Area Forecast Discussion
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FXUS63 KLOT 311003 AAA
AFDLOT

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
403 AM CST SAT JAN 31 2015

.SHORT TERM...
348 AM CST

THROUGH SUNDAY NIGHT...

SIGNIFICANT WINTER STORM STILL POISED TO AFFECT THE AREA STARTING
TONIGHT AND CONTINUING THROUGH SUNDAY EVENING.

HEADLINES...
HAVE GONE AHEAD AND UPGRADED THE ENTIRE CWA TO A WINTER STORM
WARNING FOR LATE THIS EVENING THROUGH SUNDAY EVENING. FOR SIMPLICITY
SAKE...HAVE GONE WITH SAME START AND END TIME ACROSS THE CWA...AN
ARGUMENT COULD HAVE BEEN MADE TO START LATER IN SOUTHERN CWA AND
AREAS NEAR THE LAKE COULD NEED TO BE EXTENDED A BIT IF LAKE EFFECT
IS MORE IMPRESSIVE THAN EXPECTED...BUT GENERALLY THINK THAT 03Z THIS
EVENING THROUGH 03Z SUNDAY EVENING WILL COVER THE MEAT AND POTATOES
OF THE EVENT MOST AREAS.

SYNOPTICS/MODELS ANALYSIS...
STILL LOOKING A FAIRLY COMPLEX EVOLUTION OF PATTERN THE NEXT COUPLE
OF DAYS AS VIGOROUS SHORTWAVE OVER ALBERTA IS FORECAST TO DIG
SOUTHEAST INTO THE NORTHERN AND CENTRAL ROCKIES AS STRONG CLOSED LOW
OVER THE SOUTHWEST DROPS SOUTH AND BECOMES INCREASINGLY CUT OFF FROM
BELT OF WESTERLIES. FARTHER NORTH A STRONG SHORTWAVE PIVOTING AROUND
HUDSON LOW WILL HELP DRIVE A COLD FRONT SOUTH INTO NORTHERN ILLINOIS
THIS EVENING WITH THE FRONT STALLING OUT. AS STRONG ALBERTA CLIPPER
DROPS SOUTH INTO THE ROCKIES LOOK FOR CYCLOGENESIS TO OCCUR OVER
COLORADO TODAY...THEN TRACK EAST TOWARD THE OHIO VALLEY AND
STRENGTHEN TONIGHT AND SUNDAY AS 500MB SHORTWAVE IS FORECAST TO
AMPLIFY AS IT TRACKS EAST.

THE SPREAD IN THE MODELS BETWEEN THE NAM/GFS/ECMWF HAS DECREASED
THROUGH SUNDAY NIGHT...WHICH DOES LEND TO SOME UPTICK IN CONFIDENCE.
HOWEVER...IT IS STILL A COMPLEX INTERACTION OF SEVERAL KEY FEATURES
FORECAST TO TAKE PLACE AND NUMERICAL WEATHER GUIDANCE HAS HUNG US
OUT TO DRY REPEATEDLY THIS WINTER...MAKING IT HARD TO GO RUNNING
BACK INTO ITS OPEN ARMS AND TRUSTING IT. STILL...GIVEN THE
DECREASING SPREAD IN THE MODELS THROUGH SUNDAY NIGHT IT IS A BIT
EASIER TO DEVELOP SOME MORE CONFIDENCE IN THE FORECAST EVOLUTION OF
THIS SYSTEM.

