Winter Storm Warning 2, NWS Chicago, IL

584 
WWUS43 KLOT 240259
WSWLOT

URGENT - WINTER WEATHER MESSAGE
National Weather Service Chicago IL
859 PM CST Sat Dec 23 2017

...Accumulating Snow on Sunday...


INZ001-241100-
/O.CON.KLOT.WS.W.0002.171224T1200Z-171225T0000Z/
Lake IN-
Including the city of Gary
859 PM CST Sat Dec 23 2017

...WINTER STORM WARNING REMAINS IN EFFECT FROM 6 AM TO 6 PM CST
SUNDAY...

* WHAT...Snow, heavy at times. Plan on difficult travel 
  conditions. Total snow accumulations of 4 to 8 inches are 
  expected. Totals over 6 inches may be isolated and occur closer 
  to Lake Michigan.

* WHERE...Lake County, Indiana.

* WHEN...From 6 AM to 6 PM CST Sunday.

* ADDITIONAL DETAILS...Be prepared for significant reductions in 
  visibility at times, possibly below one half mile. Lake 
  enhancement may result in a band of very intense snowfall 
  within a larger area of less intense snowfall. This may lead 
  to accumulation rates of around 1 inch per hour. This heavier 
  band may be transient and only occur for a short time over a 
  given area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow means severe winter weather
conditions are expected. If you must travel, keep an extra
flashlight, food and water in your vehicle in case of an
emergency.

$$

INZ002-241100-
/O.CON.KLOT.WS.W.0002.171224T1200Z-171225T0300Z/
Porter-
Including the city of Valparaiso
859 PM CST Sat Dec 23 2017

...WINTER STORM WARNING REMAINS IN EFFECT FROM 6 AM TO 9 PM CST
SUNDAY...

* WHAT...Snow, heavy at times. Plan on difficult travel 
  conditions. Total snow accumulations of 4 to 8 inches are 
  expected. Totals over 6 inches may be isolated and occur closer 
  to Lake Michigan.

* WHERE...Porter County.

* WHEN...From 6 AM to 9 PM CST Sunday.

* ADDITIONAL DETAILS...Be prepared for significant reductions in 
  visibility at times, possibly below one half mile. Lake 
  enhancement may result in a band of very intense snowfall 
  within a larger area of less intense snowfall. This may lead 
  to accumulation rates of around 1 inch per hour. This heavier 
  band may be transient and only occur for a short time over a 
  given area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow means severe winter weather
conditions are expected. If you must travel, keep an extra
flashlight, food and water in your vehicle in case of an
emergency. 

$$

ILZ023-241100-
/O.EXT.KLOT.WW.Y.0003.171224T1200Z-171225T0000Z/
Kankakee-
Including the city of Kankakee
859 PM CST Sat Dec 23 2017

...WINTER WEATHER ADVISORY NOW IN EFFECT FROM 6 AM TO 6 PM CST
SUNDAY...

* WHAT...Snow, moderate at times. Plan on difficult travel 
  conditions. Total snow accumulations of 3 to 5 inches are 
  expected. Isolated totals of 6 inches are possible.

* WHERE...Portions of east central Illinois.

* WHEN...From 6 AM to 6 PM CST Sunday.

* ADDITIONAL DETAILS...Bursts of more intense snow may occur at 
  times leading to accumulation rates over one half inch per 
  hour and visibility under one mile.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow means periods of snow will
cause primarily travel difficulties. Be prepared for snow covered
roads and limited visibilities, and use caution while driving.

$$

ILZ012>014-241100-
/O.CON.KLOT.WW.Y.0003.171224T1200Z-171225T0000Z/
Kane-DuPage-Cook-
Including the cities of Aurora, Elgin, Wheaton, and Chicago
859 PM CST Sat Dec 23 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 AM TO 6 PM
CST SUNDAY...

* WHAT...Snow, moderate at times. Plan on slippery road 
  conditions. Total snow accumulations of 2 inches north to 4 
  inches south are expected.

* WHERE...Kane, DuPage and Cook Counties.

* WHEN...From 6 AM to 6 PM CST Sunday.

* ADDITIONAL DETAILS...Bursts of more intense snow may occur at
  times leading to accumulation rates over one half inch per hour
  and visibility under one mile. Be prepared for reduced 
  visibilities at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow means periods of snow will
cause primarily travel difficulties. Be prepared for snow covered
roads and limited visibilities, and use caution while driving.

$$

ILZ010-011-019>021-032-033-039-241100-
/O.CON.KLOT.WW.Y.0003.171224T1000Z-171225T0000Z/
Lee-DeKalb-La Salle-Kendall-Grundy-Livingston-Iroquois-Ford-
Including the cities of Dixon, DeKalb, Ottawa, Oswego, Morris, 
Pontiac, Watseka, and Paxton
859 PM CST Sat Dec 23 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 4 AM TO 6 PM
CST SUNDAY...

