Area Forecast Discussion
Issued by NWS Chicago, IL

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000
FXUS63 KLOT 240843
AFDLOT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
243 AM CST WED DEC 24 2014

.UPDATE...
855 PM CST

OBSERVED DATA IS STARTING TO GIVE SOME BETTER CLUES AS TO HOW THE
STRONG LOW PRESSURE SYSTEM TO PASS TO THE EAST OF THE AREA WILL
PLAY OUT. LATEST SURFACE OBS SHOW AN INVERTED TROUGH TAKING SHAPE
FROM THE MISSISSIPPI COAST TO FAR SOUTH CENTRAL INDIANA WHERE IT
THEN ARCS NORTHEAST INTO FAR NORTHWEST OHIO. BASED ON WIND FIELDS
ON THE NORTHERN PORTIONS OF THE TROUGH IT APPEARS THAT THE
ULTIMATE TRACK OF THE LOW WOULD BE A LITTLE FURTHER EAST THAN
EARLIER GUIDANCE AND FORECASTS SUGGESTED. THIS WOULD TAKE THE LOW
EAST OF INDIANAPOLIS THOUGH PROBABLY NOT AS FAR EAST AS
RICHMOND...THEN UP INTO FAR NORTHWEST OHIO TOWARDS DEFIANCE.
TREND OF PRESSURE FALLS HAS BEEN TAKING THEM FROM SOUTHEAST
INDIANA UP ACROSS THE CINCINNATI AREA TOWARDS COLUMBUS SUPPORTING
THE FURTHER EAST TRACK AND PERHAPS ONE FURTHER EAST OF THE TRACK
DESCRIBED ABOVE. 18Z GUIDANCE HAD HINTED AT A FURTHER EAST TRACK
BUT MANAGED TO KEEP MUCH OF THE ASSOCIATED FRONTOGENETICAL FORCING
WELL TO THE WEST AND ACROSS NORTHEAST ILLINOIS/NORTHWEST INDIANA.
THE 00Z NAM HAS COME IN AND IS FURTHER EAST WITH THE SURFACE LOW
AND IN ALIGNMENT WITH THE ANALYSIS ABOVE. HAVE CONSIDERED SHIFTING
GEARS A BIT TAKING THE FOCUS FOR HEAVIEST PRECIP A LITTLE FURTHER
EAST BUT WITH THE INCONSISTENCY OF THE NAM OF LATE...THE PENDING
ARRIVAL OF A MYRIAD OF NEW 00Z GUIDANCE AND COORDINATION WITH
NEIGHBORING WFOS AND WPC...WILL HOLD OFF ON ANY CHANGES FOR NOW.
THERMAL PROFILES CONTINUE TO BE A CHALLENGE AND MAY STILL REQUIRE
VERY STRONG FORCING TO PRODUCE ALL SNOW. IT APPEARS THAT THE BEST
FORCING MAY TRY TO SHIFT A LITTLE TO THE EAST OF THE GOING
FORECAST SUGGESTING THAT THE IL/IN STATE LINE AREA AND MUCH OF
NORTHWEST INDIANA MAY BE THE FOCUS FOR INTENSE SNOWFALL RATES AND
THE HIGHEST ACCUMULATION POTENTIAL...WITH A SECONDARY AREA OF
FGEN FORCING SPREAD ACROSS NW IL WHICH COULD PRODUCE A PERIOD OF
ALL SNOW OVER A BROADER AREA. LATE MORNING THROUGH MID AFTERNOON
STILL LOOKS TO BE THE MAIN TIME FRAME...THOUGH AN EARLIER CHANGE
OVER IN NW INDIANA IS POSSIBLE AND ANY HEADLINES MAY NEED TO BE
STARTED EARLIER.

WILL LEAVE HEADLINES AS-IS FOR NOW AND RE-ISSUE SPS FOR NORTHWEST
AREAS NOT IN A HEADLINE HIGHLIGHTING POTENTIAL IMPACTS TO THE
EAST. WILL BOLSTER WORDING IN AN SPS FOR JASPER AND BENTON
COUNTIES AS IT IS POSSIBLE A HEADLINE MAY NEED TO BE ISSUED FOR
THEM TONIGHT.

MDB

&&

.SHORT TERM...
309 PM CST

SYNOPSIS...