NITTY GRITTY DETAILS...
BROAD AND STRENGTHENING WARM AIR ADVECTION REGIME IS LIKELY TO
RESULT IN AN EXPANDING SHIELD OF PRECIPITATION FROM THE LOWER
MISSOURI VALLEY THIS MORNING EASTWARD INTO OUR AREA LATE THIS
AFTERNOON AND EARLY THIS EVENING. INITIALLY IT WOULD APPEAR AS
THOUGH TEMPERATURES TODAY WILL BE WARM ENOUGH FOR PRECIPITATION TO
BE ALL RAIN. WEAK FRONT IS FORECAST TO BASICALLY BISECT THE CWA AT
00Z THIS EVENING AND ONLY SLOWLY SAG SOUTH THROUGH THE NIGHT. TO THE
SOUTH OF THE WEAK FRONT LOOK FOR SOUTHERLY WINDS AND CONTINUED WARM
AIR ADVECTION TO HOLD TEMPERATURES NEAR OR PERHAPS JUST ABOVE
FREEZING SOUTH OF I-80 EARLY THIS EVENING AND PERHAPS INTO THE LATE
EVENING SOUTH OF THE ILLINOIS AND KANKAKEE RIVERS. AM CONCERNED
BECAUSE A VERY COMMON BIAS IN MODEL GUIDANCE IS TO UNDERESTIMATE THE
IMPACTS OF WARM AIR ADVECTION ON P-TYPE IN DEVELOPING CYCLONES LIKE
THIS...WHICH IF ALL THE MASS FIELDS VERIFY PERFECTLY HAS ME
CONCERNED THAT PRECIP COULD BE RAIN OR HAVE RAIN MIXED IN WELL INTO
THE EVENING HOURS INTO SOUTHERN AND POSSIBLY EVEN CENTRAL PORTIONS
OF THE CWA. GIVEN THIS CONCERN HAVE GREATLY REDUCED SNOW ACCUMS THIS
EVENING...ESPECIALLY SOUTH OF I-80 AND EVEN LOWERED RATIOS INTO
SUNDAY MORNING WHERE FORECAST MODEL 2M TEMPS NEAR 32F MAKE ME VERY
LEARY OF SEEING BIG ACCUMULATIONS OCCUR. THE AREAS SOUTH OF
KANKAKEE/ILLINOIS RIVERS SEEM TO STAND THE HIGHEST CHANCE OF A
FORECAST BUST AND IF THE ACCUMULATING SNOW STARTS LATE ENOUGH COULD
EASILY END UP BELOW 5 INCHES FOR THE 24 HOURS PERIOD.

CONFIDENCE IS LOW WHEN PRECIP WILL TURN TO ALL SNOW FAR SOUTH THOUGH
SREF GUIDANCE SUGGESTS BY 06Z...WORRIED THIS COULD BE DELAYED IF THE
TYPICAL MODEL BIAS OF UNDERESTIMATING WAA MAGNITUDE PLAYS OUT.
EVENTUALLY IT WILL TURN TO ALL SNOW AND SHOULD BEGIN TO ACCUMULATE
IF NOT LATE TONIGHT THEN CERTAINLY DURING THE DAY ON SUNDAY AS TEMPS
BEGIN TO PLUMMET. PRECIP LOOKS MORE LIKELY TO BE ALL SNOW NORTH OF
I-88/290...THOUGH THERMAL FIELDS AND FORECAST OMEGA VALUES DO NOT
SUPPORT HIGH SNOW:LIQUID RATIOS FOR THE MAJORITY OF THE EVENT. BY
SUNDAY AFTERNOON AS WE TRANSITION INTO THE DEFORMATION ZONE AND
COLUMN COOLS WILL LIKELY SEE A GRADUAL TRANSITION TO DRIER/HIGHER
RATIO SNOWS.