* WHAT...Snow, moderate at times. Plan on difficult travel
  conditions. Total snow accumulations of 3 to 5 inches are
  expected. Isolated totals of 6 inches are possible.

* WHERE...Portions of northern Illinois, mainly along and south 
  of Interstate 88.

* WHEN...From 4 AM to 6 PM CST Sunday.

* ADDITIONAL DETAILS...Bursts of more intense snow may occur at 
  times leading to accumulation rates over one half inch per 
  hour and visibility under one mile.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow means periods of snow will
cause primarily travel difficulties. Be prepared for snow covered
roads and limited visibilities, and use caution while driving.

$$

ILZ022-INZ010-011-019-241100-
/O.CON.KLOT.WW.Y.0003.171224T1200Z-171225T0000Z/
Will-Newton-Jasper-Benton-
Including the cities of Joliet, Morocco, Rensselaer, and Fowler
859 PM CST Sat Dec 23 2017 /959 PM EST Sat Dec 23 2017/

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 AM CST /7 AM
EST/ TO 6 PM CST /7 PM EST/ SUNDAY...

* WHAT...Snow, moderate at times. Plan on difficult travel 
  conditions. Total snow accumulations of 3 to 5 inches are 
  expected. Isolated totals of 6 inches are possible, especially 
  in Indiana.

* WHERE...In Indiana, Newton, Jasper and Benton Counties. In 
  Illinois, Will County.

* WHEN...From 6 AM CST /7 AM EST/ to 6 PM CST /7 PM EST/ Sunday.

* ADDITIONAL DETAILS...Bursts of more intense snow may occur at 
  times leading to accumulation rates over one half inch per 
  hour and visibility under one mile.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow means periods of snow will
cause primarily travel difficulties. Be prepared for snow covered
roads and limited visibilities, and use caution while driving.

$$

942 
WWUS43 KLOT 240932
WSWLOT

URGENT - WINTER WEATHER MESSAGE
National Weather Service Chicago IL
332 AM CST Sun Dec 24 2017

...Accumulating Snow on Sunday...

INZ001-241745-
/O.CON.KLOT.WS.W.0002.171224T1200Z-171225T0000Z/
Lake IN-
332 AM CST Sun Dec 24 2017

...WINTER STORM WARNING REMAINS IN EFFECT FROM 6 AM THIS MORNING
TO 6 PM CST THIS EVENING...

* WHAT...Snow, heavy at times. Plan on difficult travel 
  conditions. Total snow accumulations of 4 to 7 inches are 
  expected.

* WHERE...Lake IN County.

* WHEN...From 6 AM this morning to 6 PM CST this evening.

* ADDITIONAL DETAILS...Be prepared for significant reductions in 
  visibility at times, possibly below one half mile. Lake 
  enhancement may result in a band of very intense snowfall 
  within a larger area of less intense snowfall. This may lead 
  to accumulation rates of around 1 inch per hour. This heavier 
  band may be transient and only occur for a short time over a 
  given area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow means severe winter weather
conditions are expected. If you must travel, keep an extra
flashlight, food and water in your vehicle in case of an
emergency.

$$

INZ002-241745-
/O.CON.KLOT.WS.W.0002.171224T1200Z-171225T0300Z/
Porter-
332 AM CST Sun Dec 24 2017

...WINTER STORM WARNING REMAINS IN EFFECT FROM 6 AM THIS MORNING
TO 9 PM CST THIS EVENING...

* WHAT...Snow, heavy at times. Plan on difficult travel 
  conditions. Total snow accumulations of 4 to 7 inches are 
  expected.

* WHERE...Porter County.

* WHEN...From 6 AM this morning to 9 PM CST this evening.

* ADDITIONAL DETAILS...Be prepared for significant reductions in 
  visibility at times, possibly below one half mile. Lake 
  enhancement may result in a band of very intense snowfall 
  within a larger area of less intense snowfall. This may lead 
  to accumulation rates of around 1 inch per hour. This heavier 
  band may be transient and only occur for a short time over a 
  given area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow means severe winter weather
conditions are expected. If you must travel, keep an extra
flashlight, food and water in your vehicle in case of an
emergency. 

$$

ILZ012>014-241745-
/O.CON.KLOT.WW.Y.0003.171224T1200Z-171225T0000Z/
Kane-DuPage-Cook-
332 AM CST Sun Dec 24 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 AM THIS
MORNING TO 6 PM CST THIS EVENING...