A POWERFUL LOW PRESSURE SYSTEM WILL IMPACT NORTHERN AND CENTRAL
ILLINOIS AND NORTHWEST INDIANA ON CHRISTMAS EVE. DESPITE QUITE
MARGINAL TEMPERATURES FOR SNOW...THE STORM IS EXPECTED TO PRODUCE
INTENSE ENOUGH PRECIPITATION TO CAUSE INITIAL RAIN OR A MIX TO
CHANGE OVER TO HEAVY AT TIMES WET SNOW. A FAIRLY NARROW BAND OF
INTENSE SNOW IS EXPECTED. IN THIS AREA...SIGNIFICANT ACCUMULATIONS
POTENTIALLY RESULTING IN SUBSTANTIAL TRAVEL IMPACTS ON A VERY BUSY
TRAVEL DAY MAY OCCUR. THIS WILL INCLUDE AT LEAST PART OF THE HEART
OF THE CHICAGO METRO. WHILE CONFIDENCE REMAINS ON THE LOWER SIDE
WITH THIS COMPLEX SYSTEM...FELT IT WAS PRUDENT TO ISSUE A WINTER
STORM WATCH FOR MUCH OF THE CHICAGO METRO WHERE THE MOST SIGNIFICANT
IMPACTS COULD OCCUR. HAVE ALSO ISSUED A WINTER WEATHER ADVISORY
SURROUNDING THE WATCH AREA...WHERE HAZARDOUS TRAVEL IS EXPECTED BUT
SLIGHTLY LOWER SNOWFALL AMOUNTS.

WINTER STORM...TONIGHT THROUGH WEDNESDAY NIGHT...

SURFACE ANALYSIS SHOWS DEVELOPING LOW PRESSURE AREA ALREADY DOWN TO
JUST UNDER 1000 MB NEAR NEW ORLEANS. THERE IS A SUBSTANTIAL AMOUNT
OF CONVECTION NEAR THE GULF COAST AND THE TORNADO WATCH IN EFFECT
THERE SHOWS THE AMOUNT OF ENERGY AND MOISTURE ASSOCIATED WITH THIS
DEVELOPING SYSTEM. MOIST PLUME SURGING NORTHWARD IS QUITE EVIDENT ON
WATER VAPOR IMAGERY AND WILL CONTRIBUTE TO ANOMALOUSLY HIGH PWAT
VALUES ALSO FAVORABLE FOR HEAVY PRECIPITATION. MUST NOTE THAT
THE AMOUNT OF CONVECTION NEAR THE GULF MAY BE PLAYING SOME HAVOC
WITH UPPER LEVEL LOW EVOLUTION AND SFC LOW TRACK FORECASTS AMONGST
THE VARIOUS MODELS..PARTICULARLY THE NON- CONVECTION ALLOWING
GLOBAL MODELS.

AS THE SURFACE LOW TRACKS NORTHWARD TONIGHT...SHARPLY DIGGING
UPPER/MID LEVEL TROUGH WILL INTENSITY THANKS TO NEARLY 140 KT
UPPER JET SAMPLED BY 12Z RAOB AT GJT ROUNDING THE BASE OF THE
TROUGH. INTENSIFICATION OF MID LEVEL LOW WILL ALSO TRANSLATE TO
DEEPENING OF SFC LOW AS IT LIFTS NORTHWARD TOWARD THE OHIO VALLEY
BY DAYBREAK AND THEN LOWER MICHIGAN BY LATER IN THE DAY DOWN TO
SUB 990 MB. THIS TRACK IS TYPICALLY FAVORABLE FOR HEAVY SNOW
SOMEWHERE IN OUR AREA. THE HUGE QUESTION MARK CONTINUES TO BE THE
QUITE MARGINAL THERMAL PROFILES AND ALSO THE VERY MILD
TEMPERATURES THIS AFTERNOON THAT ARE CAUSING WARM ROAD SURFACES.

ALSO STILL HAVE A QUESTION ON SPEED/TIMING OF SFC LOW LIFTING
NORTHWARD...WITH GFS ON FASTEST SIDE AND LIKELY TOO FAST...WHILE 12Z
NAM WAS LIKELY A SLOW/DEEP OUTLIER. FURTHERMORE...TYPICALLY RELIABLE
ECMWF SHIFTED EASTWARD TODAY...WHICH LOWERS CONFIDENCE SOME...BUT IN
COLLAB WITH WPC...FELT EC WAS A FAR EAST OUTLIER.