MODEL QPF REMAINS VERY IMPRESSIVE WITH MAJORITY OF MODELS LAYING OUT
A SWATH OF LIQUID EQUIVS OF 1" OR GREATER OVER PORTIONS OF OUR CWA.
SYSTEM WILL BEGIN TO TAP INTO THE HIGHER PWAT AIR MASS OVER THE GULF
OF MEXICO AND GFS/NAM AGREE THAT PWATS WILL CLIMB TO OVER 0.5" INTO
OUR CWA WHICH IS IN THE 90TH PERCENTILE OF PWATS FOR THIS TIME OF
YEAR. MODELS REALLY NEVER SHOW ANY INTENSE/STRONG ASCENT...BUT
RATHER A LONG DURATION OF MODEST ASCENT WHICH GIVEN THE ACCOMPANYING
UNSEASONABLY MOIST AIR MASS COULD CERTAINLY SUPPORT FORECAST QPF
VALUES. THE MILLION DOLLAR QUESTION IS HOW MUCH OF THE PRECIP WILL
FALL AS ALL SNOW AND HOW LONG WILL IT TAKE IT TO START ACCUMULATING.
THE FARTHER NORTH YOU GO INTO THE CWA THE LESSER THE CHANCE AND
SHORTER THE DURATION OF ANY MIXED SLEET OR RAIN AND THE SOONER SNOW
WILL ACCUMULATE. THIS AREA IS WHERE THE SLIGHTLY LESSER QPF VALUES
ARE...WHILE FARTHER SOUTH WITHIN THE SWATH OF FORECAST QPF >1 INCH
THERE ARE BIG QUESTIONS ABOUT DURATION OF ANY MIXED RAIN AND HOW
SOON AFTER THE TRANSITION TO SNOW THAT IT WILL START TO ACCUMULATE.
IF PRECIP STARTS AS RAIN AND TURNS TO SNOW WITH TEMPS OF 32F OR 33F
THEN IT COULD SNOW FOR A WHILE BEFORE ACCUMULATING...AND FOR THIS
REASON HAS SHOWN AT LEAST A THIRD OF AN INCH OF THE QPF FALLING AS
RAIN OR NON-ACCUMULATING SNOW.

GIVEN THE CURRENT FORECAST TRACK THE AXIS OF HEAVIEST SNOW LOOKS TO
LAY OUT SOMEWHERE IN THE I-80 OR I-88/290 CORRIDOR WHERE ACCUMS
COULD POTENTIALLY PUSH DOUBLE DIGITS BY THE TIME IT IS ALL SAID AND
DONE SUNDAY EVENING. EVEN OUTSIDE THIS SWATH SIGNIFICANT
ACCUMULATIONS OF 5-8 INCHES LOOK PRETTY LIKELY. STRENGTHENING
NORTHEAST WINDS AND COMBINED WITH GRADUALLY DECREASING SNOW DENSITY
SHOULD ALLOW FOR SOME BLOWING AND DRIFTING SNOW TO DEVELOP SUNDAY
AFTERNOON AND CONTINUED INTO SUNDAY EVENING...ESPECIALLY NORTHERN
CWA WHERE SNOW SHOULD BE LIGHTEST AND MOST BLOWABLE.

LAKE ENHANCEMENT/LAKE EFFECT...
AS DEPTH OF THE COLD AIR MASS BEGINS TO INCREASE SUNDAY AFTERNOON
AND EVENING LOOK FOR THE POTENTIAL FOR INITIALLY SOME LAKE
ENHANCEMENT PROBABLY TRANSITIONING TO PURE LAKE EFFECT SUNDAY NIGHT
AS SYSTEM SNOWS MOVE OUT. OVERALL THE LAKE EFFECT SET-UP APPEARS
MARGINAL AND DESPITE THE STRONG CONVERGENCE/LOW LEVEL ASCENT
INDICATED IN THE HIGH-RES MODELS SUSPECT THE LAKE CONTRIBUTIONS TO
THE SNOWFALL WILL NOT BE TERRIBLY SIGNIFICANT. INVERSION HEIGHTS
NEAR OR BELOW 5000FT SUGGEST CONVECTION WILL BE SHALLOW AND DESPITE
FAVORABLE TEMPS BELOW THE INVERSION FOR SNOW GROWTH...THE DEPTH OF
THE CONVECTION LOOKS TOO SHALLOW TO SUPPORT MUCH MORE THAN LIGHT
LAKE EFFECT SNOW SHOWERS. THE LOW LEVEL INSTABILITY IS ALSO PROGGED
TO BE WEAK WITH ONLY A COUPLE HUNDRED JOULES OF LAKE INDUCED CAPE
BELOW THE INVERSION. GIVEN THE CURRENT FORECAST THERMODYNAMICS
THINKING THAT THE LAKE CONTRIBUTIONS TO SNOWFALL TOTALS WILL BE
MINIMAL BUT PROBABLY ENOUGH TO KEEP LIGHT SNOW SHOWERS GOING SO HAVE
MAINTAINED THE HIGH POPS NEAR THE LAKE SUNDAY NIGHT.

