the city around
6 p.m. Downstate rainfall totals included 1.10 inches at Marion, 1.09 inches at Effingham
and 1.01 inches at Decatur. Nearly 0.70 inches fell in St. Louis.
TEMPS PLUNGE LATE SUNDAY AS ARCTIC FRONT HITS WITH 30 M.P.H.-PLUS WINDS
Big changes loom early next week as a strong cold front passes through the city Sunday
afternoon, sending readings plummeting from highs near 60 degrees midday to the
lower 30s by Monday morning, bringing not only light showers or sprinkles but
possibly the season's first snow flurries. Highs on Monday will struggle to reach the
lower 40s, a level more typical of late November or early December.
--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune

Gusty east to southeast winds, which took hold Wednesday afternoon, continue
Thursday. They're part of the circulation of a powerful autumn storm that has drenched
the Plains and western Midwest in recent days. Rainfall exceeded 3 inches there
Wednesday as powerful 55+ m.p.h. gusts raked an area from South Dakota to Kansas.
The wind, in combination with a 2-inch coating of wet snow, downed trees in O'Neill,
Neb., while 4.16 inches of rain doused Beaver City in south-central Nebraska. A
blizzard warning was issued for northwest Kansas and motorists were warned that 50
m.p.h. winds and heavy snow threatened to slash visibilities to a quarter-mile or less
with local white-out conditions into Thursday.

The storm, cut off from a powerful jet stream steering winds to the north, is only
expected to crawl across the Midwest, delaying rain's arrival in Chicago until early
Friday. Once here, rainfall could reach a half inch or more.

SEASON'S COLDEST CHILL YET BOOSTS LATE WEEKEND FLURRY
POTENTIAL

Early-season arctic air brings back-to-back 40s Sunday and Monday. Sprinkles could
mix with some flurries.

--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune

Wednesday dawned with frost in a number of western suburbs for a second consecutive
morning. The overnight chill followed Tuesday's 55-degree high -- a reading in stark
contrast to the 80 degrees recorded a year earlier. Tuesday's chilly high tied for fall
2008's coolest.

To date, October is running a modest 1.3-degree surplus. But the month's average
temperature is well behind a year ago. While Chicagoans have been treated to one
80-degree day earlier this month, eight had occurred in October 2007.

A storm taking shape in the Plains is eastbound and likely to bring wetter weather
toward Friday. Eight of the 13 most recent computer models suggest rains of a half
inch or more will fall across the Chicago area with the late-week storm.

FALL HARVEST WELL UNDER WAY -- 2 WEEKS OF GOOD WEATHER NEEDED

Will County farmer John Hazzard reports that 95 percent of soybeans and 35 percent of
the corn in his area have been harvested -- ahead of the statewide average reported
earlier this week by USDA. Area farmers would like to see another two weeks of good
weather to finish their fieldwork, but may have to contend with late-week rain.

--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune

The lake-effect rain machine will be active Tuesday, particularly in the morning. Not
only have the chilly north winds that greet Chicago morning commuters traveled the
length of Lake Michigan, the atmospheric setup also features a temperature decline
between the lake surface and a mile aloft of 30-degrees. That's a much steeper drop
than normal. A decrease of just 20 degrees is enough to encourage air to rise and cool
producing lake clouds -- so Tuesday's elevated decrease goes even further in
encouraging the comparatively mild air hugging the lake surface to ascend and cool --
a prerequisite for cloud and shower formation.

The lake setup breaks down Tuesday afternoon and chilly temperatures Tuesday night
threaten frost away from the lake. Monday's 55-degree high is the chilliest of the fall
season to date. It's also the coolest since May 28.

ATMOSPHERIC STIRRINGS OVER GREENLAND AND NORTH ATLANTIC SIGNAL
NEW CHILL HERE NEXT WEEK

Buckling of jet stream is to set up northwest flow aloft over the Midwest.