WITH ALL THIS BEING SAID...THE RAPIDLY DEEPENING CIRCULATION IS
EXPECTED TO FORM A VERY IMPRESSIVE TROWAL WRAPPING AROUND
IT...WITH VERY INTENSE 850-700 MB FRONTOGENESIS AND OMEGA WITHIN
THIS TROWAL/DEFORMATION AXIS. INITIAL PRECIP SPREADING NORTHWARD
TOWARD DAYBREAK IS LIKELY TO BE MAINLY RAIN OR A MIX...AND HAVE
PRETTY GOOD CONFIDENCE IN THIS. THE KEY TIMEFRAME WILL COME AS THE
MORNING PROGRESSES ONWARD...WITH RESPECT TO DYNAMIC COOLING
RESPONSE FROM THE INTENSE UPWARD MOTION IN THE DEFORMATION
AXIS/TROWAL. ALSO AIDING IN THIS WILL BE THE EXISTING VERY STEEP
LAPSE RATES ABOVE 600 MB PLUS PRESENCE OF NEGATIVE EPV ABOVE THE
FGEN...WHICH ALSO MAKE LIGHTNING STRIKES A NON-ZERO POSSIBILITY.
FEEL THAT THE HIGHER RES GUIDANCE HAS A BETTER HANDLE ON THE
DYNAMIC COOLING POTENTIAL AND THE HEAVY PRECIP RATES WILL FORCE A
FLIP OVER TO A VERY HEAVY WET SNOW WITH TIME AND TEMPERATURES
GETTING FORCED DOWN CLOSER TO FREEZING.

UNFORTUNATELY FOR HOLIDAY TRAVELERS...MUCH OF THE 12Z DATA WITH THE
EXCEPTION OF THE ECMWF PLACED THE CHICAGO METRO IN THE CROSS HAIRS
OF THE BEST BANDING SIGNAL. CURRENT EXPECTATION IS FOR RAIN/MIX TO
CHANGE TO SNOW FROM SOUTHWEST TO NORTHEAST...GENERALLY MID/LATE
MORNING INTO EARLY AFTERNOON. ASSUMING CHANGEOVER OCCURS AS WE
EXPECT...AREAS WITHIN THE BAND COULD SEE 1-2"+ PER HOUR SNOWFALL
RATES DURING THE EARLY TO MID AFTERNOON...POTENTIALLY MAKING TRAVEL
NEARLY IMPOSSIBLE. THESE RATES WILL ALSO OVERCOME THE WARM ROAD
TEMPERATURES TO ENABLE ACCUMS ON SURFACES. WHILE HEAVY SNOW RATES
WILL LIKELY RESULT IN PERIODS OF VISIBILITY 1/4 MILE OR LESS...GUSTY
NORTH-NORTHWEST WINDS COULD CAUSE VISIBILITY ISSUES EVEN IN LIGHTER
SNOW RATES DESPITE WET NATURE OF THE SNOW. THE LOCATIONS THAT SEE
THE HEAVIEST SNOW COULD VERY WELL BE NARROWER THAN WHAT IS
DEPICTED IN THE GRIDS. HOWEVER...AS NOTED IN SYNOPSIS...FELT IT
WAS PRUDENT TO ISSUE AN IMPACT BASED WATCH FOR THE CHICAGO METRO
GIVEN THE CIRCUMSTANCES. WHILE MOST LOCATIONS LIKELY WILL NOT SEE
6" OF SNOW...SOMEWHERE WITHIN THE WATCH AREA COULD END UP WITH
6"+...WITH GENERALLY 2 TO 5 INCHES IN ADVISORY AREAS. THE SYSTEM
WILL LIFT OFF TO THE NORTHEAST QUICKLY DURING THE EVENING...SO
MUCH OF THE ACCUMULATING SNOW SHOULD BE OVER BY THEN.

OVERALL CONFIDENCE...MEDIUM.

THE MODERATE TO HEAVY SNOW ACCUMULATIONS ARE CONSIDERED A MORE
LIKELY SCENARIO. HOWEVER...THE BUST POTENTIAL WITH THIS SYSTEM
REMAINS HIGH GIVEN LINGERING UNCERTAINTY EVEN AT THIS LATE HOUR WITH
MARGINAL BOUNDARY LAYER CONDITIONS AND TRACK OF THE SURFACE
LOW/HEAVIEST PRECIP. CONTINUE TO STAY TUNED FOR THE LATEST
UPDATES.

RC

THURSDAY THROUGH FRIDAY NIGHT...