LAKESHORE FLOOD THREAT...
STRONG NORTHEAST WINDS UP TO GALE FORCE WILL LIKELY RESULT IN
LARGE AND BATTERING WAVES DEVELOPING ALONG THE ILLINOIS AND
INDIANA SHORES SUNDAY AFTERNOON AND EVENING. LAKE LEVELS REMAIN
NEARLY A FOOT AND A HALF ABOVE NORMAL...THOUGH DOWN A BIT FROM
WHERE THEY WERE DURING THE HALLOWEEN STORM. ALONG THE LAKEFRONT
FRIDAY AFTERNOON I SAW A LOT OF FRAZZLE ICE HAD DEVELOPED WHICH
COULD HAVE THE EFFECT TO DAMPEN WAVES A BIT ALONG THE SHORE. NONE-
THE-LESS SOME MINOR LAKESHORE FLOODING IS POSSIBLE IF WAVES BUILD
UP TO 10 TO 14 FT AS FORECAST...THOUGH IMPACTS WILL LIKELY BE
PRETTY TRIVIAL SO NOT PLANNING ANY LAKESHORE FLOOD HEADLINES AT
THIS TIME. NOT OUT OF THE QUESTION THAT WE MAY NEED A LAKESHORE
FLOOD ADVISORY EVENTUALLY...PARTICULARLY IF WIND/WAVE FORECAST
GOES ANY HIGHER.

IZZI

&&

.LONG TERM...
200 AM CST

MONDAY THROUGH FRIDAY...