* WHAT...Snow expected. Plan on slippery road conditions. Total 
  snow accumulations of 2 to 4 inches are expected.

* WHERE...Kane, DuPage and Cook Counties.

* WHEN...From 6 AM this morning to 6 PM CST this evening.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at
  times. Snowfall rates may reach one half inch per hour mid
  morning throug early afternoon. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow means periods of snow will
cause primarily travel difficulties. Be prepared for snow covered
roads and limited visibilities, and use caution while driving.

$$

ILZ010-011-019>021-032-033-039-241745-
/O.CON.KLOT.WW.Y.0003.171224T1000Z-171225T0000Z/
Lee-De Kalb-La Salle-Kendall-Grundy-Livingston-Iroquois-Ford-
332 AM CST Sun Dec 24 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 6 PM CST THIS
EVENING...

* WHAT...Snow expected. Plan on slippery road conditions. Total 
  snow accumulations of 3 to 5 inches are expected.

* WHERE...Portions of central, east central, north central and 
  northeast Illinois.

* WHEN...Until 6 PM CST this evening.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at
  times. Snowfall rates may reach up to 1 inch per hour through
  early to mid afternoon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow means periods of snow will
cause primarily travel difficulties. Be prepared for snow covered
roads and limited visibilities, and use caution while driving.

$$

ILZ022-023-INZ010-011-019-241745-
/O.CON.KLOT.WW.Y.0003.171224T1200Z-171225T0000Z/
Will-Kankakee-Newton-Jasper-Benton-
332 AM CST Sun Dec 24 2017 /432 AM EST Sun Dec 24 2017/

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 AM CST /7 AM
EST/ THIS MORNING TO 6 PM CST /7 PM EST/ THIS EVENING...

* WHAT...Snow expected. Plan on difficult travel conditions. Total
  snow accumulations of 3 to 6 inches are expected.

* WHERE...In Indiana, Newton, Jasper and Benton Counties. In 
  Illinois, Will and Kankakee Counties.

* WHEN...From 6 AM CST /7 AM EST/ this morning to 6 PM CST /7 PM 
  EST/ this evening.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at 
  times. Bursts of more intense snow may occur at 
  times leading to accumulation rates over one half inch per 
  hour and visibility under one mile.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow means periods of snow will
cause primarily travel difficulties. Be prepared for snow covered
roads and limited visibilities, and use caution while driving.

$$

790 
WWUS43 KLOT 241654
WSWLOT

URGENT - WINTER WEATHER MESSAGE
National Weather Service Chicago IL
1054 AM CST Sun Dec 24 2017

...Accumulating Snow on Sunday...

INZ001-250000-
/O.CON.KLOT.WS.W.0002.000000T0000Z-171225T0000Z/
Lake IN-
Including the city of Gary
1054 AM CST Sun Dec 24 2017

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM CST THIS
EVENING...

* WHAT...Snow occurring, heavy at times. Plan on difficult travel
  conditions. Total snow accumulations of 4 to 7 inches are 
  expected.

* WHERE...Lake County IN.

* WHEN...Until 6 PM CST this evening.

* ADDITIONAL DETAILS...Be prepared for significant reductions in 
  visibility at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow means severe winter weather
conditions are occurring. If you must travel, keep an extra
flashlight, food and water in your vehicle in case of an
emergency. The latest road conditions for the state you are
calling from can be obtained by calling 5 1 1.

$$

INZ002-250100-
/O.CON.KLOT.WS.W.0002.000000T0000Z-171225T0300Z/
Porter-
Including the city of Valparaiso
1054 AM CST Sun Dec 24 2017

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 9 PM CST THIS
EVENING...

* WHAT...Snow occurring, heavy at times. Plan on difficult travel
  conditions. Total snow accumulations of 4 to 8 inches are 
  expected.

* WHERE...Porter County.

* WHEN...Until 9 PM CST this evening.

* ADDITIONAL DETAILS...Be prepared for significant reductions in 
  visibility at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow means severe winter weather
conditions are occurring. If you must travel, keep an extra
flashlight, food and water in your vehicle in case of an
emergency. The latest road conditions for the state you are
calling from can be obtained by calling 5 1 1.

$$

ILZ012>014-250000-
/O.CON.KLOT.WW.Y.0003.000000T0000Z-171225T0000Z/
Kane-DuPage-Cook-
Including the cities of Aurora, Elgin, Wheaton, and Chicago
1054 AM CST Sun Dec 24 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 6 PM CST THIS
EVENING...