HIGH PRESSURE OVER THE GULF COAST WILL STRENGTHEN AS IT BUILDS
NORTHEAST TO THE MID ATLANTIC AND CAROLINAS...AS LOW PRESSURE OVER
THE SOUTH CENTRAL PLAINS LIFTS NORTHEAST TO THE WESTERN LAKES BY
FRIDAY AFTERNOON...AND THEN INTO QUEBEC SATURDAY MORNING. THE
GRADIENT WILL LIKELY REMAIN STRONG ENOUGH FOR SOME GUSTY SOUTHERLY
WINDS BOTH THURSDAY AND FRIDAY. WITH THIS SOUTHERLY FLOW...HIGH
TEMPS LIKELY TO REACH THE MID/UPPER 30S FRIDAY AND INTO THE 40S ON
FRIDAY. HOWEVER...HIGHS LIKELY TO BE IMPACTED BY LOCATION AND AMOUNT
OF SNOWFALL FROM WEDNESDAY AND DIDN/T TRY TO PIN DOWN COOLER AREAS
IN THE GRIDS JUST YET.

LOW LEVEL MOISTURE CONTINUES TO SPREAD ACROSS THE AREA FRIDAY INTO
FRIDAY NIGHT AS THE DEPTH OF THE SATURATED LAYER STEADILY INCREASES
AND REMAINS WELL ABOVE FREEZING. THUS SOME POTENTIAL FOR SPRINKLES
OR SHOWERS OR PERHAPS SOME DRIZZLE EXISTS. OPTED NOT TO INCLUDE ANY
MENTION YET BUT WILL NEED TO BE WATCHED. BY EVENING...COLDER AIR
WILL BE SLOWLY SPREADING INTO THE WESTERN CWA AHEAD OF A COLD FRONT
AND INCLUDED A MIX OF RAIN/SNOW AFTER MIDNIGHT. CMS

&&

.LONG TERM...
328 PM CST

SATURDAY THROUGH TUESDAY...

UPPER LEVEL SHORTWAVE TROUGH AND ASSOCIATED SURFACE COLD FRONT WILL
EXIT THE LOCAL AREA EARLY SATURDAY.  LINGERING PATCHY LIGHT RAIN AND
SNOW WILL TRANSITION TO A CHANCE OF LIGHT SNOW CONTINUING SATURDAY
EVENING AS COLDER AIR ADVECTS SOUTH AND EAST VIA A BRISK NORTHWEST
FLOW.  LARGE SPRAWLING HIGH PRESSURE OVER THE PLAINS THEN BUILDS
EAST INTO THE AREA SUNDAY WITH TEMPERATURES CLOSE TO SEASONAL
AVERAGES. AT LEAST PARTIAL SUNSHINE EXPECTED WILL GIVE THE APPEARANCE
OF A NICER DAY DURING A MONTH WHEN SUNSHINE HAS BEEN A RARE
COMMODITY.

MEANWHILE SHORTWAVE AMPLIFYING IN THE SOUTHERN STREAM HELPS ORGANIZE
SURFACE LOW PRESSURE ALONG THE LOUISIANA GULF COAST SUNDAY.  KEPT A
LOW POP CHANCE OF LIGHT SNOW MENTIONED IN THE FAR SOUTHEAST COUNTIES
ON MONDAY AS THIS LOW LIFTS NORTHEAST TO THE CENTRAL APPLICATIONS.
A COLD FRONT ASSOCIATED WITH A NORTHERN STREAM LOW MOVING ACROSS THE
PLAINS TO EASTERN LAKE SUPERIOR BY TUESDAY USHERS IN A REINFORCING
SHOT OF SEASONALLY CHILLY AIR ON FORECAST DAY 7... MOISTURE LOOKS
VERY LIMITED BUT MAY SEE A FLURRY OR TWO AS DECENT COLD ADVECTION
SQUEEZES OUT WHATEVER MOISTURE IS AVAILABLE.

ED F

&&

.AVIATION...

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

* RAIN OVERSPREADING THE TERMINALS INTO MID MORNING. CHANGE TO
  RAIN/SNOW WITH INTERMITTENT PERIODS OF ALL SNOW POSSIBLE MIDDAY
  INTO THE AFTERNOON...TAPERING OFF INTO THE EVENING.

* CIGS LOWER TO MVFR BY MID MORNING...THOUGH SPORADIC MVFR IS
  POSSIBLE UNTIL THEN...LOWERING TO IFR/LIFR TOWARD MIDDAY.

* MAINLY MVFR VSBY EXPECTED FROM MID MORNING ONWARD WITH
  INTERMITTENT IFR VSBY POSSIBLE...ESPECIALLY IF ALL SNOW CAN
  OCCUR AT TIMES.