BY MONDAY MORNING...THE SYSTEM THAT IS EXPECTED TO BRING THE WEEKEND
SNOWFALL SHOULD SHIFT WELL TO THE EAST...WITH THE SFC LOW MOVING TO
THE MID ATLANTIC REGION WHILE HIGH PRESSURE BUILDS JUST WEST OF THE
MISSISSIPPI RIVER.  THE RESULTANT LONG...NORTHERLY FETCH OVER LAKE
MICHIGAN SHOULD BE CONDUCIVE TO A LAKE EFFECT BAND OF SNOW
DEVELOPING ALONG THE SPINE OF THE LAKE...AND THE SFC WIND FIELD
ADVERTISED BY MUCH OF THE GUIDANCE DOES INDICATE A SFC CONVERGENCE
BAND AS WELL.  SO...WOULD EXPECT A BAND OF LAKE EFFECT SNOW SHOWERS
POINTING INTO NWRN INDIANA MONDAY MORNING.  THE OVERALL PATTERN
SHOULD BE FAIRLY PROGRESSIVE...SO DO NOT ANTICIPATE THAT A BAND
WOULD SET UP OVER A SINGLE AREA FOR VERY LONG...WITH THE LAKE EFFECT
BAND GRADUALLY MOVING EAST THROUGH THE DAY...PERHAPS JUST CLIPPING
NERN PORTER COUNTY IN THE AFTERNOON.  FOLLOWING THE SYNOPTIC
SNOW...DO NOT ANTICIPATE THAT THIS LAKE EFFECT BAND WOULD
SIGNIFICANTLY ADD TO THE PREVIOUS SNOWFALL.  AS THE SFC HIGH
PRESSURE BUILDS EWD THROUGH THE DAY...TEMPERATURES ACROSS THE REGION
WILL LIKELY ONLY SEE A 5 TO 10 DEGREE DIURNAL RISE THROUGH THE DAY
WITH HIGHS ONLY IN THE TEENS.  BY TUESDAY...THE UPPER LEVEL PATTERN
IS EXPECTED TO BECOME MUCH MORE ZONAL...WITH A SERIES OF WEAK
SHORTWAVES RIPPLING THROUGH THE FAST UPPER LEVEL FLOW.  TIMING OF
INDIVIDUAL SHORTWAVES IN FAST ZONAL FLOW ALOFT BECOMES MORE
PROBLEMATIC WITH TIME...SO CONFIDENCE IN THE EXACT TIMING OF ANY
INDIVIDUAL SYSTEM IMPACTING THE REGION WOULD BE MODERATE AT BEST.
HOWEVER...THAT BEING SAID...THE NEXT CHANCE FOR PCPN ACROSS THE AREA
SHOULD BE MONDAY NIGHT INTO TUESDAY MORNING AS A WEAK
PACIFIC-SOURCED SHORTWAVE QUICKLY SCOOT ACROSS THE AREA...POSSIBLY
BRINGING A LITTLE LIGHT SNOW.  WITH HIGH PRESSURE EXTENDING FROM THE
UPPER OHIO VALLEY THROUGH EAST TEXAS...THERE WILL LITTLE MOISTURE
TRANSPORT FROM THE GLFMEX AND ANY ACCUMULATIONS ASSOCIATED WITH THIS
SYSTEM SHOULD BE LIGHT.  ANOTHER PACIFIC SHORTWAVE...QUICK ON THE
HEELS OF THE FIRST ONE MAY BRING SOME MORE LIGHT SNOW FOR TUESDAY
NIGHT INTO WEDNESDAY...BUT AGAIN...ANY ACCUMULATIONS SHOULD BE
LIGHT.  BY WEDNESDAY NIGHT...ARCTIC HIGH PRESSURE BUILDING OUT OF
CANADA SHOULD SPREAD ACROSS THE NRN PLAINS AND ACROSS THE GREAT
LAKES REGION BY THURSDAY MORNING.  THIS WILL BRING MUCH COLDER
AIR...WITH LOWS DROPPING BELOW 0F OVER THE NWRN PORTIONS OF THE CWA
THURSDAY MORNING...WITH THE REMAINDER OF THE AREA DROPPING INTO THE
SINGLE DIGITS ABOVE 0F. THE COLD...ARCTIC HIGH PRESSURE WILL
DOMINATE THE REGION FOR THE REMAINDER OF THE WEEK.  THE COLDEST
PERIOD SHOULD BE THURSDAY NIGHT INTO FRIDAY MORNING TEMPERATURES
BELOW 0F OVER MUCH OF THE AREA AWAY FROM THE IMMEDIATE
LAKEFRONT...AND EVEN THERE...TEMPERATURES SHOULD ONLY BE IN THE
LOWER SINGLE DIGITS ABOVE ZERO.  THERE SHOULD BE A LITTLE MODERATION
TO TEMPERATURES BY FRIDAY AS THE CENTER OF THE HIGH SLIDES TO THE
EAST AND LOW LEVEL FLOW BECOMES MORE SOUTHERLY...DRAWING SOME
SLIGHTLY WARMER AIR INTO THE REGION WITH HIGHS ON FRIDAY IN THE
UPPER TEENS TO LOWER 20S.

KREIN

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 09Z...

* NONE THROUGH MID AFTERNOON.

* CIGS LOWERING TO MVFR LATE AFTERNOON THEN IFR BY LATE EVENING OR
  EARLY OVERNIGHT IN SNOW.

* SNOW SPREADS IN EARLY/MID EVENING CONTINUING THROUGH THE NIGHT.
  INTENSITY MAY WANE AT TIMES DURING THE EARLY OVERNIGHT...BUT
  PICK UP LATE.

* IFR VSBY EXPECTED IN SNOW BUT MAY SEE SOME INTERMITTENT
  IMPROVEMENT DURING THE EARLY OVERNIGHT HOURS.

* WINDS TURN FROM SOUTHWEST TO NORTHEAST EARLY/MID EVENING. MAY BE
  A PERIOD OF VARIABLE WINDS AROUND/JUST AFTER SUNSET. SPEEDS
  INCREASE EARLY SUNDAY MORNING.

KREIN

//DISCUSSION...UPDATED 06Z...

QUIET WEATHER WILL PERSIST THROUGH MID AFTERNOON WITH LIGHT/VARIABLE
SOUTH TO SOUTHWEST WINDS BECOMING STEADIER SOUTHWEST LATER THIS
MORNING. VFR WILL CONTINUE BUT CLOUDS WILL THICKEN AND LOWER THIS
AFTERNOON AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM. EXPECT MVFR
TO DEVELOP QUICKLY LATE THIS AFTERNOON.

