se WI/ne IL/nw IN/se MI lake effect snow event

[Chicago Storm]

Watch it bust epically lol...

ARW style bust.

Looks good though... 3"

[weatherguru]

Not a snow weenie here but I agree with his maps. Lately with a more favorable NE IL lake snow and long duration I think it's right on target. Just may not be the exact location but quite similar in the end.

[weatherguru]

Nice hit so far between 24hr-42hr NE IL.

[ILSNOW]

What will KLOT do with the afternnon package? My guess Les Advisory for Lake (IL) and Les Warning for Cook and NW Indiana. Thoughts? My guess for Lake (IL) 2-4 with 4-8 Cook and east?

[weatherguru]

this was at 2pm

WINDS WILL CONTINUE TO VEER TO THE NE ABOUT 020-040 DEG...WITH

LAKE EFFECT SNOW DEVELOPING. THIS PRESENTS ANOTHER CHALLENGE FOR

AVIATION TRAFFIC AS THIS MAY ALLOW LAKE SN TO PUSH FURTHER INLAND

AND APPROACH ORD/MDW. BEST TIMING FOR THIS APPEARS TO BE AFT

00Z...WHICH HAS BEEN SIMILAR TO EARLIER THINKING OF TIMING. HAVE

CONTINUED TO HOLD VSBYS DOWN ARND 1SM FOR ORD/MDW/DPA/GYY...AND

COULD EASILY SEE GYY DROPPING FOR A PERIOD TO 1/4SM WITH A NARROW

BAND OF LAKE EFFECT SNOW OVERNIGHT. CIGS FOR RFD WILL START TO

IMPROVE ARND DAYBREAK SAT...GRADUALLY PUSHING TO MVFR CIGS BY

MIDDAY SAT. ELSEWHERE EXPECT CIGS TO LINGER ARND 1000-1500FT AGL

THRU MIDDAY SAT.

[weatherguru]

Oh Chicago look at that beautiful LES band that just sits in NE IL between 24hr-54hr SO FAR:

http://www.nco.ncep....8/fp0_054.shtml

Feeling confident a more organized and and narrow band will set up in Lake, Cook, Duage and Will Counties.

[ILSNOW]

KlLOT in their 1:45 multi media briefing is calling for 1-3 Lake (IL) AND Cook with 4-7 in southeastern Cook and in NW Indiana.

[Chicago Storm]

MKE

ALREADY SEEING SOME LAKE BANDS KICKING UP EAST OF MILWAUKEE AND RACINE.

MORE UPSTREAM EAST OF KEWAUNEE AND MANITOWOC.

THE LAKE EFFECT POTENTIAL WILL CONTINUE INTO SATURDAY. DELTA T VALUES

REACH 16C AT THE HIGHEST ON SATURDAY WITH FAVORABLE TRAJECTORIES.

HOWEVER NAM 1000-850 MILLIBAR FOCUSES BEST CONVERGENCE OFFSHORE

WHILE GFS A BIT MORE FAVORABLE FOR BRINGING CONVERGENCE INTO THE

LAKESHORE COUNTIES. FLOWCHART SUGGESTS POTENTIAL FOR LIGHT ACCUMS.

UPPER FLOW REMAINS STRONGLY CYCLONIC SO WILL HAVE SOME FLURRIES CWA

WIDE AS SPOKES OF VORTICITY ROTATE THROUGH BUT THE MAIN FOCUS WILL

BE CLOSER TO THE LAKESHORE...ESPECIALLY FROM MILWAUKEE SOUTH.

SHORT TERM

SATURDAY NIGHT THROUGH MONDAY. FORECAST CONFIDENCE

MEDIUM.

MAIN PROBLEM IS TIMING AND INLAND EXTENT OF LAKE-EFFECT SNOW. LAST

SHORT WAVE/VORT MAX ON WESTERN FLANK OF 500MB TROUGH...AS IT CLOSES

OFF OVER EASTERN U.S...DROPS THOUGH STATE SATURDAY NIGHT. MID LAYERS

ARE DRY BUT LOWER LEVEL RELATIVE HUMIDITY TAPS LOWER EDGE OF

DENDRITE GROWTH ZONE AS LIFT WITH MID-UPPER LEVEL Q-VECTOR

CONVERGENCE MAX...MAINLY ATTRIBUTED TO CVA AHEAD OF VORT

MAX...CROSSES REGION. WILL KEEP SCATTERED FLURRIES IN FORECAST

INLAND SATURDAY NIGHT.