--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune

Just a week ago Sunday, the city basked in bright sunshine and record-tying mid-80
degree warmth -- but after readings struggle to reach 60 degrees Monday, the mercury
will be hard-pressed to get out of the 50s the rest of the week.
Slow-moving low pressure is forecast to develop, bringing the Midwest several cloudy,
damp and rainy days. Late-October 70 degree-plus warmth is not uncommon in
Chicago, having occurred in seven of the past 10 years -- but current outlooks
preclude any such rebound through the end of the month.
In addition to the inevitable late-autumn cool-down, the city is also approaching its
cloudiest time of the year. November and December average just 40 and 39 percent of
possible sunshine respectively, a large drop from October's 58 percent. This week's
dominant cloud cover should provide a preview of the upcoming dreariness.

ATLANTIC HURRICANE ACTIVITY
QUIETING DOWN AFTER A BUSY SEASON
The Atlantic Basin is currently storm-free after Hurricane Omar's recent demise, though
about six weeks still remain in the 2008 season which ends Nov. 30.
--By Steve Kahn, WGN Weather Center Meteorologist

Strengthening southerly winds and abundant sunshine should allow temps to warm into
the mid-to-upper 60s Sunday afternoon. As a cold front approaches from the
northwest, clouds will spread across northern Illinois Sunday night acting as a blanket
to keep overnight temperatures mostly in the 50s. The cold front should move through
northeast Illinois Monday afternoon, preceded and accompanied by scattered brief
showers. Winds will shift to the north, and cooler air on the leading edge of a Canadian
high pressure air mass will feed into the metro area holding over the Midwest through
Wednesday.

LOW PRESSURE FORMS IN THE PLAINS

By midweek, a pocket of very cold air aloft is forecast to sweep out of western Canada
into the central Plains, creating a “cut-off low pressure system”. This slow-moving
system develops a broad area of cloudiness and showers. Showers may be mixed with
wet snow on the backside of this storm system. As the eastward-moving low center
approaches Kansas City, Mo. later Wednesday, the leading edge of the expansive cloud
pattern will spread over Chicago. Rain will begin here Thursday and persist into next
weekend.

A 57-degree reading recorded at 10:59 a.m. Friday proved all the atmosphere here could
muster. It was the second consecutive day readings failed to reach 60 degrees -- the first
time that's happened in nearly five months. Rain falling into a dry layer of air and
evaporating Friday afternoon -- a process meteorologists refer to as "evaporative cooling"
-- sent temperatures falling to late-November levels. By mid-afternoon, readings had
retreated to the mid-40s in Wheaton, Naperville, Darien and Frankfort -- easily the
coolest since May 27. Friday's chill followed a night of 30s in many suburban areas --
with cool air responsible for frost at some locations. Clouds eventually break Saturday --
but Sunday appears to be this weekend's real winner as gusty south winds bring a
temperature surge to Chicago. Though a far cry from last Sunday's record 84 degrees at
O'Hare Airport, Sunday's 70-degree high will be a 12-degree improvement over Saturday's
58. A system taking shape later next week threatens wetter weather. And at least four
punches of cool air are possible in October's remaining days. Despite recent chills,
October to date here is more than 2 degrees above normal -- but is running 4.8 degrees
behind a year ago.
--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune

Temperatures struggled to 59 degrees Thursday at the three major Chicago weather
reporting locations -- O'Hare and Midway Airports and Northerly Island. It marked only
the second time this autumn the mercury has failed to reach or exceed 60 degrees, the
fewest sub-60-degree highs to occur this far into the fall season since 1966 when only
one high had remained below 60 degrees. The chill continues Friday with a second day
of 50s predicted -- the first time back-to-back 50s have occurred here in nearly 5
months.

Some lake-effect clouds greet Chicago as Friday dawns. Temperatures drop 27 degrees
in the first mile of the atmosphere -- supportive of lake cloud development. The steep
vertical temperature decline encourages air to rise from the lake surface, cool and
condense producing clouds. But with an easterly flow in place, winds travel over 80
miles of the lake, allowing little time for significant moisture to evaporate and fall as
rain.