SNOW WILL SPREAD IN FROM THE SOUTHWEST THIS EVENING..OCCURRING
EARLIEST AT RFD. AREAS SOUTH OF THE TERMINALS MAY SEE PRECIP START
AS A MIX OF RAIN /SLEET/SNOW THEN TRANSITION TO ALL SNOW LATE
EVENING OR OVERNIGHT. HAVE DECENT CONFIDENCE IN TIMING OF THE ONSET
OF SNOW AT THE TERMINALS. LOW LEVEL FLOW WILL BE TURNING
NORTHEASTERLY DURING THE EVENING SO SNOW INTENSITY MAY EASE UP JUST
A BIT AS STEADIER NORTHEAST FLOW DEVELOPS BRINGING IN DRIER AIR. IT
APPEARS THAT SNOW WILL FALL HEAVILY ENOUGH TO BRING IFR VSBY DURING
THE EVENING BUT IT MAY END UP BEING SOMEWHAT
INTERMITTENT...ESPECIALLY FOR A TIME AROUND/AFTER 06Z. SNOW
INTENSITY IS EXPECTED TO INCREASE/PEAK AROUND/AFTER 09Z THEN PERSIST
THROUGH THE REST OF THE MORNING BEFORE WANING AGAIN EARLY SUNDAY
AFTERNOON. SUB 3/4SM OR EVEN 1/2SM VSBY IS MOST LIKELY DURING THIS
TIME. PEAK SNOW ACCUMULATION RATES OF BETWEEN 0.5 AND 0.75 IN/HR ARE
EXPECTED TO BE MOST PREVALENT WITH BRIEF PEAKS NEAR 1.0 IN/HR
POSSIBLE AT TIMES SATURDAY NIGHT AND SUNDAY. SURFACE WINDS WILL TURN
NORTHEASTERLY DURING THE EVENING THEN STEADILY INCREASE IN SPEED
SUNDAY MORNING. GUSTS OF 25-30 KT ARE EXPECTED BY LATE SUNDAY
MORNING WHICH WILL LIKELY RESULT IN BLOWING AND DRIFTING SNOW...AND
GUSTS NEAR 35 KT ARE A POSSIBILITY DURING THE AFTERNOON. WILL ALSO
NEED TO MONITOR LAKE EFFECT SNOW POTENTIAL LATE SUNDAY AFTERNOON
INTO MONDAY MORNING WHICH WOULD LIKELY RESULT IN A RETURN TO IFR
CONDITIONS WITH ADDITIONAL ACCUMULATIONS BUT IT IS NOT CLEAR HOW
LONG THE DURATION MAY BE...ESPECIALLY AT ORD/MDW/DPA.

MDB

//ORD AND MDW CONFIDENCE...UPDATED 09Z...

* HIGH CONFIDENCE ALL ELEMENTS THROUGH MID AFTERNOON.

* HIGH CONFIDENCE IN CIGS LOWERING LATE IN THE AFTERNOON. MEDIUM
  CONFIDENCE IN TIMING OF MVFR ARRIVAL.

* HIGH CONFIDENCE IN SNOW SPREADING IN EARLY/MID EVENING. MEDIUM-
  HIGH CONFIDENCE IN EXACT TIMING. MEDIUM-HIGH CONFIDENCE THAT
  HIGHEST INTENSITY SNOW WILL BEGIN AROUND/AFTER 09Z SUNDAY
  MORNING.

* MEDIUM-HIGH CONFIDENCE IN IFR VSBY OCCURRING DURING THE EVENING AND
  LOW-MEDIUM CONFIDENCE THAT SOME INTERMITTENT IMPROVEMENT WILL
  OCCUR DURING THE EARLY OVERNIGHT. HIGHER CONFIDENCE LOWEST VSBY
  AROUND/AFTER 09Z SUNDAY MORNING.

* HIGH CONFIDENCE IN SOUTHWEST WINDS TURNING NORTHEAST DURING THE
  EVENING. MEDIUM CONFIDENCE IN TIMING. HIGH CONFIDENCE IN SPEEDS
  INCREASING EARLY SUNDAY MORNING.