WHILE BOTH NAM AND GFS IN BETTER AGREEMENT WITH AMOUNT OF

INSTABILITY AND DEPTH OF MIXED LAYER...HOLDING AROUND 6K TO 7K FT

SATURDAY NIGHT INTO SUNDAY...THEY STILL DIFFER WITH RESPECT TO THE

PERSISTENCE OF ONSHORE FLOW. NAM 1000-850 MB WINDS REMAIN

NORTH-NORTHWEST ALONG THE SHORE...KEEPING BETTER CONVERGENCE JUST

OFFSHORE....WHILE GFS HAS MORE OF A NORTHEASTERLY DIRECTION THAT

KEEPS SNOW BAND ONSHORE FOR A PROLONGED PERIOD.

WILL AGAIN STAY WITH A BLEND THAT HOLDS SNOW CHANCES CLOSE TO THE

LAKESHORE...THEN ALL MODELS END LAKE-EFFECT AFTER 00Z MONDAY AS

CONVERGENCE MOVES OFFSHORE. COMBINATION OF SYNOPTIC SNOW AND

LAKE-EFFECT ACROSS LAKESHORE COUNTIES BRINGS EXPECTED SNOW TOTALS OF

1 TO 3 INCHES...WITH THE HIGHER TOTALS FROM MILWAUKEE SOUTH.

[weatherguru]

They use the NAM/GFS qpf maps for this?

[Chicago Storm]

FWIW...18z RGEM continues to favor SE. Wiconsin/NE. Illinois.

Looks good for Kenosha and Waukegan.

[Chicago Storm]

LOT...meh

TONIGHT...S/W TROF SHOULD PUSH THROUGH AREA AROUND MIDNIGHT AND

SHOULD SEE SNOW TAPER TO FLURRIES AFTERWARD. ATTENTION TURNS TO

LAKE EFFECT SNOW...WITH MAIN QUESTIONS BEING WHERE AND HOW MUCH.

ALREADY HAVE SEEN LAKE ENHANCED SHOWERS OFFSHORE THIS MORNING AND

AFTERNOON AND EXPECT THOSE TO RESURFACE AS SOON AS SYNOPTIC SYSTEM

MOVES TO THE EAST AFTER MIDNIGHT. NAM BUFR SOUNDINGS OVER SOUTHERN

LAKE MICHIGAN SUGGEST INVERSION HEIGHTS AROUND 4000 FT AND

LESS-THAN-FAVORABLE 850MB-SFC DELTA TS AROUND 10C. THESE VALUES BOTH

IMPROVE...BUT ONLY SLIGHTLY THOUGH SATURDAY MORNING. NORTHEASTERLY

FETCH WILL BRING SNOW SHOWERS INTO CENTRAL COOK COUNTY WHERE

ADDITIONAL LIGHT ACCUMULATIONS...IN THE 1 TO 3 INCH RANGE...THOUGH

NOT TOO CONFIDENT WITH THIS NUMBER AT THE MOMENT.

FOR CHRISTMAS EVENING THROUGH NEW YEARS EVE...

LAKE EFFECT SNOW WILL CONTINUE TO BE OUR PRIMARY WEATHER PRODUCER

INTO LATE SUNDAY NIGHT. AS MENTIONED ABOVE...MODEL FORECASTS OF

850MB-SFC DELTA T NEVER BECOME TOO IMPRESSIVE THROUGH THIS

PERIOD. WINDS ALSO DO NOT FAVOR SUSTAINED ACTIVITY IN ANY ONE

LOCATION...SO BANDS WILL LIKELY SWING BACK AND FORTH ACROSS THE

IL/IN LINE BEFORE A SURFACE RIDGE MOVES INTO THE AREA ON MONDAY

AND CUTS OFF THE FETCH. SOME AREAS ALONG THE INDIANA SHORE COULD

SEE A FEW INCHES OF LAKE EFFECT SNOW SOLELY DUE TO THE PROLONGED

PERIOD OF ACTIVITY...BUT SNOWFALL RATES SHOULD STAY BELOW HEADLINE

CRITERIA.