60 OF PAST 80 YEARS HAVE PRODUCED MULTIPLE 70s BEYOND OCT. 17

A 70-degree high is predicted Sunday. Weather records indicate an average of four
70-degree days occurred beyond this date.

--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune

Autumn's chill is in the air. Not since back-to-back daytime 50s occurred here nearly
five months ago on May 22 and 23 -- 59-degrees and 57-degrees respectively -- has
cooler air dominated Chicago's weather scene. Temperatures within a mile of the earth's
surface are so cool, they are to encourage north to northeast winds, predicted to blow
the length of Lake Michigan into the area to tap some lake moisture. It's a development
which could yield some lake-effect sprinkles Thursday night into Friday. Cooling aloft
and an upper disturbance predicted to pass Friday afternoon and night could ignite a
few light showers elsewhere across the metro area.

Six states -- from Minnesota across Iowa, Missouri and eastern Nebraska -- were
under frost and freeze advisories overnight. Breaks in the clouds and lighter winds may
permit 30-degree temperatures and patchy frost in Chicago's far western suburbs.

A low of 3 degrees below zero in snow-covered Fairbanks, Alaska, early Tuesday
marked interior Alaska's earliest sub-zero low since 1988.

OMAR THE STRONGEST LATE SEASON HURRICANE TO HIT THE VIRGIN
ISLANDS IN A DECADE

--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune

Rains predicted to sweep the Chicago area Wednesday into Wednesday night drenched
the Plains on Tuesday. The wet system -- which combines remnant moisture from
Pacific Hurricane Norbert, which roared into Mexico this past weekend, and a fresh
supply of moisture from the Gulf of Mexico -- may produce one-half to 1 inch of rain
here before exiting Thursday. Kansas was hardest hit Tuesday with as much as 2.68
inches recorded near Scott City in southwest Kansas while El Dorado in the center of
the state suffered a 2-inch drenching.

Chilly air -- the coolest here since late May -- spills into the Midwest next. Daytime
highs Thursday and Friday may struggle into the mid-50s. Any clearing at night could
permit local 30s in outlying areas.

FAST INTENSIFYING OMAR THREATENING TO SWEEP PUERTO RICO, VIRGIN
ISLANDS AS A FULL BLOWN HURRICANE

Warm Caribbean waters threaten to turn the season's 15th tropical storm into a
Category-2 hurricane (Sustained winds of 96-110 m.p.h.)as it sweeps toward Puerto
Rico and the Virgin Islands. Hurricane watches have been issued.

--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune

It will seem a lot more like autumn than summer by the end of the week as weather
more typical of mid-October arrives on the scene. Sunday's record-tying highs in the
middle 80s will be long-gone, replaced by Saturday morning lows in the 30s that could
bring frost and even freezing conditions to areas away from Lake Michigan. The
downhill temperature trend will begin slowly on Tuesday and Wednesday as
temperatures remain in the 60s. Cooling gathers steam later in the week as highs fail to
break 60 from Thursday through Saturday.

Some light showers will accompany the first surge of cooler air early Tuesday, but a
more significant shot of rain is expected to move in Wednesday before a stronger
intrusion of colder air.

NANA FADES -- OMAR LIKELY TO BECOME A NAMED STORM TUESDAY

Tropical Storm Nana has weakened to a depression and will dissipate in the open
Atlantic later this week. Meanwhile, another depression gaining strength south of
Puerto Rico should become the season's 15th named storm, Omar, Tuesday. The
system's heavy rains already produced flash flooding in Puerto Rico on Monday.

--By Steve Kahn, WGN Weather Center Meteorologist

For the second straight year the Chicago Marathon was run in unseasonably warm
weather. Sunday's high of 84 degrees at O'Hare Airport tied the day's record high set in
1960, while Midway Airport's 86 equaled a previous 1930 benchmark. In 2007, the race
held on Oct. 7 was canceled after 3.5 hours when the mercury soared to a
record-breaking 87 degrees. The city had not experienced temperatures as high as
Sunday's in more than five weeks since a steamy 94 degrees on Sept. 2.
One more day of warmth is expected Monday, but more cloudiness should temper the
heat, holding readings closer to 80 degrees. More seasonable conditions will return for
the rest of the week as cooler weather moves in following the passage of a cold front
early Tuesday.