KREIN

//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...

SUNDAY...SNOW THROUGH THE DAY...TAPERING OFF OVERNIGHT. MVFR
CIGS/VIS WITH PERIODS OF IFR CONDITIONS EXPECTED...ESPECIALLY
DURING THE MORNING.

MONDAY...VFR/WX NIL EARLY. SLIGHT CHANCE SNOW OVERNIGHT. MVFR
CIGS/VIS LIKELY.

TUESDAY AND WEDNESDAY...CHANCE OF SNOW. PERIODS OF MVFR CIGS/VIS
LIKELY.

THURSDAY...VFR/WX NIL.

MDB

&&

.MARINE...
243 AM CST

DISCUSSION...INCREASING NORTHEAST WINDS TONIGHT AND SUNDAY...LIKELY
REACHING GALE FORCE ACROSS SOUTHERN LAKE MICHIGAN WILL BE THE FOCUS
OF THE FORECAST. HIGH PRESSURE IS SPREAD FROM THE LOWER LAKES ACROSS
THE OHIO VALLEY AND TO THE GULF COAST THIS MORNING. WEST TO
SOUTHWEST WINDS HAVE SET UP ACROSS THE LAKE BEHIND THE HIGH. ONE AREA
OF LOW PRESSURE MOVING ACROSS NORTHERN ONTARIO WILL BRING A TROUGH
ACROSS THE LAKE INTO THE AFTERNOON TURNING WINDS NORTHWESTERLY THEN
NORTHEASTERLY LATE AS A NEW LOW DEVELOPS ACROSS THE FRONT RANGE OF
THE ROCKIES...WHICH THEN DEEPENS ACROSS KANSAS AND MISSOURI. SPEEDS
WILL STEADILY INCREASE TONIGHT AND PEAK SUNDAY AS THE LOW TRACKS
INTO CENTRAL INDIANA. WINDS WILL THEN TURN NORTHERLY SUNDAY EVENING
AS THE LOW TRACKS TO THE EAST AND HIGH PRESSURE APPROACHES FROM THE
WEST. STEADY 25-30 KT WINDS ARE LIKELY BY SUNDAY AFTERNOON WITH
GUSTS TO GALE FORCE AROUND 35 KT. THE SYSTEM HAS SHOWED A STRONGER
TREND NOW THAT THE FEATURES DRIVING IT ARE COMING TOGETHER SO 40 KT
IS NOT OUT OF THE QUESTION. WILL CONTINUE WITH THE GALE WATCH FOR
SOUTHERN LAKE MICHIGAN AND THE NEARSHORE WATERS. SOME ICE HAS FORMED
ALONG THE SHORELINE FRIDAY BUT IT LIKELY THIN AND MAY BREAK UP TODAY
THANKS TO MILDER TEMPS AND SOME SUN EARLY. IF NOTHING ELSE
INCREASING WINDS WILL LIKELY BREAK IT UP SO THERE MAY BE LITTLE
TEMPERING AFFECT ON THE WAVES AS A RESULT.

WINDS SLACKEN INTO MONDAY MORNING WITH HIGH PRESSURE PASSING SOUTH
OF THE LAKE LATER IN THE DAY. ANOTHER LOW. SEVERAL LOWS CROSS THE
REGION TUESDAY AND WEDNESDAY BRINGING A PERIOD OF MODEST SOUTHWEST
WINDS BUT A SHIFT TO NORTHWEST WILL OCCUR WEDNESDAY WITH STRONG HIGH
PRESSURE SPREADING IN WEDNESDAY NIGHT.

KREIN

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER STORM WARNING...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
     ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
     ILZ023-ILZ032-ILZ033-ILZ039...9 PM SATURDAY TO 9 PM SUNDAY.

IN...WINTER STORM WARNING...INZ001-INZ002-INZ010-INZ011-INZ019...9 PM
     SATURDAY TO 9 PM SUNDAY.

LM...GALE WATCH...LMZ080-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-LMZ742-
     LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ872-LMZ874-LMZ876-
     LMZ878...NOON SUNDAY TO MIDNIGHT MONDAY.

&&

$$

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