[A-L-E-K]

Lol no headlines, I knew that warning (lol) wasnt happening.

[ILSNOW]

Lol no headlines, I knew that warning (lol) wasnt happening.

So Milwaukee goes with 1-3 lakeside counties with more south of Milwaukee and KLOT goes with ZIP. Im going with Tony!!!!

[tuanis]

LOT...meh

TONIGHT...S/W TROF SHOULD PUSH THROUGH AREA AROUND MIDNIGHT AND

SHOULD SEE SNOW TAPER TO FLURRIES AFTERWARD. ATTENTION TURNS TO

LAKE EFFECT SNOW...WITH MAIN QUESTIONS BEING WHERE AND HOW MUCH.

ALREADY HAVE SEEN LAKE ENHANCED SHOWERS OFFSHORE THIS MORNING AND

AFTERNOON AND EXPECT THOSE TO RESURFACE AS SOON AS SYNOPTIC SYSTEM

MOVES TO THE EAST AFTER MIDNIGHT. NAM BUFR SOUNDINGS OVER SOUTHERN

LAKE MICHIGAN SUGGEST INVERSION HEIGHTS AROUND 4000 FT AND

LESS-THAN-FAVORABLE 850MB-SFC DELTA TS AROUND 10C. THESE VALUES BOTH

IMPROVE...BUT ONLY SLIGHTLY THOUGH SATURDAY MORNING. NORTHEASTERLY

FETCH WILL BRING SNOW SHOWERS INTO CENTRAL COOK COUNTY WHERE

ADDITIONAL LIGHT ACCUMULATIONS...IN THE 1 TO 3 INCH RANGE...THOUGH

NOT TOO CONFIDENT WITH THIS NUMBER AT THE MOMENT.

FOR CHRISTMAS EVENING THROUGH NEW YEARS EVE...

LAKE EFFECT SNOW WILL CONTINUE TO BE OUR PRIMARY WEATHER PRODUCER

INTO LATE SUNDAY NIGHT. AS MENTIONED ABOVE...MODEL FORECASTS OF

850MB-SFC DELTA T NEVER BECOME TOO IMPRESSIVE THROUGH THIS

PERIOD. WINDS ALSO DO NOT FAVOR SUSTAINED ACTIVITY IN ANY ONE

LOCATION...SO BANDS WILL LIKELY SWING BACK AND FORTH ACROSS THE

IL/IN LINE BEFORE A SURFACE RIDGE MOVES INTO THE AREA ON MONDAY

AND CUTS OFF THE FETCH. SOME AREAS ALONG THE INDIANA SHORE COULD

SEE A FEW INCHES OF LAKE EFFECT SNOW SOLELY DUE TO THE PROLONGED

PERIOD OF ACTIVITY...BUT SNOWFALL RATES SHOULD STAY BELOW HEADLINE

CRITERIA.

Seems pretty realistic, I don't think we'll see much more than 3"-5" total anywhere except in a very few localized areas. Never know though... it's hard to get a prolonged LE event this side of the lake.

[weatherguru]

So Milwaukee goes with 1-3 lakeside counties with more south of Milwaukee and KLOT goes with ZIP. Im going with Tony!!!!

LOT being conservative until the bands gets going.

[weatherguru]

Will have to watch radar trends tonight. I dont buy it yet.

[tuanis]

LOT being conservative until the bands gets going.

They do say this:

PERIODS OF LAKE EFFECT SNOW ARE EXPECTED TO DEVELOP TONIGHT AS

COLDER AIR SPREADS INTO THE REGION VIA NORTHEAST WINDS. THIS SNOW

WILL IMPACT NORTHEAST ILLINOIS COUNTIES NEAR LAKE MICHIGAN TONIGHT

INTO SATURDAY.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

THE POTENTIAL FOR SIGNIFICANT LAKE EFFECT SNOW WILL CONTINUE

SATURDAY AND SUNDAY. HOWEVER...CURRENT FORECAST GUIDANCE SUGGESTS

THAT THE WINDS WILL SHIFT OUT OF THE NORTH LATER IN THE DAY

SATURDAY INTO SATURDAY NIGHT. THIS WILL LIKELY SHIFT THE FOCUS OF

LAKE EFFECT SNOW INTO SOUTHEAST COOK COUNTY AND INTO NORTHWEST

INDIANA. SEVERAL INCHES OF ACCUMULATION ARE POSSIBLE ACROSS THE

CHICAGO AREA COUNTIES NEAR LAKE MICHIGAN SATURDAY INTO SATURDAY

EVENING...AND LOCALLY HEAVY ACCUMULATION IS POSSIBLE FOR NORTHWEST

INDIANA SATURDAY NIGHT INTO SUNDAY. ANOTHER PERIOD OF LAKE EFFECT

SNOW MAY BRING MORE LIGHT ACCUMULATIONS TO THE NEAR SHORE ILLINOIS

COUNTIES ON SUNDAY BEFORE THE THREAT ENDS ON MONDAY. CONTINUE TO

MONITOR THE LATEST FORECASTS FOR MORE DETAILED INFORMATION ON THIS

DEVELOPING LAKE EFFECT SNOW EVENT.

[weatherguru]

They do say this:

Yeah I know and GFS backed off and shuts it down earlier the 18z but not worried about that. LES should get in after 00z. They wont really know until the band gets going. My opion is sthey thinking scattered lake snow showers and that I can understand it wont add alot but if we see a more organized heavier band in NE IL then someone will get hammered.

[weatherguru]

//DISCUSSION...UPDATED 20Z...

BROAD AREA OF SN ACROSS THE ENTIRE REGION...WITH NUMEROUS ASOS

OBS ACROSS IA/WESTERN IL REPORTING 1/4SM TO 1/2SM. CIGS HAVE

HOVERED IN MOST LOCATIONS AT IFR CONDS FROM 800-1000FT AGL...WITH

A FEW LOCATIONS DIPPING TO 500FT AGL FOR A BRIEF PERIOD OF TIME.

WSR-88D KLOT HAS CONTINUED TO SHOW BEST REFLECTIVITY DRIFTING

SOUTH...WHICH SUGGESTS SOME IMPROVEMENT TO NORTHERN IL AIRFIELDS.

FEEL THIS IS A BIT OF A TEASE AS UPPER LEVEL LOW PRESSURE REMAINS

WEST OF THE AIRFIELDS. MODEL GUIDANCE HAS CONTINUE TO SUGGEST THAT

THIS UPPER LEVEL ENERGY WILL NOT ARRIVE ACROSS THE AREA UNTIL

LATER THIS EVE. ONCE THAT ARRIVES STEADIER SN COULD PUSH WEST TO

EAST ACROSS NORTHERN IL/NORTHWEST IN AIRFIELDS. IF THE TRACK IS

SLIGHTLY FURTHER SOUTH THEN AGAIN THE STEADIER SN WILL DRIFT SOUTH

AWAY FROM TERMINALS. AS PREVIOUSLY NOTED IT WILL BE A CLOSE CALL

AS TO WHEN AND PRECISELY WHERE THE IFR CIGS/VSBYS WILL BE AND FOR

HOW LONG. HAVE OPTED TO KEEP CIGS/VSBYS DOWN TO IFR

CONDS...ALTHOUGH WE MAY HAVE A FEW PERIODS WHERE WE BOUNCE TO

MVFR.

WINDS WILL CONTINUE TO VEER TO THE NE ABOUT 020-040 DEG...WITH

LAKE EFFECT SNOW DEVELOPING. THIS PRESENTS ANOTHER CHALLENGE FOR

AVIATION TRAFFIC AS THIS MAY ALLOW LAKE SN TO PUSH FURTHER INLAND

AND APPROACH ORD/MDW. BEST TIMING FOR THIS APPEARS TO BE AFT

00Z...WHICH HAS BEEN SIMILAR TO EARLIER THINKING OF TIMING. HAVE

CONTINUED TO HOLD VSBYS DOWN ARND 1SM FOR ORD/MDW/DPA/GYY...AND

COULD EASILY SEE GYY DROPPING FOR A PERIOD TO 1/4SM WITH A NARROW

BAND OF LAKE EFFECT SNOW OVERNIGHT. CIGS FOR RFD WILL START TO

IMPROVE ARND DAYBREAK SAT...GRADUALLY PUSHING TO MVFR CIGS BY

MIDDAY SAT. ELSEWHERE EXPECT CIGS TO LINGER ARND 1000-1500FT AGL

THRU MIDDAY SAT.