* WHAT...Snow occurring. Plan on slippery road conditions. Total 
  snow accumulations of 2 to 5 inches are expected, highest along 
  and near the Cook County shore.

* WHERE...Kane, DuPage and Cook Counties.

* WHEN...Until 6 PM CST this evening.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at 
  times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow means periods of snow will
cause primarily travel difficulties. Be prepared for snow covered
roads and limited visibilities, and use caution while driving.
The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

$$

ILZ010-011-019>021-032-033-039-250000-
/O.CON.KLOT.WW.Y.0003.000000T0000Z-171225T0000Z/
Lee-DeKalb-La Salle-Kendall-Grundy-Livingston-Iroquois-Ford-
Including the cities of Dixon, DeKalb, Ottawa, Oswego, Morris, 
Pontiac, Watseka, and Paxton
1054 AM CST Sun Dec 24 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 6 PM CST THIS
EVENING...

* WHAT...Snow occurring. Plan on slippery road conditions. Total 
  snow accumulations of 3 to 6 inches are expected.

* WHERE...Portions of central, east central, north central and 
  northeast Illinois.

* WHEN...Until 6 PM CST this evening.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at 
  times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow means periods of snow will
cause primarily travel difficulties. Be prepared for snow covered
roads and limited visibilities, and use caution while driving.
The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

$$

ILZ022-023-INZ010-011-019-250000-
/O.CON.KLOT.WW.Y.0003.000000T0000Z-171225T0000Z/
Will-Kankakee-Newton-Jasper-Benton-
Including the cities of Joliet, Kankakee, Morocco, Rensselaer, 
and Fowler
1054 AM CST Sun Dec 24 2017 /1154 AM EST Sun Dec 24 2017/

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 6 PM CST /7 PM
EST/ THIS EVENING...

* WHAT...Snow occurring. Plan on difficult travel conditions.
  Total snow accumulations of 3 to 6 inches are expected.

* WHERE...In Indiana, Newton, Jasper and Benton Counties. In 
  Illinois, Will and Kankakee Counties.

* WHEN...Until 6 PM CST /7 PM EST/ this evening.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at 
  times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow means periods of snow will
cause primarily travel difficulties. Be prepared for snow covered
roads and limited visibilities, and use caution while driving.
The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

$$

294 
WWUS43 KLOT 242125
WSWLOT

URGENT - WINTER WEATHER MESSAGE
National Weather Service Chicago IL
325 PM CST Sun Dec 24 2017

...Accumulating Snow on Sunday...

INZ001-250000-
/O.CON.KLOT.WS.W.0002.000000T0000Z-171225T0000Z/
Lake IN-
Including the city of Gary
325 PM CST Sun Dec 24 2017

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM CST THIS
EVENING...

* WHAT...Snow occurring, heavy at times. Plan on difficult travel 
  conditions. Additional snow accumulations of up to two inches 
  are expected.

* WHERE...Lake County IN.

* WHEN...Until 6 PM CST this evening.

* ADDITIONAL DETAILS...Be prepared for significant reductions in 
  visibility at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow means severe winter weather
conditions are occurring. If you must travel, keep an extra
flashlight, food and water in your vehicle in case of an
emergency. The latest road conditions for the state you are
calling from can be obtained by calling 5 1 1.

$$

INZ002-250300-
/O.CON.KLOT.WS.W.0002.000000T0000Z-171225T0300Z/
Porter-
Including the city of Valparaiso
325 PM CST Sun Dec 24 2017

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 9 PM CST THIS
EVENING...

* WHAT...Snow occurring, heavy at times. Plan on difficult travel 
  conditions. Additional snow accumulations of 2 to 4 inches are 
  expected.

* WHERE...Porter County.

* WHEN...Until 9 PM CST this evening.

* ADDITIONAL DETAILS...Be prepared for significant reductions in 
  visibility at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow means severe winter weather
conditions are occurring. If you must travel, keep an extra
flashlight, food and water in your vehicle in case of an
emergency. The latest road conditions for the state you are
calling from can be obtained by calling 5 1 1.

$$

ILZ012>014-250000-
/O.CON.KLOT.WW.Y.0003.000000T0000Z-171225T0000Z/
Kane-DuPage-Cook-
Including the cities of Aurora, Elgin, Wheaton, and Chicago
325 PM CST Sun Dec 24 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 6 PM CST THIS
EVENING...

* WHAT...Snow diminishing. Plan on slippery road conditions. 
  Additional snow accumulation under one inch.

* WHERE...Kane, DuPage and Cook Counties.