IN ATLANTIC, IT'S NANA -- THEN GOODBYE
Tropical Storm Nana, the 14th named storm of the season formed in the open Atlantic
Sunday afternoon about 900 miles west of the Cape Verde Islands. However, Nana is
expected to meet a quick demise as the storm encounters strong winds aloft. In the
Caribbean, forecasters are watching another system south of Puerto Rico that may
strengthen into Tropical Storm Omar.
--By Steve Kahn, WGN Weather Center Meteorologist

It won't be as hot and humid as last year's heat-shortened race, where readings soared
to the middle 80s before noon. But runners competing in Sunday's 31st Chicago
Marathon will still have to contend with late-morning temperatures in the 70s as warm
weather dominates race day for the second straight year. Highs on Sunday should top
out in the lower 80s, compared to last year's record-breaking 87-degree high.

After failing to reach 70 degrees in October's opening nine days for the first time since
1977, the high reached 72 degrees on Friday and 79 Saturday, setting the stage for at
least four straight 70-degree-plus days before the next cooldown arrives Tuesday.
High temperatures should then slowly fall through the 60s the rest of the week as more
seasonable weather returns.

WINTER ARRIVES EARLY IN THE WEST

An early-season storm is bringing the first snows of the season to the northern
portions of the Rockies and High Plains. More than 2 feet of snow has buried portions
of Wyoming and Montana with another foot expected in many areas before the storm
ends. Boise, Idaho received 1.7 inches Friday, its earliest measurable snow since 1898,
when records began there.

--By Steve Kahn, WGN Weather Center Meteorologist

The weather doesn't get much nicer here in October. Chicagoans are in line for a
weekend likely to be the warmest of any until next spring.
Temperatures, which peaked at 72 degrees at O'Hare International Airport on Friday --
the warmest here in 13 days and October's first 70-degree-plus reading -- head even
higher Saturday and Sunday. The mid- and upper 70s predicted in all but immediate
lakeshore locations represent an increase of 16 degrees warmer than last weekend and
run at levels more than 20 degrees warmer than the same period a year ago. While
highs of 75 and 78 degrees are predicted Saturday and Sunday, readings only reached
54 and 59 degrees a year ago.

MONTANA, WYOMING SNOWS ONLY BEGINNING
AND ALREADY UP TO 16" DEEP
The irony of this weekend's exceptional weather is that autumn's most powerful storm
to date is behind the warm south to south winds helping to buoy temperatures.
That system is hammering the West with weather advisories across 13 states. Snowfall
by late Friday had reached 16 inches at Nye, Mont., where wind gusts were clocked at
40 m.p.h.
--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune

The official high temperature at O'Hare missed 70 by just a degree Thursday. It's 31
years since the opening nine days of October have failed to produce a single 70. It's a
string likely to be broken away from Lake Michigan Friday. Though southeast winds off
Lake Michigan are likely to temper lakeside highs, the warmest inland readings should
reach the mid-70s, thanks to an abundance of sun. A series of three additional 70s are
likely to ensue this weekend through Columbus Day, producing the area's longest
70-degree streak this late in the season in eight years. Friday's predicted 72-degree
high is to be the mildest in 13 days.

A powerful storm is pounding the West. Snows may accumulate more than a foot in the
hardest hit locations of Wyoming and Montana while 1-3 inches of rains in sections of
the Dakotas would be the equivalent of two Octobers worth of rain.

HAIL POUNDS SOUTHEAST THURSDAY: CALIFORNIANS WARY OF POWERFUL
WINDS, WILDFIRE THREAT

Nearly 20 reports of hail peppered sections of Georgia, Florida Thursday, including
baseball-size hail at Rochelle, Ga. which damaged automobiles.