BEACHLER

//ORD AND MDW CONFIDENCE...UPDATED 22Z...

* LOW/MEDIUM CONFIDENCE ON IFR CIGS FORECAST.

* LOW CONFIDENCE ON IFR VSBYS WITH LGT/MOD SN.

* HIGH CONFIDENCE ON WIND DIR/SPEED FORECAST.

SHEA

//OUTLOOK FOR ORD/MDW FOR 06Z SUNDAY-12Z THURSDAY...UPDATED 18Z...

SATURDAY NIGHT...MVFR PATCHY IFR CIGS. LK EFF SN IN FAVORED AREAS.

SUNDAY...PSBL MVFR W/LK EFF SN.

MONDAY...PSBL MVFR W/LK EFF SN.

TUESDAY...VFR.

WEDNESDAY...VFR. PSBL MVFR W/SN.

THURSDAY...VFR. PSBL MVFR W/SN.

BEACHLER

&&

.MARINE...

132 PM CST

N TO NE WINDS WILL GRADUALLY INCREASE AS HI PRES EXTENDING FROM

HUDSON BAY SSW TO THE RIO GRADE DRIFTS ONLY VERY SLOWLY E THRU SAT

NIGHT. THE N TO NE WINDS WILL PERSIST UNTIL THE HI SETTLES OVER

THE UPPER GREAT LAKES AND THE MS VALLEY DURING MON. WINDS THEN

BACK TO OUT OF THE SW BY TUE MORNING AS THE RIDGE AXIS MOVES E

OVER THE SOUTHEASTERN U.S.

TRS

&&

.LOT WATCHES/WARNINGS/ADVISORIES...

IL...WINTER WEATHER ADVISORY...ILZ003-ILZ008-ILZ010-ILZ011-ILZ019-

ILZ021-ILZ023-ILZ032-ILZ033-ILZ039 UNTIL MIDNIGHT SATURDAY.

IN...WINTER WEATHER ADVISORY...INZ019 UNTIL MIDNIGHT SATURDAY.

LM...NONE.

&&

$$

[IWXwx]

Not a snow weenie here but I agree with his maps. Lately with a more favorable NE IL lake snow and long duration I think it's right on target. Just may not be the exact location but quite similar in the end.

You've posted more in the 4 days you've been a member about this one lake effect event than I've posted since American was born.

Seriously, I hope you Chicago guys get blasted with an historic lake event. These opportunities don't come along very often for that side of the Lake.

[Chicago Storm]

There is a weak meso low just east of the city.

[weatherguru]

There is a weak meso low just east of the city.

I sense LES will be kicking in or already has.

[A-L-E-K]

looks pretty 1 to 4 ish to me.

[Hoosier]

I gotta think a headline will be needed at some point. This stuff is tricky though.

[KeenerWx]

Going to reevaluate things between 10 and 12 tonight.

[KeenerWx]

There is a slight signal of lake enhancement currently..

Hopefully someone here gets a good Christmas present from L Michigan.

[michsnowfreak]

Hoosier, if you could, add SE MI (and maybe NW OH?) to the thread title. Looking very interesting here. What a nice Christmas this would be, start the day overcast with a 5" snowcover then see lake effect snow develop

BROAD CYCLONIC FLOW WILL CONTINUE TO DEVELOP ALOFT OVER THE GREAT

LAKES THROUGH THE REST OF THE HOLIDAY WEEKEND. THIS PROCESS WILL NOT

BRING MUCH SNOW OF ITS OWN BUT WILL ENHANCE THE ENVIRONMENT FOR LAKE

EFFECT SNOW SHOWERS IN SE MICHIGAN WITH THE HELP OF SMALLER SCALE

CIRCULATIONS. THESE FEATURES WILL GENERATE SURFACE REFLECTIONS THAT

WILL VEER THE LOW LEVEL WIND TO THE NORTHEAST OVER OUR AREA AND

SUPPORT INLAND PENETRATION OF SNOW SHOWERS FROM LAKE HURON. ADDED

TOGETHER FROM SATURDAY MORNING THROUGH SUNDAY NIGHT, THE ACTIVITY

WILL RESULT IN AN INCH OR TWO OF ACCUMULATION OVER MOST OF SE

MICHIGAN WITH THE POSSIBLE EXCEPTION OF LESSER AMOUNTS IN THE TRI

CITIES. ON THE OTHER HAND, PORTIONS OF THE THUMB COULD RECEIVE

ACCUMULATION OF 2 TO 4 INCHES DURING THE SAME TIME PERIOD, WITH THE

HIGHER END OF THAT RANGE MORE LIKELY NEAR THE LAKE HURON SHORELINE.