* WHEN...Until 6 PM CST this evening.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at 
  times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow means periods of snow will
cause primarily travel difficulties. Be prepared for snow covered
roads and limited visibilities, and use caution while driving.
The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

$$

ILZ010-011-019>021-032-033-039-250000-
/O.CON.KLOT.WW.Y.0003.000000T0000Z-171225T0000Z/
Lee-DeKalb-La Salle-Kendall-Grundy-Livingston-Iroquois-Ford-
Including the cities of Dixon, DeKalb, Ottawa, Oswego, Morris, 
Pontiac, Watseka, and Paxton
325 PM CST Sun Dec 24 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 6 PM CST THIS
EVENING...

* WHAT...Snow occurring. Plan on slippery road conditions. 
  Additional snow accumulation generally under one inch.

* WHERE...Portions of central, east central, north central and 
  northeast Illinois.

* WHEN...Until 6 PM CST this evening.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at 
  times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow means periods of snow will
cause primarily travel difficulties. Be prepared for snow covered
roads and limited visibilities, and use caution while driving.
The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

$$

ILZ022-023-INZ010-011-019-250000-
/O.CON.KLOT.WW.Y.0003.000000T0000Z-171225T0000Z/
Will-Kankakee-Newton-Jasper-Benton-
Including the cities of Joliet, Kankakee, Morocco, Rensselaer, 
and Fowler
325 PM CST Sun Dec 24 2017 /425 PM EST Sun Dec 24 2017/

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 6 PM CST /7 PM
EST/ THIS EVENING...

* WHAT...Snow occurring. Plan on slippery road conditions. 
  Additional snow accumulation of up to one inch.

* WHERE...In Indiana, Newton, Jasper and Benton Counties. In 
  Illinois, Will and Kankakee Counties.

* WHEN...Until 6 PM CST /7 PM EST/ this evening.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at 
  times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow means periods of snow will
cause primarily travel difficulties. Be prepared for snow covered
roads and limited visibilities, and use caution while driving.
The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

$$

309 
WWUS43 KLOT 250007
WSWLOT

URGENT - WINTER WEATHER MESSAGE
National Weather Service Chicago IL
607 PM CST Sun Dec 24 2017

INZ001-250115-
/O.EXP.KLOT.WS.W.0002.000000T0000Z-171225T0000Z/
Lake IN-
Including the city of Gary
607 PM CST Sun Dec 24 2017

...WINTER STORM WARNING HAS EXPIRED...

Very light snow and flurries are possible this evening but no
additional accumulation is expected.

$$

ILZ010>014-019>023-032-033-039-INZ010-011-019-250115-
/O.EXP.KLOT.WW.Y.0003.000000T0000Z-171225T0000Z/
Lee-DeKalb-Kane-DuPage-Cook-La Salle-Kendall-Grundy-Will-Kankakee-
Livingston-Iroquois-Ford-Newton-Jasper-Benton-
Including the cities of Dixon, DeKalb, Aurora, Elgin, Wheaton, 
Chicago, Ottawa, Oswego, Morris, Joliet, Kankakee, Pontiac, 
Watseka, Paxton, Morocco, Rensselaer, and Fowler
607 PM CST Sun Dec 24 2017 /707 PM EST Sun Dec 24 2017/

...WINTER WEATHER ADVISORY HAS EXPIRED...

Very light snow and flurries are possible this evening but no
additional accumulation is expected.

$$

INZ002-250300-
/O.CON.KLOT.WS.W.0002.000000T0000Z-171225T0300Z/
Porter-
Including the city of Valparaiso
607 PM CST Sun Dec 24 2017

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 9 PM CST THIS
EVENING...

* WHAT...Snow, heavy at times. Plan on difficult travel 
  conditions. Additional snow accumulations of up to one inch are 
  expected.

* WHERE...Porter County.

* WHEN...Until 9 PM CST this evening.

* ADDITIONAL DETAILS...Be prepared for significant reductions in 
  visibility at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow means severe winter weather
conditions are occurring. If you must travel, keep an extra
flashlight, food and water in your vehicle in case of an
emergency.

$$

300 
WWUS43 KLOT 250236
WSWLOT

URGENT - WINTER WEATHER MESSAGE
National Weather Service Chicago IL
836 PM CST Sun Dec 24 2017

INZ002-250345-
/O.EXP.KLOT.WS.W.0002.000000T0000Z-171225T0300Z/
Porter-
Including the city of Valparaiso
836 PM CST Sun Dec 24 2017

...WINTER STORM WARNING WILL EXPIRE AT 9 PM CST THIS EVENING...