* N/NNE WINDS TURN NORTHWEST TOWARD MIDDAY AND BECOME GUSTY.

MDB

//DISCUSSION...UPDATED 09Z...

NOT MUCH CHANGING IN THINKING THUS FAR OVERNIGHT. RAIN SHOWERS
ARE QUICKLY SPREADING NORTHWARD ACROSS NORTHEAST IL/NORTHWEST IN
WHICH IS ALSO BRINGING SPORADIC MVFR CIGS. BAND OF IFR TO THE WEST
HAS PUSHED INTO RFD AND LOOKS TO REMAIN THERE THROUGH DAYBREAK..IF
NOT LONGER. HAVE LESS CONFIDENCE IN WIND SPEEDS THROUGH THE
MORNING WITH LATEST TRENDS SUPPORTING LOWER SPEEDS AND PERHAPS
EVEN MINIMAL GUSTINESS THIS AFTERNOON. WILL TREND DOWN A FEW KNOTS
FOR NOW.

FROM 06Z...

UPCOMING STORM SYSTEM CONTINUES TO BE TRICKY BUT LATEST OBSERVED
TRENDS AND FORECAST GUIDANCE ARE HELPING TO ESTABLISH AT LEAST
MARGINALLY INCREASED CONFIDENCE IN HOW THINGS EVOLVE. LOW PRESSURE
IS DEVELOPING FROM THE MISSISSIPPI COAST ACROSS CENTRAL TENNESSEE
INTO FAR NORTHWEST OHIO EARLY TONIGHT. LOW PRESSURE IS EXPECTED TO
CONSOLIDATE AND TRACK ACROSS EASTERN INDIANA OR FAR WESTERN OHIO
THROUGH THE DAY WHILE UPPER LEVEL LOW PRESSURE LIFTS NORTHEAST
ACROSS INDIANA. THIS WILL SPREAD RAIN NORTHWARD ACROSS THE
TERMINALS THROUGH THE MORNING. A NARROW CORRIDOR OF VERY STRONG
FORCING IS EXPECTED TO DEVELOP ALONG OR JUST EAST OF THE IL/IN
BORDER INTO MIDDAY AND SHOULD LEAD TO A BAND OF ALL SNOW WHICH MAY
BE VERY INTENSE. PLACEMENT OF THIS BAND IS LOOKING TO BE TO THE
EAST OF EARLIER THINKING WITH ORD AND MDW FORECAST TO BE ON THE
FRINGE OR JUST WEST OF IT...WITH GYY LIKELY TO BE MOST AFFECTED
WITH MODERATE/HEAVY SNOW. HAVE THUS ADJUSTED THE TAFS AT
ORD/MDW/DPA TO REFLECT THIS THINKING AND BRING IMPROVED
CIGS/VSBY...THOUGH IFR/LIFR CIGS ARE STILL EXPECTED. ORD/DPA AND
ESPECIALLY MDW MAY STILL SEE INTERMITTENT PERIODS OF ALL SNOW AND
IFR VSBY BUT THIS COULD BE PESSIMISTIC. WILL CARRY PREVAILING
-RASN FOR THE AFTERNOON WITH TEMPO -SN FOR NOW. IF THE SNOW BAND
DOES DEVELOP THEN MAY NOT BE LOW ENOUGH AT GYY AS 1/4SM +SN IS A
POSSIBILITY. RFD IS MORE OF A CHALLENGE AND MAY END UP SEEING MORE
OF A DRIZZLE SCENARIO FOR A TIME VS. STEADIER LIGHT RAIN AND/OR
SNOW SO ADJUSTMENTS WILL PROBABLY BE NEEDED.

WINDS WILL TURN N/NNE OVERNIGHT AND BEGIN TO INCREASE IN SPEED
LATER IN THE MORNING AS THEY TURN NORTHWESTERLY. EXPECT GUSTS IN
THE 20-25 KT RANGE TO DEVELOP BUT THESE MAY HOLD OFF UNTIL WINDS
TURN NW. IFR CIGS AND MVFR VSBY LOOK TO PREVAIL THROUGH THE
EVENING BUT THERE MAY BE SOME IMPROVEMENT OF CIGS INTO THURSDAY
MORNING.

MDB

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

* HIGH CONFIDENCE IN RAIN OVERSPREADING THE TERMINALS INTO MID
  MORNING. MEDIUM CONFIDENCE IN CHANGE TO RAIN/SNOW AND ASSOCIATED
  TIMING. LOW CONFIDENCE IN PERIODS OF ALL SNOW OCCURRING AND
  TIMING.