--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune

The dry air in place across the Chicago area has cooled overnight, contributing to
Thursday's daybreak chill. Highs Wednesday struggled to reach 64 degrees -- a
situation that is about to change. Areas away from Lake Michigan are in line for a string
of five 70-degree afternoons, which would be the longest late season 70-degree string
in eight years. October's cool open has been unusual and well below the same period a
year ago. The month has failed to produce a 70-degree high to date, something that
has happened here only once in the last half-century.

The warmth predicted in coming days is linked to a buckling jet stream out West
brought on by a southward plunge of cold early season air. The process is to produce a
powerhouse autumn storm that could drench the northern Plains with the equivalent of
two Octobers worth of rain while burying the northern Rockies under as much as 1-2
feet of snow. The system shifts Chicago winds southeast in coming days -- then
southerly over the weekend, promoting warmer and more humid conditions here.

POWERHOUSE PACIFIC HURRICANE NORBERT MAY SEND RAINY REMNANTS
INTO MIDWEST

--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune

Rainfall topped one inch at a number of locations Tuesday, the biggest tallies since
0.82 inches fell at O'Hare International Airport on Sept. 29. The clouds and precipitation
cut deeply into daytime warming, limiting Chicago's high to 63-degrees. The heaviest
preliminary totals at Weather Bug rain gauges in the area included 1.02 inches at
Palatine, 0.89 inches at Oak Lawn, 0.82 inches at Evergreen Park and 1.18 inches at
LaPorte, Ind. COOP Patrick Skach in Oak Brook reported 0.81 inches through 9 p.m. --
and it was still raining. O'Hare's rain tally of 0.54 inches through 8 p.m. pushed the
meteorological autumn tally (since Sept. 1) to 14.24 inches -- the heaviest in 138 years
of official Chicago weather records.

MILD MARATHON AHEAD SUNDAY -- BUT 12 TO 14 DEGREES BELOW A YEAR
AGO

Cold air crashes into the West in coming days setting the stage for big northern
Rockies snows, but warming Chicago into the 70s this weekend. The pattern includes
milder than normal Chicago Marathon weather Sunday -- though cooler than last
year's heat-plagued event which was suspended after 3.5 hours.

--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune

Monday's 69 degrees was Chicago's warmest official high in nine days -- a welcome
development in an October that has averaged nearly 16 degrees cooler than a year ago.
The month's opening six days have been the coolest of any October in four years. The
day's southeasterly winds limited Monday's warmest readings to inland areas. Weather
records suggest it may be three weeks before 70s disappear from the scene here. Over
the last 10 years, Oct. 26 has been the average date of the year's final reading in the
70s -- though a 72-degree high occurred Nov. 18, 1999.

The fall harvest is under way on many area farms, though well behind the five-year
average on a statewide basis. The USDA reported Monday that 10 percent of the state's
corn and 22 percent of its soybeans have been harvested -- well behind the respective
averages of 47 percent and 48 percent over the last five years.

SOUTHBOUND ALASKAN CHILL TO SET STAGE FOR BIG ROCKIES/PLAINS
SNOW

The season's coldest air dropped the temperature at Anaktuvak Pass in Alaska's Brooks
Range to 7 degrees. The southward plunge of that cold air sets the stage for a Rockies
and western Plains snowstorm.

--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune

Chicagoans, it would seem, are growing accustomed to wet weather. The city struggled
through the second-wettest September in 138 years of Chicago weather history, and
computer models now suggest another rainy pattern is establishing itself this week.
Don't expect a repeat of September's deluges, but be advised that rain is mentioned in
Chicago's weather forecasts on five of the next seven days.
Two distinct storm systems head our way this week. The first, the weakened remnant of
a powerful system that blasted into the Pacific Northwest, brings rain to Chicago
Tuesday and Wednesday. Cold air accompanying that system put 10 to 20 inches of
snow across some of the higher mountain elevations of Colorado on Sunday.