Light snow will taper to occasional flurries. No significant
additional accumulation is expected.

$$

Izzi

Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
1203 PM CST Sat Dec 23 2017

.UPDATE...
1107 AM CST

Focus continues to be on snow arriving Sunday morning and
continuing through the day. Previous discussion outlines things
well and remains valid though there are some growing concerns
looking through the latest trends and forecast data this morning.
The primary concern is potential for lake enhancement or even a
band of lake effect snow working in conjunction with the larger
scale forcing across parts of Northwest Indiana. Expected lake
effect thermodynamic parameters are sufficient by Sunday morning.
Winds will be northerly as the main surface low develops well to
the south and high pressure departs to the east. However, a
weakness in the pressure field between the two may allow for a
more focused lake convergent trough to develop. Some of the higher
resolution guidance does depict this. This results in growing
concern for bands of higher accumulation rate snow to occur in
parts of Lake and Porter County Indiana from mid morning into
early afternoon. These details are still not clear at this time
range but the signal for periods of high snowfall accumulation
rates and very low visibility, along with the potential for at
least isolated snowfall totals of 6 inches or slightly higher is
greater than it was earlier. Will begin to better emphasize this
potential and resultant travel concerns through this corridor and
will also be considering a Winter Storm Warning, but will make no
changes to headlines at this point as confidence in occurrence is
not great.

Further inland across areas from Kankakee to Gibson City eastward
into Northwest Indiana outside of Lake/Porter, continue to see
signals for a deep snow growth zone and occurrence of stronger
forced bands of snow within the larger area of lighter snow.
Banding potential will bring about somewhat higher accumulation
rates at times which may lead to totals into the 5 to 6 inch range
in spots. Not planning any changes to the advisory at this time.

MDB

&&

.SHORT TERM...
308 AM CST

Through Sunday...

Concerns center on accumulating snowfall on Sunday, focusing on
locations of highest snow.

First on the docket before the snow for Christmas Eve is a band of
precipitation out ahead of a stronger wave across the lower
Missouri valley. There still appears to be a sharp cutoff in
precipitation as colder and drier air across our area continues to
push into the axis of precipitation. While it has been rain to our
south, forecast profiles suggest the dominant type would snow
overnight. At this time the window for snow would be short and
marginal temperatures suggest little accumulation. Otherwise today
there will be some continued erosion to the low clouds across the
area. Therefore we will see come clearing outside of the
departing higher clouds and additional mid and high cloud arrival
later today. Cold advection will still hold temperatures down a
few degrees above or below the freezing mark, but all in all not a
bad day.

There is remarkably good agreement amongst the 0z suite of models
regarding the timing of a developing band of snow on Christmas
Eve, with peak snows around daybreak until mid to late afternoon.
The wave that will go on to create our accumulating snowfall is
up near Puget Sound in the Pacific Northwest.

There is also very good agreement on there being a
stripe of heavier snow in this snow band, with the higher QPF
numbers approaching 0.2" or a little more. While the omega
(forcing as a result of warm advection and vorticity/QG advection)
is not off the charts, which is consistent with a lower amplitude
system, forecast soundings continue to feature a fairly deep
dendritic growth layer where this omega is focused for more
optimal/higher snow ratio type snow in this pattern. Therefore
these QPF numbers could easily result in an axis of 2-4" of snow
(locally higher downwind of Lake Michigan in NW Indiana) especially
in areas where the system slows/pivots. The snow ratios will be
still be fairly high around it, but with lower QPF slightly lower
numbers around it. So even though the GEFS ensemble/SREF means for
Chicago Ohare is 0.1", and 0.12" QPF, this could still produce up
to 2" given the current model track. Subtle shifts would result
in more if it shifts north, and a bit less if it goes south. Have
not seen a northward shift with these model runs. At this point
it appears most locations will at least see some accumulation,
with north central IL having the lowest chances.

Regarding timing for holiday travel, ensemble probabilities
highlight a 8 am to 3pm time frame with potential for 0.25" to
0.5" per hour type snow rates. While some waffling is still
expected, the best agreement in this heavier axis still appears to
be a Pontiac northeast to Chicago line, with the longer residence
time focused on a Kankakee to Valpo axis.

These types of numbers and rates in conjunction with lack of
accumulating snow thus far and the increased holiday travel
warrants an advisory, but the challenge given the system
waffling, and developing just upstream of the area, suggest that
this axis could still vary. But given the preponderance of the
current evidence, will issue an advisory for the aforementioned
higher axis where there is better model agreement. Dupage and
Cook (especially northern Cook) are on the fringes of the higher
snow numbers (given the current forecast track), and so will give
the day shift a chance to peek at the 12z runs and see if the EC's
northern track bears fruit. We still have some time given that
snow in Chicago is still a bit more than 24 hours out. Overall
totals across much of the area look like they would range from
0.5" near Wisconsin to 4" closer to central Illinois and into
northwest Indiana.