* HIGH CONFIDENCE IN CIG TRENDS.

* MEDIUM CONFIDENCE IN MAINLY MVFR VSBY. MEDIUM-HIGH CONFIDENCE
  THAT INTERMITTENT IFR VSBY WOULD OCCUR IF ALL SNOW CAN FALL AT
  TIMES.

* HIGH CONFIDENCE IN WIND DIRECTION TRENDS BUT MEDIUM CONFIDENCE
  IN SPEEDS AND TIMING OF ARRIVAL OF GUSTS.

MDB

//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...

THURSDAY...MVFR/IFR IMPROVING TO VFR.
FRIDAY...MVFR/IFR POSSIBLE.
SATURDAY THROUGH MONDAY...MVFR POSSIBLE.

BMD

&&

.MARINE...
211 AM CST

A TROUGH OF LOW PRESSURE STRETCHING FROM THE MISSISSIPPI COAST
NORTHWARD INTO NORTHWEST OHIO WILL CONSOLIDATE INTO A QUICKLY
DEEPENING CLOSED LOW WHICH WILL TRACK FROM TENNESSEE TO GEORGIAN BAY
INTO TONIGHT. WEAK HIGH PRESSURE CURRENTLY OVER THE LAKE IS
PROVIDING LIGHT AND VARIABLE WINDS BUT THESE WILL QUICKLY TURN NORTH
TO NORTHEAST THROUGH THE MORNING WITH SPEEDS STEADILY INCREASING.
SPEEDS WILL INTENSIFY MORE RAPIDLY THIS AFTERNOON AS THE LOW TRACKS
ACROSS FAR NORTHWEST OHIO WITH THE DIRECTION TRENDING NORTH AND
NORTHWEST BEFORE TURNING WEST TONIGHT. PEAK SPEEDS LOOK TO OCCUR
THIS EVENING AND TONIGHT. THE SYSTEM IS TRACKING FURTHER TO THE EAST
WHICH WILL LIKELY LEAD TO SLIGHTLY WEAKER WINDS ACROSS THE LAKE BUT
SHOULD STILL SEE MARGINAL GALES SO WILL CONTINUE WITH THE GALE
WARNING FOR THE OPEN WATERS...BUT DELAY THE START UNTIL 21Z ACROSS
THE SOUTHERN PART OF THE LAKE. GALES LOOK MUCH LESS LIKELY ACROSS
THE IL/IN NEARSHORE WATERS SO WILL TRANSITION TO A SMALL CRAFT
ADVISORY.

HIGH PRESSURE WILL BUILD ACROSS THE GULF COAST AND SOUTHEAST
THURSDAY WITH A RIDGE AXIS MOVING ACROSS THE LAKE. THIS WILL TURN
WINDS SOUTHWESTERLY THURSDAY WITH SPEEDS EASING UP INTO THE EVENING.
A WEAK TROUGH AXIS WILL SET UP FROM THE TEXAS PANHANDLE TO LAKE
SUPERIOR INTO FRIDAY WITH THE HIGH STILL TO THE SOUTHEAST ALLOWING
FOR A STEADY SOUTHWEST WIND TO PERSIST ACROSS THE LAKE INTO
SATURDAY. A MORE CONSOLIDATED AREA OF LOW PRESSURE IS THEN EXPECTED
TO CROSS THE WESTERN LAKES OVER THE WEEKEND BRINGING A COLD FRONT
WITH IT AND A SHIFT TO WEST AND NORTHWEST WINDS. HIGH PRESSURE THEN
BUILDS IN EARLY NEXT WEEK.

MDB

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ014-ILZ022-ILZ023-ILZ033-
     ILZ039...NOON WEDNESDAY TO 9 PM WEDNESDAY.

IN...WINTER WEATHER ADVISORY...INZ001-INZ002-INZ010-INZ011-
     INZ019...NOON WEDNESDAY TO 9 PM WEDNESDAY.

LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-
     LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...3 PM WEDNESDAY TO 3 AM
     THURSDAY.

     GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-
     LMZ868...3 PM WEDNESDAY TO 6 AM THURSDAY.

     SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743...NOON
     WEDNESDAY TO 9 AM THURSDAY.

     SMALL CRAFT ADVISORY...LMZ744-LMZ745...NOON WEDNESDAY TO 3 PM
     THURSDAY.

&&

$$

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