WASHOUT NEXT WEEKEND?
Computer models indicate that yet another storm system has Chicago and the Midwest
in its sights toward the weekend, and early indications are that it could be a real
drencher. A strong storm -- slow-moving and dripping with moisture from the Gulf of
Mexico -- is likely to bring rain into the area late Friday, with possibly significant rain
totals occurring on Saturday, Sunday and Monday.
--By Richard Koeneman, WGN Weather Center Meteorologist

A powerhouse storm system, the first major autumn storm of 2008, is barreling from
the Pacific Northwest into the Intermountain Region of the West Sunday. This system
will eventually be a significant player in Chicago’s weather. We’ll experience increasing
southeasterly winds and warmer temperatures starting Sunday. Southeast winds,
though, are lake winds for northern portions of metropolitan Chicago, so the northern
suburbs will experience much less temperature moderation Sunday than western and
southern sections. Rain and thunderstorms will overspread the area from south to north
by early afternoon and continue Sunday night as the western storm system shifts into
the Great Plains. Mild air will arrive in strength Monday and will persist through Tuesday
in advance of the western system.

Looking ahead, rain will push to the east of Chicago by Thursday as cooler, drier air of
Canadian origin arrives, but computer models suggest the cool interlude will be
short-lived. Milder air stages a return on Friday and carries afternoon temperatures into
the 70s by the weekend. It's not even out of the question that Chicago might see
another 80-degree day next Sunday.

Clear skies and light winds under cold high pressure Friday night created near-perfect
radiational cooling conditions.
As a result, early Saturday morning temperatures in the mid to upper 30s and scattered
light frost were expected across northern Illinois. Frost warnings were issued for all of
Wisconsin with early morning readings just north of the Illinois-Wisconsin border
forecast in the lower 30s. East to southeast winds on the backside of cool Canadian
high pressure centered over the northeastern United States will hold over northeast
Illinois this weekend. But as the high slowly loses its grip and moves off the New
England coast, Chicago will experience a gradual moderation of temperatures. Highs on
Saturday will not be that much different than Friday's levels, but Sunday should see the
readings reach the "normal" level (67 degrees) for the first time in a week.

INCREASING TEMPERATURES,
CHANCE OF SHOWERS EARLY NEXT WEEK
As warmer, more moist air approaches from the west, Chicago's early workweek
weather should feature above-normal temperatures and a good chance of showers and
thunderstorms.
--By Paul Dailey, WGN Weather Center Meteorologist

The cool and rather moist air that has bathed the Chicago area in recent days is forecast to yield, albeit slowly, to moderately higher temperatures in the days ahead as the national weather regime shifts gears. For several days, the West has been warm, even hot, and the East has been cool and wet.

That's about to change, and the transition will take place this weekend. Milder air
begins filtering across the Chicago area this weekend, and by Monday the warming
trend is expected to carry temperatures into the 70s.

But there's a complication: Mild air arrives on the wings of brisk southeast winds,
raising the possibility of lake-induced cooling in Chicago's North Shore.

FROST ADVISORIES IN UPPER MIDWEST

National Weather Service offices have posted frost advisories across portions of
Minnesota and Wisconsin for the early-morning hours Friday. Patchy frost is in the
cards again early Saturday morning for much of the Upper Midwest, including northern
Illinois and the typically colder outlying areas of metropolitan Chicago.

--By Richard Koeneman, WGN Weather Center Meteorologist

Chicago’s October temperatures undergo the second-largest monthly decline of the year,
surpassed only by November.

EXTREME MINIMUM SUNSPOT ACTIVITY
Astronomers who keep tabs on sunspots—the dark blotches usually scattered across
the sun’s surface—have observed a recent extreme minimum of sunspot activity.
Sunspots run in 11-year cycles, but the current lull is exceptional (though not without
historical precedent). As of Sept. 27, NASA scientists report that the sun has been
absolutely blank—no sunspots at all—for 200 days in 2008.
NASA’s David Hathaway says, “Sunspot counts are at a 50-year low. We're experiencing
a deep minimum of the solar cycle.” The 11-year solar sunspot cycle is apparently not a
factor in the Earth’s weather because there is no known 11-year-cycle counterpart in
our weather.
--By Richard Koeneman, WGN Weather Center Meteorologist