The good news for anyone traveling in the evening, snows will end
outside of the I-80/90/94 corridor in NW Indiana into SE Michigan.

KMD

&&

.LONG TERM...
308 AM CST

Sunday through Friday...

Winter cold will arrive for much of the week, with very cold
temperatures Tuesday and Wednesday.

We return to the the lower amplitude northwest flow pattern
through mid week, and timing the individual wave strength and
location with the uncertainty in waves lending to some lower
confidence in snow chances this week, and outlined in an earlier
evening graphic on our social media and website). The first of
these waves may result in a wave of snow Tuesday, though much of
the guidance is generally dry through Wednesday night. What is of
fairly high confidence is that following our shot of snow, some
bitterly cold air will arrive, with the peak of the cold centered
on Tuesday and Wednesday. GFS ensemble plumes hold highs in the
teens (mean is 11F and 15F at ORD for Tues/Weds respectively).
Specific highs are lower confidence, but high confidence exists
for single digits wind chills Christmas morning, and below zero
wind chills Tuesday and Wednesday morning, with Tuesday having
wind chills staying only in the single digits, possibly only
reaching the zero mark in the north.

Another series of waves arrives later in the week, but confidence
on specifics remains low for more than chance of snow each day
late in the week. Some recovery in temps will occur during the
remainder of the work week, with another bitter cold shot possible
for the weekend.

KMD

&&

.AVIATION...
For the 18Z TAFs...

The main concern will be snow and IFR or even some LIFR conditions
Sunday. For the rest of today, northwest winds will continue but
become light and variable later this evening. Satellite shows a
band of sct-bkn MVFR clouds moving eastward into the terminals.
Cigs should lift as these clouds move into the Chicago area but
some intermittent MVFR is possible into mid afternoon. Otherwise,
cigs will lower overnight and light snow will spread in. The
system will be developing/intensifying as it crosses the area
through the day Sunday. RFD will see the least snow but some brief
IFR snow is possible. ORD/MDW/DPA will likely see steadier snow
and there is the potential for stronger bands of snow to
occasionally occur bring vsby down to less that 1SM for brief
periods. These bands would also bring snow accumulation rates in
the 0.5 to 0.75 in/hr range for at least brief periods. Snow will
end from west to east very late in the afternoon. GYY will also
see steady snow through the day but have a chance to see some lake
enhanced snow as well. Am concerned that a more intense band of
snow may set up and at least be near the airport at some point
from late morning into early afternoon. If this does develop, and
it is not clear that it will, 1/4-1/2SM vsby and quick
accumulations may occur at times.

MDB

&&

.MARINE...
325 AM CST

Only change to the going headline is to extend the Small Craft
Advisory into this evening for the Indiana nearshore waters.
Persistent, brisk nwly winds should keep 4 to 6 foot waves going a
bit longer, especially for locations east of Gary.

Otherwise, the next concern for Lake Michigan will be the onset of
west to northwest Gales late Sunday night into Monday. The models
have been a bit inconsistent on wind speeds following the passage
of an arctic cold front by early Monday morning. The latest
guidance has gone back to indicating gale force winds in an area
of strong cold advection and pressure rises following the passage
of the frontal trough and high pressure building across the upper
Mississippi Valley. Confidence is a little higher on the other
hazard, being freezing spray. With a very cold air mass
overspreading the lake and with lake water temperatures still in
the upper 30s, near-gale force winds will be sufficient to
generate moderate freezing spray. By Tuesday evening, the ridge
will build across Lake Michigan, allowing winds to diminish and
ending the threat for freezing spray.

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...Winter Weather Advisory...ILZ019-ILZ020-ILZ021-ILZ023-ILZ032-
     ILZ033-ILZ039...4 AM Sunday to 6 PM Sunday.

     Winter Weather Advisory...ILZ022...6 AM Sunday to 6 PM Sunday.

IN...Winter Weather Advisory...INZ001-INZ002-INZ010-INZ011-INZ019...6
     AM Sunday to 6 PM Sunday.

LM...Small Craft Advisory...IN nearshore waters until 10 PM Saturday.