THERE IS GOOD CONFIDENCE IN THE MODEL HANDLING OF THE OVERALL LAKE

EFFECT/ENHANCED SCENARIO ON THE LARGE SCALE, BUT THE THERMODYNAMIC

DETAILS OF THE CONVECTIVE ENVIRONMENT OVER THE LAKE REMAIN MORE

UNCERTAIN. THE 12Z RUN OF THE NAM ILLUSTRATES THIS TODAY WITH ITS

DEPICTION OF LAKE EFFECT OVER THE SOUTH HALF OF LAKE HURON INTO

ONTARIO APPEARING OVERDONE JUDGING BY EXETER RADAR IMAGERY SHOWING

BARELY A RETURN AT PRESS TIME. SATELLITE IMAGERY AND MODEL ANALYSIS

FIELDS INDICATE DRY AIR IS CLEARLY A LIMITING FACTOR WITH A

NORTHWEST FETCH IN THE MIDST OF THE WEAK LAKE-INDUCED CONVERGENCE

FIELD. HOWEVER, THERE SHOULD BE AN INCREASE IN ACTIVITY AS THE LOW

LEVEL FLOW BACKS TOWARD THE NORTH TONIGHT AND THEN NORTHEAST

DURING SATURDAY WITH A LONGER FETCH OVER OPEN WATER CONTRIBUTING

TO MULTIPLE BAND FORMATION INTO THE THUMB. THE NAM GIVES US THE

BEST CHANCE TO GET THE WIND CORRECT AS THE UPPER LEVEL

CIRCULATIONS INTERACT WITH THE LAKE INDUCED SURFACE PRESSURE

FIELD, AND THUS BETTER IDENTIFY REGIONS OF MORE CONCENTRATED

ACTIVITY. FOR NOW, DECIDED TO USE ABOUT HALF THE NAM QPF OVER A

SLIGHTLY LARGER AREA TO THAT END AND TO ACCOUNT FOR THE ACTIVE

BIAS IN THE 12Z DATA BASED ON OBSERVATIONS THIS AFTERNOON. THIS

GETS US THROUGH SATURDAY WITH ABOUT AN INCH OF ACCUMULATION IN THE

THUMB COUNTIES AND LESS THAN AN INCH ALONG AND WEST OF THE

INTERSTATE 75 CORRIDOR.

THE PEAK OF THIS EVENT STILL LOOKS LIKE IT WILL OCCUR SATURDAY NIGHT

AND SUNDAY AS THE LAST SHORT WAVE UPPER CIRCULATION MOVES OVER THE

REGION. THIS WAVE WILL SOLIDIFY THE MOISTURE PROFILE OVER AND

UPSTREAM OF THE LAKE AND HELP LIFT CONVECTIVE DEPTH AS THE LOW LEVEL

THERMAL TROUGH INTENSIFIES. FORECAST SOUNDINGS DO SHOW THE

EQUILIBRIUM LEVEL ABOVE -10C DURING SATURDAY BUT EVEN MORESO

SATURDAY NIGHT AND SUNDAY REACHING UP TO ABOUT 7000 FEET/-12C AND

REMAINING THERE THROUGH SUNDAY WITH LAKE-850MB DELTA-T NEAR 18C.

THESE IMPROVED ELEMENTS WILL LIKELY LEAD TO MORE EFFICIENT

SNOWFALL AND A FARTHER INLAND REACH OF THE ACTIVITY. ANOTHER INCH

OR TWO OF ACCUMULATION LOOKS EASILY ATTAINABLE WITH LOCALLY HIGHER

AMOUNTS NEAR THE SHORELINE, DEPENDING ON THE STAYING POWER OF THE

NORTHEAST FLOW.

[Hoosier]

IWX

OTHER SHORT TERM CONCERN IS LAKE EFFECT POTENTIAL IN OUR EXTREME NORTHWEST CHRISTMAS DAY AND NIGHT. NORTHERLY LOW LEVEL FLOW EXPECTED TO DEVELOP OVERNIGHT IN WAKE OF MID LEVEL TROUGH PASSAGE. DELTA T VALUES INCREASE TO MID TEENS WITH RISING INVERSION HEIGHTS AND LOW LEVEL MOISTURE REMAINS IN PLACE. SHOULD SEE A DECENT SINGLE BAND SET UP OVER WESTERN HALF OF THE LAKE AND MAINLY AFFECT COUNTIES JUST WEST OF OUR AREA. HOWEVER...NORTHERLY CYCLONIC FLOW COUPLED WITH SECONDARY TROUGH PASSAGE MAY AID IN SECONDARY LAKE ENHANCED SNOW BANDS ACROSS BERRIEN AND LAPORTE COUNTIES WHERE TRAJECTORIES SUGGEST FLOW WILL STILL BE OFF A SIGNIFICANT PORTION OF THE LAKE. NAM12 AND LOCAL WRF SHOWING SOME DECENT 925MB OMEGA IN THIS AREA. WILL GO WITH SCATTERED SNOW SHOWER WORDING HERE WITH SOME MINOR ACCUMULATIONS. HOWEVER...SIGNIFICANT BAND WILL BE JUST WEST OF THIS AREA AS PROGGED BY MOST MESOSCALE MODELS. ANY EASTWARD SHIFT COULD BRING THIS BAND BACK INTO OUR AREA AND THUS WILL BE MONITORED CLOSELY.

[KeenerWx]

IWX

OTHER SHORT TERM CONCERN IS LAKE EFFECT POTENTIAL IN OUR EXTREME NORTHWEST CHRISTMAS DAY AND NIGHT. NORTHERLY LOW LEVEL FLOW EXPECTED TO DEVELOP OVERNIGHT IN WAKE OF MID LEVEL TROUGH PASSAGE. DELTA T VALUES INCREASE TO MID TEENS WITH RISING INVERSION HEIGHTS AND LOW LEVEL MOISTURE REMAINS IN PLACE. SHOULD SEE A DECENT SINGLE BAND SET UP OVER WESTERN HALF OF THE LAKE AND MAINLY AFFECT COUNTIES JUST WEST OF OUR AREA. HOWEVER...NORTHERLY CYCLONIC FLOW COUPLED WITH SECONDARY TROUGH PASSAGE MAY AID IN SECONDARY LAKE ENHANCED SNOW BANDS ACROSS BERRIEN AND LAPORTE COUNTIES WHERE TRAJECTORIES SUGGEST FLOW WILL STILL BE OFF A SIGNIFICANT PORTION OF THE LAKE. NAM12 AND LOCAL WRF SHOWING SOME DECENT 925MB OMEGA IN THIS AREA. WILL GO WITH SCATTERED SNOW SHOWER WORDING HERE WITH SOME MINOR ACCUMULATIONS. HOWEVER...SIGNIFICANT BAND WILL BE JUST WEST OF THIS AREA AS PROGGED BY MOST MESOSCALE MODELS. ANY EASTWARD SHIFT COULD BRING THIS BAND BACK INTO OUR AREA AND THUS WILL BE MONITORED CLOSELY.

IWX wants Chicago's Christmas present..

Just kidding.

[Hoosier]

INCLUDING THE CITIES OF...WAUKEGAN...CHICAGO

651 PM CST FRI DEC 24 2010

NOW

RADAR IS BEGINNING TO INDICATE DISORGANIZED AREAS OF LAKE ENHANCED SNOWFALL MAKING ITS WAY ONSHORE ACROSS PORTIONS OF LAKE AND COOK COUNTIES. WHILE HEAVIER PLUMES OF SNOWFALL HAVE YET TO FORM...THESE AREAS COULD SEE OCCASIONAL MODERATE BURSTS OF SNOW. CONTINUE TO EXPECT UP TO AN INCH OF ADDITIONAL SNOW THROUGH MIDNIGHT TONIGHT...THOUGH SOME AREAS MAY SEE SLIGHTLY HIGHER AMOUNTS.