&&

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Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
313 AM CST Sat Dec 23 2017

ILZ003>006-008-010>014-019>023-032-033-039-INZ001-002-010-011-019-
241200-
Winnebago-Boone-McHenry-Lake Illinois-Ogle-Lee-De Kalb-Kane-
DuPage-Cook-La Salle-Kendall-Grundy-Will-Kankakee-Livingston-
Iroquois-Ford-Lake Indiana-Porter-Newton-Jasper-Benton-
313 AM CST Sat Dec 23 2017 /413 AM EST Sat Dec 23 2017/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL ILLINOIS...
NORTHEAST ILLINOIS AND NORTHWEST INDIANA.

.DAY ONE...Today and Tonight.

WEATHER HAZARDS EXPECTED:

  Limited Snow Risk far southeast early this morning and again
southwest late tonight.

DISCUSSION:

A band of snow will shift into east central Illinois and northwest
Indiana. While heavier snows are expected south of the area, some
light snow may enter a few counties across these areas. Snow will
arrive from the west across Lasalle, Livingston, and possibly a few
other adjacent counties late tonight.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

Sunday...
  Elevated Snow Risk.
Monday through Wednesday...
  Elevated Excessive Cold Risk.
Thursday and Friday...
  Limited Excessive Cold Risk.

DISCUSSION:

A band of accumulating snow will shift into northeast Illinois
and northwest Indiana, with the more moderate intensity snowfall
expected between 8 am and 3 pm. Snowfall rates up to a half inch
per hour are possible for a few hours, with quarter inch per
hour rates more common outside of the heavier band. At this point areas
along and southeast of a Pontiac to Chicago line are favored for
more accumulation, but areas north to the Wisconsin border may
still see some accumulating snow. Small shifts in the storm
track will affect totals. Most of the snow will end by sunset,
maybe lasting a tad longer across northwest Indiana.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be necessary through tonight.

&&

LMZ740>745-241200-
Winthrop Harbor to Wilmette Harbor-
Wilmette Harbor to Northerly Island-
Northerly Island to Calumet Harbor-Calumet Harbor to Gary-
Gary to Burns Harbor-Burns Harbor to Michigan City-
313 AM CST Sat Dec 23 2017

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE ILLINOIS NEARSHORE
WATERS OF LAKE MICHIGAN AND THE INDIANA NEARSHORE WATERS OF LAKE
MICHIGAN.

.DAY ONE...Today and tonight.

  No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

Sunday through Tuesday...
  Hazardous Conditions for Small Craft are likely.

&&

LMZ080-261-362-364-366-563-565-567-669-671-673-675-777-779-868-
870-872-874-876-878-241200-
Lake Michigan from Michigan City IN to St. Joseph MI 5 NM
offshore to Mid Lake-
Lake Michigan from Seul Choix Point to Rock Island Passage 5 NM
offshore to Mid Lake-
Lake Michigan South of a line from Seul Choix Point to the
Mackinac Bridge and north of a line from Charlevoix MI to South
Fox Island 5 NM offshore-
Lake Michigan from Charlevoix to Point Betsie MI 5 NM offshore to
Mid Lake-
Lake Michigan from Point Betsie to Manistee MI 5 NM offshore to
Mid Lake-
Lake Michigan from Rock Island Passage to Sturgeon Bay WI-
Lake Michigan from Sturgeon Bay to Two Rivers WI 5 NM offshore to
Mid Lake-
Lake Michigan from Two Rivers to Sheboygan WI 5 NM offshore to
Mid Lake-
Lake Michigan from Sheboygan to Port Washington WI 5 NM offshore
to Mid Lake-
Lake Michigan from Port Washington to North Point Light WI 5 NM
offshore to Mid Lake-
Lake Michigan from North Point Light to Wind Point WI 5 NM
offshore to Mid Lake-
Lake Michigan from Wind Point WI to Winthrop Harbor IL 5 NM
offshore to Mid Lake-
Lake Michigan from Winthrop Harbor to Wilmette Harbor IL 5 NM
offshore to Mid Lake-
Lake Michigan from Wilmette Harbor IL to Michigan City IN 5 NM
offshore to Mid Lake-
Lake Michigan from Pentwater to Manistee MI 5 NM offshore to Mid
Lake-
Lake Michigan from Whitehall to Pentwater MI 5 NM offshore to Mid
Lake-
Lake Michigan from Grand Haven to Whitehall MI 5 NM offshore to
Mid Lake-
Lake Michigan from Holland to Grand Haven MI 5 NM offshore to Mid
Lake-
Lake Michigan from South Haven to Holland MI 5 NM offshore to Mid
Lake-
Lake Michigan from St. Joseph to South Haven MI 5 NM offshore to
Mid Lake-
313 AM CST Sat Dec 23 2017

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE OPEN WATERS OF LAKE
MICHIGAN.

.DAY ONE...Today and tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

Gale force winds and freezing spray are likely Monday.

&&

KMD

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